2009 IAA Planetary Defense Conference: Day 4 (Session 6)

2009 IAA Planetary Defense Conference: Day 4 (Session 6)

Session 6 What's Happening Now
Session Chairs: Richard Tremayne-Smith, Ray Williamson

- Asteroid Threats: A Call for Global Response: The ASE's Challenge to the International Community
Schweickart, R. ; Jones, T.D. ; Prunariu, D.D. (Association of Space Explorers, United States)

Started in 2005, discovery of 2004 MN4, 1 in 27 probability of impact in 2029, Indian Tsunami, India/Pakistan earthquake, took on the responsibility of brining international geopolitical issue to the threat, formed a committee (Rusty-chairman) – fall of 2005, next three and half years, brought geopolitical community, this is decision program, this is an international issue – may not preclude unilateral action, recognize that the decision program – may be the biggest of three fundamental thing, report currently in deliberation within the COPUOS, read last paragraph of executive summary, five nations within the ASE, various additional members for the Panel on Asteroid Threat, no one represented a national government, people from 11 nations in Panel on Asteroid Threat, four international workshops were held over two years, same panel for all meetings, Sept. 2007 (Romania), April 2008 (Costa Rica) – assisted by F.-Chang Diaz, September 2008 (San Francisco) – Ed Lu, completed report and presented to Richard Crowter (succeeded Richard Tremayne-Smith) on Action Team 14, briefings on the report given to the following: COSPAR, IAC/IAF, Inter-Academy Council/Panel, COPUOS (06, 07,08, 09), permanent representatives (June 2009 COPUOS meeting), permanent UN groups, space faring nations, CSA/ISRO/ESA/NASA, Pres. Costa Rica, Pres. Of General Assembly, key recommendations, did not presume judgment the judgment of nations states, (IAWN, information analysis warning network) – 80% of the people in this room dealing with, put this as a network since existing structures – must come together in a coordinated network, MPOG (Mission Planning and Operations Group) – space faring nations, on top of this is a MAOG (mission authorization group) – oversight of activity (needs to represent the international community), IAWN – must inform when non-deflection (coordinated information channel to terrestrial mitigation), 2008 TC3 brought awareness of near real-time challenge, status of report: it is too early on the outcome of this process, recommendations are precedent setting, for the establishing of a standing international decision making process, work we have done has put this squarely on the nation states (http://www.space-explores.org/ATACGR.pdf)

- NEO Report by the IAA
Ivan Bekey (United States)

Will be out in two week, just been issues by IAA – not the intent to do new science/analysis – but do put together information from previous workshops and build on other workshops, cover the breadth of the problem – aimed at policy/decision makers in this area, IAA is premier expert/non-governmental science and technology organization, long time in coming (all by email), 9 chapters in the report,
http://iaaweb.org/iaa/Scientific%20Activity/Study%20Groups/SG%20Commission%203/sg35/sg35finalreport.pdf, in the spectrum of hazards, mitigating the impact of NEOs is very important in the context of all serious hazards of concern to humanity, technology for in-space mission is fragile for detection/impact/warning, look at fast techniques and slow techniques, goes into the nuclear issue, ends by finding that typically, chapters on mitigation and physiological and sociological factors, principal recommendations on detection: expand JPL Horizons/U. Pisa NEODyd NEO computation centers, expand spacegaurd, LSST, space telescopes, augment Minor Planet Center, ground radars, for policy: create an analogue of the Interagency Space Debris Coordination Committee,

- US–NAS/NRC Study Progress
Michael F. A’Hearn (United States)

The academy panel has not started writing the report, for year I was the astronomer with the mediated gaze then turned to becoming a little boy throwing things in a sand box, Deep Impact: selected for science not mitigation (deflection – order of magnitude only: delta V – 0.1 micron/sec, semi-major axis – about 20 m, orbital period = 0.01 seconds, immeasurably small change in orbit (1 km), 1998 fund and in 1999 got new money, 2008 NASA assumed all funding for MPC, international contributions to survey/discovery negligible thus far (NEOSSAT, launch 2010), many individuals self-organizing scientists, Asteroid Finder/SSB – funded by DLR through Phase B (both focused on IEOs – inner Earth objects, the use of English in this community is strange, additional international activity (NEODys, astrometric follow-up, characterization) – this is not the type of international collaboration, 2006 – detailed study by NASA (never put in a budget request), 2008 congress told NASA to fund an NRC study and review previous study (may mean Congress is ready to put money in here), NRC study under NASA Contract, Steering Comm. With two panels (Survey/Detection Panel) / Mitigation Panel, charge to comm.: how should we best approach to discovering 90% of NEOs > 140 m by 2020, optional approach to developing a deflection strategy and international collaboration? Some issues; PanStarrs has only USAF funding (earmark for const.) – no operating budget for survey expect for NASA at 30% for three years pof PS1, LSST – only private, WIDE funded – not a full catalog, cataloging or early warning, space component (mid-IR), completion and cost, what subsets will be missed, how long, mitigate threat today or one 10 years from now, long or short warning times, how small a risk should be mitigated, should we focus on next impactor or one with the biggest threat, for this meeting – how do we make international collaboration – how? A lot of coordination with characterization – self organizing not coordinated, mitigation requires international collaboration, still in the data collection phase, GAIA should also be included for IEOs

- NEOimpactor - A Tool for Assessing Earth's Vulnerability to the NEO Impact Hazard
Bailey, N.J.1; Swinerd, G.G.2; Lewis, H.G.2; Crowther, R.3
1School of Engineering Sciences (United Kingdom); 2School of Engineering, University Southampton (United Kingdom); 3Rutherford Appleton Laboratory (United Kingdom)

NEOImpactor is combined land and ocean NEO impact tool, models NEOs from point of atmospheric entry, IGE is modeled, interdisciplinary research atmospheric + land + ocean), WARD model – ocean, Collins model – land, small asteroid population from 25-250 m radius, existing models largely ignore human consequences, output is focused on who and what is at risk, difficulty in consequence modeling, single impact investigations, compare two locations, multiple impact studies individual consequences are hard to validate, relative impact consequences can ne mad e(64x32 cell grid adopted 2048 impact simulations – 2.1 days), each impact is 1.5 minutes, maps generated use grid system, what do the results tell us: people in Southeast Asia are most affected, infrastructure in North America and Europe is most as risk – obvious. Small objects are significant on the land, large objects become more significant when impacts the ocean, country data can be extracted, Casualty Rank top: China, Damage rank: US, combined Ranking (China, US, India, Japan, Brazil) – the countries with the most to lose, what make a country vulnerable coastline, topology, population distributions, infrastructure concentrations). Not analyzing probability of objects hitting, simulation using random impact locations, (impacting into the center of cells), ability to simulate along paths, can do other natural disasters (fire, flood, hurricane, etc.), transition radius (around 35 m radius) – below radius ocean impact is lessened – on land impact is more important, warning against fragmentation, R.S.: come a long way from conference – strong plea to state things in NEO diameter and not radius, Oslo: ocean impact near field effects, continental shelf impacts, atmospheric effects may be important, Clark Chapman: presentation style is organized, important to include uncertainties somehow you can incorporate to capture uncertainty including in response

- The NEO Primer: A Tool For Collaboration, Communication, and Outreach
Weeden, B.; Williamson, R. (Secure World Foundation, United States)

Air Force officer – focused on space activities in ICBM operations, in 1943 collection of 5 essays by Robert Seber summed up knowledge of nuclear fission (become entry level reading for all new scientists to the Manhattan project), the topic of NEOs and mitigation is not easy one and requires some level of understanding (Physics, Geology, orb. Mechanics, international law, psychology/sociology, international), community is growing, growth continues , many people from different disciplines, need a Los Alamos primer for NEOs (Collaboration, Communication, Outreach), initial focus on established disciplines in the NEO field (celestial mechanics and astrodynamics, etc.), what a wiki is? What goes over times overlooked is discussion, people can actually have a discussion about contents of page, traditional copyright has automatic reservation of all republication, limits “rip, mix, mash, burn”, new type of licensing called Creative Commons (copy left approach) – author can choose licenses, expand a primer into a full-fledged NEO wiki, have a separate wiki controlled by this community – contain public research data, would allow for global collaboration and allow for the public collaboration, allows more people to collaborate, primers could be used, SWF will volunteer to make this a reality, to organize a committee to identify volunteer experts, SWF will host the wiki until a suitable home can be found, development stages (NEO primer, and then build upon this).

Panel Discussion:

D. M.: Value of report?

R.S.: ASE report on the work agenda of UN, specific high level outcome, congressional mandate of NRC study,

I.B.: Making report 7 years ago from the IAA (took so long to do the report) – value was jus tin putting out a comprehensive report,

P.G.: making models into GIS, update Wikipedia, what would you like to see in 2 years,

R.S.: ASE success will be continued discussion, interesting to see degree of avoidance of international community

- 2nd Planetary Defense Conference (Bucharest, Romania) 9-14 May 2011

- J.M. Contant
IAA
New series of meetings and conferences, made a formal request to host the conference, formal call distributed widely, received two formal proposals (several informal): Cameroon and Romania were two entries, Romania active

- Dumitru-Dorin Prunariu
Romanian Space Agency (RSA), Head
Space agency taking undertaking of new international meetings, first IAA conference last September, Romania space agency head (head of UN COPUOS), 7th largest European country, 22 M people, EU/NATO member, 1509-1579 Conrad Hass, lived and worked in Sibiu (predecessor 3 stage rocket), Spiru Haret (n-body problem), Hermann Oberth (born in Sibiu), Romanian Space Agency (RSA) established in 1991, main organizers of UNISPACE III in 1999, 15ht ASE meeting in 1999, 1st Romanian and NASA agreement, elected for Chairmen for 2010-2011, 2006 signed cooperation with ESA, every two years science and space exhibitions, 2007 ASE Workshop, multiple meetings, House of Parliament (9-14 May 2011) in Romania, could be until May 13 given number of papers

- Session 7 Panel Session & Discussion - Findings & Recommendations

W. Ailor( Moderator): AIAA is a sponsor but not a primary sponsor, 2004: 13 page white paper, developed over 2 months, White paper as basis for AIAA position paper, AIAA paper: Create a US org for PD?, expands Spaceguard survey (at that time did not phone number, now L. Johnson at NASA HQ), 2007 white paper:, 12 page document over 2 months, Recommendations in five areas, 2009 white paper as IAA position paper

Panel Discussion:

- Review of All Previous Panels and Overall Discussion of White Paper

- Review of Session 1: Discovery, Tracking, Characterization

R.S.: Emphasize the international aspects even more than what we see in the room, potential equivalent to LSST becoming ISS-like, international ownership of LSST – bold recommendation – would you include Arecibo as part of that? Should the world own security assets,

S. Chesley: not part of LSST management, involved with some science, LSST is not a fundamentally a NEO search project (first is dark matter/energy, solar systems) – internationalizing it is one of the directions (27 institutional members – 2 from outside US) – this is any avenue

R.S: is that not international collaboration and not ownership (NSF and DoE are funders)

B.A.: is there a way to being international funding?

Harris: LSST are entrepreneurs and probably have

Another audience member: characterization is lacking being, useful to try and improve current capability to carry out fundamental observation about size and composition
LSST: no proprietary data

D. Morrison: talk as if the next generation survey is a done deal, those and current surveys are not done yet, clearly needs to do funding support,

Review of Session 2: Mission and Campaign Design

Ian: Pursue studies since mission concepts, learned a lot and one of the examples – response to the Apophis Mission design competition – 40 proposals of excellent quality – done in this years put some good result in industry, Hayabusa experience, science community should have a stronger link to the engineering community, NEOMAP panel experience – reflect on this experience, ask ourselves – how we can extend this experience – build a true user community and make this link to the science community (different models and engineering community), Orion CEV – curious to see – component inspirational component also proved that it is next steps to tackle before more extensive – new scenario for this community, two mission concepts – Foresight and Proba-IP – low cost – reduce as cheap as possible and technology demonstration – number of technologies to be proved in specific scenarios based upon different bodies,

Audience member: Need practical testing of deflection methods – done in a scenario as close as possible to a real deflection mission, need experience

R.S.: resurction of D. Q. mission: observer and impactor (relatively minor capital) – convert that s/c to gravity tractor capability (single program demonstrate impact and prevision trimming mission) – a specific embodiment in a single mission, slight modification (NEOMAP chairman – Alan Harris – the younger),

B.A.: how do we increase the likelihood that is will happen,

I.C.: accumulated a key lessons learned, a lot or work in the U.S., wonder if talk about an international cooperation, if a small first strip to do a small joint study, nice to talk about international cooperation – already see big challenges behind those terms, start fostering international cooperation – not real engineers – could be established in a practical term

I.C.: ITAR – NEOMAP meeting, Pete Worden present – put out idea line to avoid ITAR problem potential U.S. handling interceptor and ESA continuing with the orbiter, wondering if we get tha specific, cooperative program without confronting ITAR directly

P.G.: getting funding from other agencies is larger,

A.H. (younger): it seems as if ESA has run out of mandate, run out of mandate, member countries really need this, how we could try and focus a little pressure on Europenan governments that this is needed (D.Q. as example)

B.A.: get this out as AIAA position paper, NASA/ESA study on going to the outer planet (Europa/Ganyanmede) missions (experience),

D. Morrison: international aspects that the only nation that has sent to a S/C to a sub kilometer, lots of rendezvous spacecraft that do not involve difficult interfaces,

A. Galvez: just a bit of distinction – some cooperation in some programs – different in others, cannot put everything in the same place- cooperation in the same place – Laplace maybe not an example – something we will have to make an effort to explain,

SSA guy: science program is following cosmic vision (collaboration mission) – asteroid deflection mission part of that – Marco Polo mission (no way to get asteroid deflection mission), one is technology demonstration, orbiter around an asteroid – ESA should use a technology demonstration capability – already there in some way with Proba-IP, only other option is make it part of SSA where in the next phase is in-space and you perhaps could build s/c – idea was initially observatory – perhaps take small part of make a deflection mission, not the science program

DLR guy: reluctant to split mission perhaps in ESA – hit the same target twice
I.C.: splitting D.Q. has never been a problem – key elements of mission concept, clearly splitable to allow international cooperation, ITAR not just about also about component- sometimes not independent – low level working experience

B.A.: design a campaign, important factor for decision makers, what is reliability mean to an overall mission concept, may have multiple countries, different techniques (what does that mean)

P. Michel: overlap with what was said, NEOMAP – never had a problem with splitting the mission, realistic with limited budget, GT + D.Q. would be good, modeling is also important, low level simulation work – benchmarking, even if we make a precursor mission, one other way is to use a deflection mission for numerical codes once they are validated by a mission

L. Johnson: who own D.Q. proposal?

A. Galvez: D.Q.: internal assessment, used as an input in the technical directorate who are managing Proba, two mission that are flown in LEO, next project will be much more significant, need cooperation, Proba-IP is one of the candidates, has not been considered?

L. Johnson: who has the details for the D.Q. proposal so somebody could see what is could take to add GT capability – study report which includes NEOMAP report (freely available) three Phase A studies – owned by ESA, that is what it will take to understand what would be needed to added to the missions (someone will have to go in and figure out what will added to it) – recommendation of including that

Michel: make this mission, find a target- not obvious, object small enough for a gravity tractor

B.A.: send email to comments,

- Review of Session 4: Impacts and Consequences

D. Morrison: who would have thought we would have had two impacts (Peru and 2008 TC3)l what we have done we have moved more and more into the small object of the spectrum (no longer talking about large objects) – surveys are retiring risk, so much of this session with smaller objects, A. Harris and caveats (just brightness) – each of those steps has uncertainty, M. Boslough – fascinating simulations – main scientific message, noticed in some sense, keyhole – providing new information, new updated information, rewrite textbook on airburst object, do these things provide recommendations, substantial amount of those recommendations, still primarily in science learning more about NEOs and small ones, do not see an international efforts, not mind revisit most of previous recommendations

R.S.: opportunity to say something new – NASA has responsibility for space science – NASA has no responsibility for public safety, need political natural hazard that has public safety

A. Harris: elephant in the corner is not retired, do not forget entirely in large bodies, tsunami is big question on long way – raising the questions.

- Review of Session 5: Policy, Preparedness, Deciding to Act

A. Galvez: no international dimension to carry out an international scenario analysis, what kind of framework would be appropriate, critical diameter issue might allow decision makers to make better local and regional damage potential

M. Boslough: short term approach to TC3: standardize mechanism for 2008 TC3 (could be considered a threat) – establish a protocol for warning, perhaps for aircraft/people, help establish credibility and international cooperation,

Review of Session 6: What's Happening Now

R. Williamson: Secure World Foundation willing to provide website and so forth for, ASE and IAA study and look forward to the national research council study (represent progress) – may want to think about something up to date and perhaps a wiki or some other mechanism that can be accessed by a wide variety of individuals, refining NEO impactor study – tools that should be developed for the future,

Additional comments:

A. Harris (the younger): three conditions on retiring the risk – new generation survey should be done – second consideration that they find nothing too severe and then monitor the orbits,

R.S.: deal for Dave Morrison – commit to you that I say NEO if you get away from the retired the risk, we have retired the surprise is a better phrase, two years from now – dedicated session with the international risk management structures of the world (communication link with them) for the next conference, have a session by then to inform us of their work, do not refer to war games

B.A.: scenario that they ran, would a group like us posing a scenario that would a credible scenario

Andy: support a Wikipedia would have been good, how the major press companies are informed, preemptive strike on press companies on these companies – go straight to them – notification to the public,

Audience member: Include consideration to other space assets?

B.A.: an impact could throw debris up to satellite orbits

Texas guy: clear that audience started from scientists, going to need a primer to get them up to speed for non-establishment audience

R. T. Smith: some parts of the community being involved, Have been asked by on PD community: "Where is your association of victims?" Teneriffa conference, later report published last year on disasters management,

P. Gatterson: also difficult to imagine a scenario (backups) engaging the spacefaring nations military and nuclear arms, a realistic deflection scenario would have them and expose them

B.A.: post that as a scenario (Apophis impact in scenario)

D. Dearborn: bringing in safety organization (DHS), should also have people who talk to them between them, DoS people, would be the ones communicating

C. Chapman: Teneriffa conference: why don’t you come to our meetings? We have to do outreach and go to their meetings, huge community

A. Galvez: attract interest to show we can provide tools, modeling and simulation (may give credibility), international nature of surveys

B. Ailor; world experts on topic, need to increase awareness, main thing that is lacking is money to do studies and research, suggest go home and tell them about encourage them to support PD

2009 IAA Planetary Defense Conference: Day 3 (Sessions 4 and 5)

2009 IAA Planetary Defense Conference: Day 3 (Session 4)

Keynote
Impacts, Catastrophism and Technological Capability to Other Areas of Endeavor
Oliver Morton (Chief News and Features Editor, Nature, London, UK)

Been to previous planetary defense conferences (in 2004), “Ways to see the world, ways to save the world: NEO awareness and mitigation in context”

Look at things in a broader context, “encounters with asteroids alter perspectives” Skhizein – Jeremy Clapin – about a man who gets hits by a meteorite – ends up standing 72cm to the right of the real world, goes to the psychologist (10 minutes long), illustrates the main them, tend to think in blockbuster terms – useful to think about a small scale – this Endeavour is also quirky and small scale – absolutely fascinating, all scientists talk about problem, you have had an extremely successful three decade success story – increased scientific understanding – the process may not have not been best sure, acceptance of K-T event, image from Nature of various experts, much to do – need more money, need a better policy framework, look at the broader shifts in people’s perceptions, elements of success: the “astronomer’s gaze” - sees farther and more than anyone else and the way they see if more divorced from touching than is any other form of vision (general way of science sees the universe) – there is second scientific realm that astronomer has privileged access to (fundamentally other) – meditated by telescopes, Hubble deep field – total perspective that disaggregates perceptive – Irish telescope (telescope) – made during the Irish famine, colleague’s book “Captured by Aliens” (book) – whole chapter of the Eagle nebula – the majesty began to fade – does the mean exist only because we insert it into the frame, what does it mean? “Comets not longer frighten the public – this is a results which science certainly has the right to congratulate itself, “astronomers should leave to astrologers the task of seeking the cause of earthly events in the star (NYTimes), overturning the astronomer’s gaze, reintroduction of the catastrophe, “100 Suns/ Full Moon” images, Lucifer’s hammer – thriller by Larry Niven and Jerry Pournelle – obvious to naturalize nuclear war – this is not limited to nuclear war – to some extent it says that civilization has already ended (fear of Charles Manson) – sense of something has gone wrong – disturbing power – brings together anxieties, Matthew Paris – the sublime – being in the presence of the dangerous – what is think about massive destruction – Indian Ocean tsunami – “relished” those numbers – auctioneer of calamity, also its humorous aspects, “Dead Like Me” – first episode – hit by falling lavatory seat from a disused Russian space station, next topic: planetary perspective: the world we experience is objectively a planet, other planet got his regularly – drove debate about earth, way of seeing mediated by spacecraft, quote from Rusty about the planetary perspective, place within a context, element of success (“long zoom” – Steve Johnson) – most periods have ways of seeing (MTV cuts, renaissance, etc.), this period have long zoom (fractals, Google Earth, social movements, difficult way of thinking) – brains did not evolve to understand the scale – Powers of Ten, the mediation is the computer – could think the computer is alienating, images from his presentation came from “Contact” when talking about the long zoom – when you pull al the way is a person’s eye – provides a continuity, once you expand your notion to include a cell phone, 2008 TC3 is the long zoom – astronomer’s gaze to truly personal, the way the world thinks about this, what we do makes it seem much more normal – scientific and cultural normalization, “you don’t have to try as hard” these days as much – “relax” – you are broadly doing what you want – a humped has been crossed, normalization into planning, sense of continuity (Hayabusa at Itokawa to Orion CEV at asteroid), twitter feed (low flying rocks) – when an asteroid passes by the earth’s orbit – thousands of people get that by mobile phone, hard to remember live in a science fictional world, normalization into research (MRO image of mid-latitude of Mars, few impact craters formed since MRO when into orbit, imager can use impacts in near real time for science, white stuff is ice), people looking at planets, the case for Mars impacts – the best use of asteroid deflection is to allow access to and sampling on substance, allow unusual access but astrobiotoically extremely relevant conditions, allow experiment with precision guidance of asteroid, prediction: there will be a deliberate impacts on Mars before there is a deflection away from Mars, Lessons for elsewhere – NEOS and their mitigation provide something like a toy model for other issues of governance, in particular there are lessons here for people trying to protect fht world from photons as well as from rocks,

Similarities between impact mitigation and geoengineering (massive potential risk, good public arguments, fringe issue, tainted with science fiction, resistance from mainstream, resistance from civil society, accidents, dramatic natural demonstration – SL9 / Mt. Pinatubo – both are examples – Spaceguard report in 1990s / NRC report) – big advantage – not part of a large serious policy debate – episodes of intense media coverage pumped by real world events, focus on small scale detection work of semi scientific type, slightly retiring risk, low level by real level political support, lobbying with specific claims, technological piggybacking, integration into normal science, changes to conceptual framework (tsunamis, keyholes, gravity tugs), the asteroid impact mitigation community has been the scene of significant arguments and disagreement, some established norms, changed its mind about things, the same time it has made process, moving between scales all seem more real, “clumsy” solutions – it is quite something to learn from the sublime – great achievement,

Session 4 Neo Impacts & Consequences
Session Chairs: David Morrison, Al Harris

Announcement of poster papers

Two posters associated with this session

- Trigo-Rodriguez (“The Impact of NEOs and their fragments recorded from the ground…”), Spanish fireball network, trakcing bright fireballs, 2002NY40 case (discovered in 2006 by network), trajectory and orbital information about daylight bodies, in 2006 obtained ninth orbit of a meteorite in the solar system Villalbto fall), Puetro Lapice (May 10 2007) – bolide object, 30cm sized meteoroid, Bejar superbolide (11-7-2008), brightest event in network, more than 1 meter in diameter entering, disruption of C/1919Q2 Metcalf comet (ended at height of 22 km altitude),

- Ferrier, et al (“Atmospheric entry of Apophis: A preliminary study”) atmospheric has a general protective effect on Apophis entry, Apophis could face heavy fragmentation (for slope around 20 degrees) leading to smaller fragment significantly slower and lighter than the initial object, ablation will deeply influence the final mass of Apophis fragments (final total mass from 0.01% to 40% of the total mass), for skimming (and rarest angles) Apophis could skip and eventually leave the atmosphere

- Alan Harris comment: many times we have been caught in general cases, sometimes many small things could do ground damage, need to address dispersion outcome of entry speeds (100m object may not get to ground, few meters across object could get to the ground)

- The Nature of Airbursts and their Contribution to the Impact Threat
Mark Boslough (Sandia National Laboratory, United States)
First part describe airbursts, in the past when we model airburst we made oversimplifications, still simplifying but making fewer simplifying assumptions, more complicated phenomena, have not done a complete quantitative analysis – greater then we thought, relative threat from LAA (Low Altitude Airbursts) is increasing, most of the integrated threat is from the large objects, 100 m / 100 Mt has 1/100 chance in century (100-100-100 event, every 10K years) – will dominate threat once 90% of object larger than 140 m, the next destructive NEO is virtually certain (greater than 99% chance), to be LAA, IPP on Climate Change defining verbally descriptive terms, less than 200 m in diameter dominated by air burst, tech development similar to threat reduction time, other reasons to deflect and fragment small asteroids (for resources and possibility for GEO engineering), put one of these in L1 point and dust (could reduce number of photons), mitigation should focus on small ones (~100 meters ) – could just be civil defense, Al Harris iconic plot – plot of the long zoom, LAAs are not explosions (unlike bombs – point source), generate upward ballistic plumes (saw in 1994 from SL9), generate downward vortex rings (smoke rings that carry a lot of energy), enhance heat transport to surface – even as KE is lost – momentum still continues - unlike bomb, carries mechanical energy downward, anisotropic radiation patterns, two types of LAA, Tunguska type – fireball descends rapidly but does not reach the ground – expands – enough surface - shockwave to surface, area to start losing energy, 1-10Mt (1908), Libyan Desert Glass (29 M years ago), fireball is much larger and descends all the way to the surface, threshold yield is about 10 Mt, its own inertia tends to expand on ground – trees would vaporize, was at 100th anniversary, no evidence of glass in Tunguska, most of the Tunguska damage is mechanical, slope angle of 35% (like Tunguska), treefall at 50 m/s, threshold is less if terrain is not flat and trees not healthy (5 mt explosions at 12 km abouve surface at 35 degrees angle), for type 2, consequences, get stationary wind at bottom at epicenter (fireball), cannot make this not happen for 15 MT explosion, Pancake model (Chyba, et al, in 1993) – revisited – vortex at surface (2-d potential effect, maybe at 3d would break up), previous Tunguska yield estimates were too high, moemetum coupling to atmosphere t, solid, earthm and tsunami amy be higher, ,Type 2 airbusrst could generate fireablls in co=nat with surface over hundred of square kilomtters fo tens of seconds (possibility ti ifind more evidence in the geological record).

K.H.: association with velocity, M.B.: 15km/s, if you had time and computational time then you could examine multiple parameter space

- Every Threatening Asteroid an Apophis
Lu, E.T. (B612 Foundation, United States)

Presented by Rusty in place of Ed, fundamental point that Ed wanted to put across – Apophis at keyhole, every deflection will involve an Apophis case, primary deflection = miss the Earth, as soon as move it away from the Earth, all along the LOV are keyhole for future impacts, total impulse for Apophis (beta = 2-10), because of uncertainty then many potential keyhole, after primary deflection, next step after primary is to determine if there is secondary deflection, shepherding = guiding between keyholes, targeting JPL/N612 GT targeting, where do you want to move it? Not going to show that there is preference but…there is an Earth in there, either you take it off to either side of the Earth – geopolitical of which direction you go in terms of movement – that issue may determine which way you go or determined by cheapest way if it is near one edge..perhaps you look at where you want to come back, the question you have to ask If you we are going to take the responsibility then where do we want to put it and why – the philosophy and criteria of targeting – begin thinking about, what you can do is run a sequence – develop a long term plan for any asteroid – not just a one time thing but what do you want to do with it – a long term plan that includes that pumps up through a series of gravitational pulses, pumping up aphelion after 80 year (5 deflections) and end up with aphelion out to hill radius , convert it to a non NEO, or use gravitational force of Mars of Venus, the concept here is primary deflection and a capability to trim (this is Rusty’s point), Ed’s point: 60-65% of cases over time have future approaches, means it is important to measure after deflection,

- The Carancas Event: a Recent Hypervelocity Impact Crater in the Altiplano
Tancredi, G.1; Ishitsuka, J.2; Schultz, P.3; Harris, S.3; Brown, P.4; ReVelle, D.51Fac. Ciencias (Montevideo); 2Instituto Geofísico del Peru (Montevideo); 3Dept. Geological Sciences, Brown University (United States); 4Dept. of Physics and Astronomy, University of Western Ontario (Canada); 5Meteorological Modeling Team, Los Alamos National Laboratory (United States)

List of distribution of attendees to PDC 2009, need more diversity perhaps, Lindley Johnson stated “that a 2-5 m meteoroid would oinly create a fireball” – this event challenges the view, close to many borders (Chile/Bolivia/Peru), the witnesses (people said that cloud of dust, and animals), photo of smoke trail, crater – diameter of 14m, almost immediately filled with underground water, Sept. 15, 2007 11:45 LT fireball was observed, explosion was observed, several pieces of material was collected, several people claimed to be sick, many seismic stations that were able to detect event, first seismic detection of an extraterrestrial impact on Earth (47 km away), estimate of orbit from data, carancas meteorites, ordinary chondrite type H4/5 (stony), hit on dry riverbed, 13.5 m crater, depth of 2.5 m, meteorite fragments in soil, quartz grains with shock metamorphism due to impact, impact velocity was >3km.s and possibly on the order of 3 – 6 km/s (based upon petrology studies and pressures on samples), size of less than one meter in size, 1-3 tons of TNT impact energy, shed that was knocked by material, 100 m away a man was turned down (but no ear drum effects), bull has one horn that is turned down because bull fell down, why is this so relevant> a fresh impact, impact crater, impact at high altitude, ordinary chondrite, seismic data, material from ground, usual picture is that a 1 ton stony meteorite producing a 14 m crater is not possible according to previous studies, initial mass was 7-12 tons, 1-6-2 m (initial velocity, 12-17 km/s, impact was 3-6km/s), seismic efficiency: 10^-3, heath problems were exaggerated, about 8 2 m meteorites per year, paper to appear in ACM issue in MAPS, rejected from nature, very few samples of the meteorite – many taken by local people,

Dearborn: said that look at the approach angle, shallow approach angle have a longer time – less ablation, angle was order of 50-60 degrees

- Near-Field Effects of Asteroid Impacts in Deep Water
Gisler, G.1; Weaver, R.2 1University of Oslo (Norway); 2Los Alamos National Laboratory (United States)

Only a few impact craters under 5km of water, all undersea craters are on the continental shelf, as asteroid has to be very big to make a crater on the seafloor, only get up to 1km diameter to get effect, tsunami deposits might be sign of deep water impacts, debate within the community about finding these (community does not fully accept this evidence), do deep water impacts make tsunamis at all, started in 2002 testing out new computer at Los Alamos, collapse of that jet that makes the tsunami wave, transient crates made usually probably asymmetrically, evolution after that is relatively symmetric, wave that is generated is surprisingly ineffective, the wave breaks in mid-ocean (high amplitude, regular tsunami has a low amplitude – propagates as shallow wave) – 1 km wave that breaks in mid-ocean – does not propagate very well, the newest simulations therefore study mostly near field effects and sediment transport, done with code called Sage (written by SAIC adopted by Los Alamos), 1000 m impact into 5km of water, 1 km sediment, basalt crust, did various trades of various diameters, resultant wave is only factor of 2 larger than transient crater, 1km (477 m at 30 km, 17 m at 2000 km), 100 m (37m at 30km, 1.3 m at 2000 km), less than 10 m for those asteroid less than 500 m, asteroid tsunamis do not resemble classical tsunamis, landslide case – extremely regular particles, asteroid impact: more chaotic interaction – more possible for energy to escape, could wish we could use another term for asteroid impact tsunamis, more of the asteroid’s kinetic energy goes into vaporizing water – then a lot less energy for tsunami, near field effects extend to tens of km away from impact site, smaller impacts are in fact comparable to sever topical storms, NOAA : a hurricane dissipates on order to 0.7 GT per day (Katrina storm surge was around 8m), 500 m dividing line, deflect asteroid greater than 500m if landing in the middle of the ocean, less smaller ones fall into the sea, if near a populated coastline, Mark and Gisler will attempt to do an airburst combined analysis, if in open sea, monitor wave and use for checking the code (“mad scientist”)

Question: depends on depth of water, shallow water issue, shallow water case interesting – the only case known that tsunami from impact is KT impact, slumps from the shaking caused tsunami, need to run shallow water cases

Question: Most of calculations are 2-D, a 3-D calculation would able to run largest computer (calc. would take a week).

- Insurance and Meteors Fall: Proposal of a Methodology for Estimating the Risk and Modeling
Consequences for the Insurance Sector in France
Garbolino, E.1; Michel, P.2; Holsapple, K.3 1Ecole des Mines de Paris (France); 2National Center for Scientific Research (France); 3University of Washington (United States)

Geographer from France, a year ago insurance company told to assess portfolio to meteor impact, meteor falls are usually considered as too improbable, need to answer the cost of damage and the vulnerability of insurance portfolio, damage assessment is a key activity, interdisciplinary approach, (technical, stakes, and cost). Territorial vulnerability (sensibility) = function (intensity, probability of occurrence, sensitivity of the stakes, intrinsic resilience, resilience to return to prior state, spatial decision support system, case study of French Rivera (Nice, 350 k inhabitants), tourist infrastructures, many ERP (establishment serving public), 4 scenarios (1m 10, 30, 50 m asteroid), airblast destroys building (small end is pushing model – clearly improvement, simple analogy taking nuclear airblast without, S 1 (6 k people, $426 M total cost) 30-50 m asteroid would destroy Nice (350 k people, $30B Euro), possible that insurance companies would be interested in covering this type of event, SDSS could be taken for emergency services,

D. ML: we do a danger talking about 6 meter objects, we create a bad false impression of risk,

C. Chapman: approach is valid approach, but the closer link between the this analysis and the actual effects of NEOs, this simple data is too simple misrepresents, get that link correct

Rusty: feel free what insurance company name – la Maif – national insurance company,
Clark Chapman: terminology, too late for NEO (should say N + E + O), meteor strikes – term,

J. Michel: demonstration of approach this

Perhaps look at equivalent events such as those that have been mentioned


- Estimating the NEO Population and Impact Risk: Past, Present and Future
Al Harris; Space Science Institute (United States)

Revised impact Kill Curve (airbursts and small land impacts, impact generated tsunami), short term warning – death plunge, probably only one out there in several km in diameter, largest size range – residual risk resides in fractional probability that one such body has not been found (not counting comets), seen that these things come in different speeds (smaller objects or larger objects going slower may delivery more energy to ground than average) – deal with dispersion of characteristics, revised kill curve published initially in 1993 – claim is that we have underestimated airburst (previous enhancements were nuclear airburst which are explosions with no momentum), Hills and Goda damage was 30 MT for Tunguska (too high), Mark suggestion as low as 3 MT (Alan Harris thinking 7.5 MT), revised kill curve, 4 times less massive body same as previous estimate, Revised kill curve for tsunami (adopted what Steve Ward/Chesley/Harris estimated run up, in report for 2002/2003 at the end of the calculation assumed that even thought only 10% of fatalities would die / the number of people affected could be used as property damage (value of Net Worth of Human, $1M/person, actual infrastructure is a factor of 10 down from cost/person), argue that tsunami damage is perhaps overdone – should based upon lives lost, elephant in the corner are the large ones (revisions make little difference for the large objects), 0.1-1km revised curve lower fatalities per year, less change to worry about in the small area, small things for surveys to find that remaining action, surveying for asteroids is like fishing (get what you get, the impact hazard in perceptive: when we get to next generation surveys (comets started getting to larger portion of threat), we have discovered half the objects the size of Apophis (next generation survey will generate Apophis – but not as many as feared), not going to be worried about Apophis, the survey is 84% complete to 1km, 95% complete to 2km, only a small fraction of Tunguska size NEAs have been found, next generation durvey should find 25% of objects that pose ground impact, short term warning – TC3 event – 20% chance to look at right part of sky, 10% chance of catching Tc3 event with current survey (found one after decade of survey is not surprising), in principle LSST may see things on a monthly basis (but no follow-up), worried about impact hazard – the next generation survey will find anything that make to the ground – LSST will pick things pick more than one month in advance (the nest you can do is 35% since you are not watching the other part)

Global impact events: 1 km was selected as lower limit where you could believe you have global effects, 1 km object = largest volcanic event (similar)

D. M: goal is 90% of 140, but that includes more as well

- Casualty and Fatality Rates of Massive Extinction After Asteroid Impact with Earth
Ortega, G.1; Bavandi, A.1; Weikert, S.2; Giron Sierra, J.M.3; Laurel, C.4 1ESA (Netherlands); 2ASTOS Solutions GmbH (Germany); 3University of Madrid (Spain); 4Periapsis Visual Software (United States)

Job is compute optimal trajectories at ESA, earth catastrophic event more than 10,000 people killed at same time, Maximum Probable Loss (MPL): greatest financial amount of loss from previously defined event, used ATOS tool (included DARS – debris analysis re-rentry spacecraft), also included DIA (debris impact analysis) and RAM (risk analysis) , parametric analysis of various asteroid sizes, formula for impact, various simulations of various cities, risk of impact is larges than 1 in a million risk of death use in ESA terms

Panel Sessions:

M. Boslough: One of the ways that Tunguska was overestimated, momentum would carry fireball all the way to the surface if using older numbers, look at the intensity of the shock wave from a nuclear explosion you get more danage then you see at Tunguska, concluded that it may be a smaller energy (3-5 MT may be 1 in 1000 year event) but also less frequency (larger events where getting to be implausible)

A. Harris: 300-500 year event for Tunguska, the population has dropped by a factor of 2-3 and energy has also dropped

A Harris (the younger): One phenomena about electromagnetic pulse and whether we would expect that and waht sort of size?

M. Boslough: observationally there was an E-mag pulse effects for Tunguska and SL9 impacts , you will get a plume (1000 km high for Tunguska) - different process for EM pulse, small scale events have caused transmission lines to fail, ionization effects can be part of the hazard - something that we would not want to ignore

Dearborn: scaling nuclear by yield for EMP, can see EMP in conventional explosives, have looked at EMP increase for conventional explosive, trying to get someone in his lab to look at it (for other reasons)

K.H.: want to focus on Hill and Goga approach...most of the energy goes into ground, Hills and Goga may overestimate using nuclear blast data for ground effects

A. Harris: Jack Hills fan of tsunamis - made the assumption that even a 100 m object (crate damage), curves at top may be not correct,

D. Morrison: blast wave for large object may not be that important

J. Michel: point out that everyone is making models, rate of numbers for phenomena, resolution for modeling is higher than what can be done, what are the things that are uncertain

A. Harris: Mark B. did a poster at AGU (from disaster movies), had in the last few year (asteroids actually hitting something, Peru and Sudan) - we do not see disaster movies, forget the world is very empty place, highly unlikely

M. Boslough: started with disclaimer - qualitative outputs are what are important, done the next level of analysis, point source - now point source with momentum, does not include viscosity / only 2-D, a good fluid dynamics simulation, how to calibrate: airbursts happen more often

Oliver: catastrophic interpretation of cities, chances of hitting cities are small, ways to have maps for blast area of Tunguska (compared to cities), guard against,

A. Harris: Chance of Tunguska hitting your town about the same as you drowning in toilet

R. S.: Political decision makers will mis-perceive and worst case will be the perception of impact

Gisler: calibrate codes with smaller events and tsunamis in the past, "perhaps of computing is insight and numbers" look at smaller events, Van Doren effect – based on results of underwater nuclear tests, these waves are similar to impact tsunami waves, small asteroid impacts in water (are dangerous on a local basis), if something were to provide 2004 tsunami event (that is still far short of global catastrophe),

A Harris: looked at various different historical report, the integral of all reports multiplied by credibility is greater than one, cars/mailboxes, by all odds someone should have been killed in the last century

Audience member: Source says 190 from (John Lewis book) last century killed

Tancredi: Terrestrial material on the side indicated that impact parameters

2009 IAA Planetary Defense Conference: Day 3 (Session 5)

Session 5 Policy, Preparedness, Deciding to Act
Session Chairs: Andres Galvez, A.C. Charania

- Report on University of Nebraska-Lincoln Conference "Near-Earth Objects: Risks, Responses and Opportunities–Legal Aspects"
Frans von der Dunk (University of Nebraska-Lincoln, United States)

"ASE NEO Committee report: Asteroid Threats: A Call for Global Response," report came to three conclusions: there is a capacity to detect / a capacity to act / missing of international decision making structure, risks not distributed in propositional to capabilities (Sudan and Peru not space fairing nations), risks not proportional to costs, who is going to pay, these are places where the law comes in, report delivered in Sept. 2008 briefing of key UN players and major states, Action Team 14 within the UN structure, what is the role of the legal subcommittee of COPUOS?, have three groups and UN Sec. council has three “groups” underneath (specific groups of functions), US Sec. Council to mandate whatever happens in a specific concept of deflection, UNL conference: setting the scene / legal/political aspects / international legal aspects and exploring NEOs and domestic US laws of NEO, and intergovernmental panel on Legal and Policy Aspects of NEO response activities (every continent representative), role of the military in various scenarios, liability (for not reporting, for not deflecting, for not being successfully, past incident with NOAA lawsuit about Indian Ocean tsunami information being withheld), what is asteroid is coming to N. Korea and US does nothing about it, liability convention (current legal regime), should we establish cross-waiver (like the ISS IGA- but that is between parties), good Samaritan, second major legal issue is international humanitarian responsibilities (obligation of provision of relevant information) - perhaps an institutional framework (builds trust) – parameters for action before actual case arises, obligation of protection of fundamental human rights, property issues (with a view to private involvement, current legal regime is unclear, ownership of minerals versus entire body, pressing need to make sure international and legal aspects do not get lost, need to further analyze legal issues, website: spaceandteleconlaw.unl.edu.conference./neopowerpoints

M. Boslough: telescope on asteroid – does it matter if you land the asteroid about who owns it?

von der Dunk: How about owning the mineralogical rights: IP: that exists in outer space, the problem arrive in moment when you extend the ownership to the mineral, one exception with risk to mankind – if you get information on might hit the risk to Earth you should share, composition for commercial purposes should be protected

- NEO Mitigation and Coordination with the Disaster Management Community
Chapman, C.; Schweickart, R. (B612 Foundation, United States)

Doubt if something were to happen there would be a broad based knowledge within the U.S. or globally would know how they would respond, need to respond between astronomers and others is more urgent, address the power law (small ones happen much more often that big events) – crucial thing for a practical perspective – smallest predictive impacts that might be dangerous (Skylab – re-entry was worldwide news), past PDCs have examined far larger NEOs than most likely, for every Apophis more than 50 Tunguskas, what is the smallest NEO that is dangerous – vital issue (if it is too small they will not care, metallic objects are dangerous but rare), SDT report in 2003 thought 50 m, Boslough suggest 30-40m, should we be unconcerned about 25 m object, Al Harris chart is not diameter but have an H value (uncertainty a nominal 25 m body may be 50 m in diameter), short term warning – the new reality, better than 1 chance in 3 that the Spaceguard will provide short term warning (few weeks) during the current decade, TC3 teaches us that we have an early warning system – rethink communication channels, 2008 TC3 : 4 m asteroid (an annual impact on Earth) – astronomers have overlooked short term Spaceguard survey, current survey will find 35% of NEAs > 30m on final plunge, will find more on final plunge than one long in advance, public officials must make decisions much more often than NEOs will actually hit, case of marginal impact scenarios, virtual impactor search (JPL impact page shows low probability impacts – cannot be observed before final plunge) – search for these virtual impactors weeks prior to impact – if coming from the Sun, radar would be required, we have risk corridors, some semi-serious is impact predictions that require analysis leading to no action, short term impact warning, mentioned short term warning , look at ASE recommendations

- Near-Earth Objects within the European Space Situational Awareness Programme
Koschny, D.1; Bobrinsky, N.2; del Monte, L.3
1ESA/ESTEC (Netherlands); 2ESA/ESOC (Germany); 3ESA/HQ (France)

Objective of SSA programme declaring: environment, threats, and the sustainable exploitation of outer space (three segments: space debris, space weather, NEOs, later: imaging), most of the effort is in space debris, in Nov. 2008 – preparatory phase started, last for 10 years after this phase, what does it consist of: network of sensors (ground and space-based), data centers, common data policy, optical programme, not a science driven needs, science needed to do program, do not have to justify by scientific nature, shall issue impact warnings, customers and users (replace decision makers with government, insurance companies want to make sure it is low risk, a customer as one who pays), NEO Data centre (not one place – distributed amongst many countries in ESA), status: write a customer requirements document – will be written in the next few weeks, start creating a European network of sensors (Intelsat will pay for orbital debris information), set up prototype service until 2009, just finished ESA external document,

- Results of Multi-Agency Deflection and Disaster Exercise
Garretson, P.1; Johnson, L.2
1Council on Foreign Relations (United States); 2NASA/HQ (United States)

New report is a summary of events, a simulation was performed of a short term days) and long term (years) impact scenario with members fro various US government military and civilian agencies, a new report is out that outlines results, it is not an official position of the USG or any of the agencies involved, it would help into insight into real decision making, has done previous work with the USAF Future Concepts office (including backcasting analysis), why event held? Look at high catastrophe events with high consequence, a letter from NASA HQ was secured to help obtain momentum for event, most people in simulation, “if not us, who? Would do such a simulation game, initially participants may have thought this would have a sci-fi nature to the event, 27 people plus 3 offsite participated in the event, multiple agencies- maybe OSTP in the future, most agency role players felt the responsibility for planetary defense against PHO was someone else’s responsibility, attendees were mostly action officers from their various organizations, looking for the richest (but perhaps not most probable scenario), called 2008 Innoculatus, Lindley J./Mark B./Mark ) in room, went for the broadest swath of people, two groups looking at different threats (same people, consecutive scenarios), first threat was 72 hours from impact (lost 10 hours getting ready in simulation), 50 m metallic body headed for D.C. area, 270 m rubble pile hitting the Nigerian Coast, missing some key people (namely state and local planner), one of the issues is that the error ellipse for impact is so broad – emergency response it is difficult to optimize, scenarios basically made 2029 today, future planning scenarios may be less ambitious, insights: NEO plans not captured in existing plans, NASA does have some sort of a contingency process – other agencies do not, need for more senior players potentially (not too senior), most people did not laugh or giggle – there was a feeling that “I need to need to tell the boss about this,” very complex – overlapping nature of problem, need for documentation, no consensus achieved on responsibility – argued it was “the other guy” – some consensus that ground response was DHS perhaps, some felt the response would be similar to a Manhattan project with all resources ay disposal, software tools deficit to support decision make and communicate information, need for a federated systems – end estate would be a turn-key model that accepts the best data, turnkey mission planning and modeling, significant effects not captured, public may be aware before senior decision makers, limited time for evacuation decision before best information will be available, architecture for short warning time, public safety requires federal government, preferred approach for short notice scenario was stand-off nuclear (for the 7 year scenario felt there was a need for maturation, not for future scenario planners – some players though tools/simulations were distracting, next time include all agencies, media/press could be useful, NSC added, use higher level representations

- The Need to Match Action with Legislation: Some Inconsistencies in the OST
Azcarraga Arana, A.1; Gonzalez Ferreiro, E.2
1Sener Ingeniería Y Sistemas (Spain); 2Cede (Centro Español De Derecho Espacial) (Spain)

How to bring together experts in all areas (science/engineering + policy): financial crisis + climatic change, if you are able to detect something in diameter, everything has been in the military – nothing is wrong with that, example of Russian anti-submarine cruiser for Black sea (since aircraft carriers are forbidden), solve problem and not give artificial names, need for global international coordination, Galileo example is not a good example, new international body – as soon as one member asks for action – take action, look at the OST and start changing it immediately, afraid next COPUOS meeting not a clear sense of urgency there, need more media papers, change the word NEO, use PHO, don’t let things go to manana,

Panel Discussion:

2009 IAA Planetary Defense Conference: Day 2 (Sessions 2 and 3)

2009 IAA Planetary Defense Conference: Day 2 (Session 2)

Session 2 Mission and Campaign Design
Session Chairs: Mariella Graziano, Ian Carnelli, Andreas Rathke

- R. Tremayne-Smith
Discussion of orbital debris problem, vide of U.S. recent AST-like event / Iridium impact, conception of LEO not the same as before, not about mitigation, checking for debris done casually, in low earth orbits need to have propulsion/maneuver, A-Train set of satellites has to move through this region, even more disciplines, getting more difficult to get space open for business, going to need same mechanisms for the orbit area,

Announcement of poster papers
- MAAT: NASA Ames research study, ESPA ring variant of NASA ARC Common bus, secondary payload, 10 month long launch opportunity, 3.1 km/s Delta-V (includes margin), ability to vary launch site, 2014 science mission for 6 months, modified LCROSS instrument suite
- Optimal control of gravity tractor spacecraft near arbitrarily shaped asteroids (M. Gehler, et al), see the influence of arbitrary gravity field on control forces, how GT could be optimally controlled, Discrete Mechanics and Optimal Control applicable to hovering control for very close to asteroids, solar sail size should be matched to asteroids, used 1 asteroid radius (about 500 meters),
- PANIC – mission concept study for mini autonomous lander (NASA Ames summer study), a micro scale lander (three instruments), total mass (9kg for 48 hours, $25M)
- Evolutionary optimization in a conceptual design of a NEA mission, what is netter of a single impacts or multiple kinetic impactor
- Small Solar System Body mitigation (J.T. Grundman), a realist approach, when down the list, and looked at all the problems

- Didymos Explorer and PANIC: Asteroid Concept Studies of the S4P Program at NASA Ames
Rozitis, B.1; Bellerose, J.2; Cook, A.3; Fahnestock, E.4; Mester, C.5; Murdoch, N.6; Olds, P.7; Reddy, V.8; Schindler, K.9; Thomas, C.10; Yamaguchi, T.11; Asphaug, E.12 ; Marchis, F.13 1The Open University (United Kingdom); 2JAXA/JSPEC (Japan); 3Rensselaer Polytechnic Institute (United States); 4University of Michigan (United States); 5Stanford University (United States); 6ESTEC/ESA (Netherlands); 7UARC/NASA Ames (United States); 8University of North Dakota (United States); 9University of Dresden (Germany); 10Massachusetts Institute of Technology (United States); 11The Graduate University for Advanced Studies (Japan); 12University of California (United States); 13SETI (United States)

Develop 1-2 concept studies for small spacecraft, integrate small spacecraft exploration, train the next generation of scientists/project leaders, 11 students from various backgrounds, no NEA binary and no M type asteroid has been visited yet, decided on Didymos (1996 GT), a Mars crossing Amor binary, also a PHO, low delta V, 750 m diameter (primary), accomplish the first in-situ investigation of binary asteroid, science objectives: asteroid geology, shapes and gravity fields, Yarkovsky effect, Yorp effect (if enough force then potential to make a secondary object), asteroid composition (link asteroid and meteorite classes), six instruments, use of Delta II vehicle (launch on 12 Nov. 2014), mission duration of 2 years, flybys at 5km and 3km, perform close approach, minimize eclipse time so hovering becomes a better approach and allow for secure deployment for lander, 151.8 kg (dry) /. 307.9 kg, cost ($136.5 M with 30% contingency), 207.6 W, Didymos explorer mission will allow thorough study, Q/A

- Foresight: Designing a Radio Transponder Mission to Near Earth Asteroid Apophis
Charania, A.1; Olds, J.1; Koenig, J.2 1 SaceWorks Engineering, Inc. (SEI) (United States); 2SpaceDev, Inc. (United States)

- The Challenge of Navigating Toward and Around a Small, Irregular NEO
Gil-Fernandez, J.; Prieto-Llanos, T.; Cadenas, R.; Corral, C.; Graziano, M. (GMV, Spain)

Examined multiple types of missions, impact missions and rendezvous missions, proximity operations, need high accuracy for navigation (around one meter), new sensors, requirements for NEO missions are highly demanding for GNC, robust GNC system, result shows impactor only could potentially do mission without specific shape model (not relying on shape information)

- PROBA-IP: An ESA Technology Demonstration Mission Targeted to Apophis
Cano, J.L.1; Peñín, L.F.1; Cornara, S.1; Santandrea, S.2; Marcos, F.3; López, A.3; Jentsch, C.4; Bernhardsdotter, E.5; Taylor, M.6; Page, O.7; 1DEIMOS Space S.L. (Spain); 2ESA / ESTEC (Netherlands); 3EADS CASA Espacio (Spain); 4EADS Astrium Satellites (Germany); 5SSC (Sweden); 6SSTL (United Kingdom); 7SciSys (United

Follow-on to Don Quixote orbiter (Sancho), consortium performing for ESA, related to in-orbit demonstration of autonomous technologies, PROBA-2 (Sept. 2009 launch): solar observatory, PROBA for formation flying, PROBA-IP take technologies to interplanetary field, need to determine a cost specific mission, scientific goals only if margins will allow for it, current study is a preliminary concept evaluation, launch before 2015,choose asteroids close to the Earth, count on cheap launchers, use of low thrust propulsion, reuse an upper stage design (use of LISA Pathfinder’s propulsive stage being developed for ESA already), initial filter sin asteroids resulted in 60 asteroid (Apophis was promising and choose as primary) – choose 1989 UQ selected as a back-up launch in 2017, VEGA launcher, need for active control during to high unstable dynamic orbit, analysis of a Phto-Gravitationally Stable Orbit, consideration of different types of SEP engines, arriving with low velocity, departing in Jan 2015, 1.892 km/s departure velocity, arrival date in in 2017, 435 kg wet mass / 350 kg dry mass, delta-V of 3.9 km/s, GNC technologies (autonomous GN&C in cruise/approach/operations, use of DTU’s advanced stellar compass used as DTR/NAVCAM/WAC), power (two wing arrays, HEMP 3050 engine, easy to control – control mass flow rate – good for autonomous control), ACS (three axis stabilize, X-band, in middle of the study, study ends in summer, provide ESA with design concept at that point, potential for accurate determination of Apophis orbit and features, orbiter acting as beacon for deflection techniques

- Exploration of Near-Earth Objects via the Orion Crew Exploration Vehicle: A Planetary Defence Rationale
Abell, P.A.1; Korsmeyer, D.J.2; Landis, R.R.3; Jones, T.D.4; Adamo, D.5; Morrison, D.6; Lemke, L.6; Gonzales, A.6; Gershman, B.7; Sweetser, T.7; Johnson, L.8 1NASA Johnson Space Center / Planetary Science Institute (United States); 2Intelligent Systems Division, NASA Ames Research Center (United States); 3Mission Operations Directorate, NASA Johnson Space Center (United States); 4Association of Space Explorers (United States); 5Trajectory Consultant (United States); 6NASA Ames Research Center (United States); 7Jet Propulsion Laboratory (United States); 8NASA Headquarters (United States)

Paul Abell, feasibility study within Constellation program office at JSC, led out of Ames Research Center, Rob Landis/Ed Lu, a few folks at JPL (for trajectory analysis), Tom Jones, Bret Drake – sponser, this is only a Phase I feasibility study, NASA has not endorsed this yet, work done to date based on 4.5 month effort, a phase 2 study is as yet to be determined, proposed since 1966 (Eugene Smith) – “A Manned Flyby Mission to Eros”, no changes to Constellation element performance, established 4 misison concepts (2 bookends) based upon planned Cx launch system, at mid term considered mid-volume concepts (Ares V concepts), determine mission length options, Lower bookend (EELV for Centaur upper stage) + Ares I, Upper bookend (ARES V for EDS + LSAM) + Ares I, mid-volumes (use Ares V concept for Orion launch), for mid-volume (EDS and Orion SM perform rendezvous for 7-14 day visit with 20-75 outbound segment, which NEOs are a good target of opportunity with Earth-like orbits with low eccentricity and inclination, used JPL HORIZONS database, analyzed 90-120-150-180 day options, 9 NEOS founds within 2020-2035, 1999 AO10 is one potential target (2025/2206 mission) – 11.2 km/s reentry speed, value of human exploration to NEOs (exploration, science, and general public), expand human capability beyond low Earth orbit, asses resource potential for NEOs, gain operational experience for complex tasks (human/robots), assess psychology of crew autonomy at 10-20 second round trip for deep space, help indentify most efficient deep space exploration architectures, sample return, perform unprecedented deep-space voyage experience, would be a stepping stone type mission, demonstrate the way to Mars, understanding NEOs helpful for future impact threat, Can ye do this (Yes we can do it, Constellation program elements can support crew of 2-3), need to leverage next generation survey to find more targets, in depth Phase 2 mission analysis (applicable innovative technologies, radiation shielding, etc,), question: need to balance cost and missions (we have not done any cost estimate, not going to be a science mission/exploration mission/) – many communities, high cost – similar in cost to a lunar sortie (not the same as space station) – not the same as lunar outpost, question – chances to continue the study and do the mission- a lot of interest at NASA HQ, liked to do Phase 2 – interest at HQ leads to believe that Phase 2 will happen, holding pattern because of not permanent administrator

- Navigation and Guidance of Hayabusa around the Tiny Asteroid Itokawa
Yoshikawa, M.1; Kawaguchi, J.1; Hashimoto, T.1; Kubota, T.1; Terui, F.1; Ogawa, N.1; Ikeda, H.1; Kominato, T.2; Matsuoka, M.2; Uo, M.3 1JAXA (Japan); 2NEC Aerospace System (Japan); 3NEC Toshiba Space System (Japan)

Hayabusa changed the concept of small NEOs, before we thought many craters on Itokawa – surface covered with boulders, the study for Hayabusa is also important for spaceguard,June 2010 Earth reentry, have a brief history, first gravity swingby with low thrust propulsion, ground based operation was limited during Hayabausa touchdown (delay of 32 minutes and low bit rate of 8 kbps), intelligent GN&C is required, discussion of touchdown marker, during first touchdown maneuver - an obstacle was encountered and then went into feeefall near asteroid (unexpected), believe during the first touchdown may have captured some pieces of asteroid, mass estimation based upon using R&RR and LIDAR data, bulk density of 1.0 g/cm^3, Itokawa may be a rubble pile object, movie : "Hayabusa - Back to Earth" , next mission would like to know information inside the small bodies

- A Dawn-based Gravity Tractor and Kinetic Impactor Mission Concept Study
Wie, B. (Iowa State University, United States); Lam, Q. (Orbital Sciences Corporation, United States)

Changed name: NEO Deflection Systems Design, Dawn-based gravity tractor, multiple gravity tractor option also examined, NEO Deflection alternatives, three options (nuclear standoff or surface, kinetic impactor, gravity tractor, basic system (TII + Upper stage + 1400 kg payload – Dawn 900 kg GT or 1400 kg kinetic impactor or 900 kg interceptor with 500 kg nuclear explosive device), option 1 (Delta IV Heavy + Upper stage of Star + 6000 kg – multiple GT) , Option 2 (Ares V + Upper stage + 55 MT payload), Dawn spacecraft not designed for GT mission, use existing S/C bus technology, Dawn system to be presented at IAC 2009, two launch windows for Dawn based GT (2020 and 2021) for Apophis, delta-V from GTO is 3.45 km/s, Delta-IV heavy concept (three GTs/impactors/interceptors), GT mass = 2823 kg (wet mass, 1233 dry mass) for each GT, reason for multiple gravity tractor due to single point failure – more GTs allow for larger delta-V and more robust and reliable, do not need active station-keeping with multiple GTs – need more launch vehicles for such a system, paper in Journal of Guidance/Nav. Control, examined advanced low thrust propulsion, also a crewed 180 day NEO mission to Apophis – departure 10 September 2028, 160 days to Apophis – thought Ares I and Ares V is not enough (having trouble using design) – one page summary of ongoing project to be done during the summer, another poster paper on examining nuclear standoff for NEO deflection – estimation of optimal standoff of about 200 m (not 20 m as usual value) for a 1 km “solid” NEO, if GN&C control system has to meet 20 m optional standoff distance (this is too difficult for GN&C system) – we have to make decision (standoff explosion during fast flyby or rendezvous), position accuracy than 50cm (3 sigma), collaborative research with GMV aerospace for NEO terminal guidance, need large scaled funded R&D program for developing, testing, and deploying)

2009 IAA Planetary Defense Conference: Day 2 (Session 3)
Session 3 Deflection Technologies & Simulations
Session Chairs: Dario Izzo, Patrick Michel

Selected Posters:
Gary Johnson (Texas State Technical College), “An Electrostatic Variation of the Gravity Tractor “, Add an equipment kit to charge up the asteroid ans use the force of the electrostatic attraction (electrostatics as upgrade), “it smells good”, encourages community to take idea and run with it
Sanchez, J.P (Univ. og Glasgow): Consequences of fragmentation due to a NEO mitigation strategy
Pete Swan (from the space elevator community), NEO community, space elevator will be here for launch in 20-30 years, where do you park a space elevators, elevated parking structure for planetary defense pre-positioned assets
Adriano Campo Bagatin , “Response to collisions by NEA with gravitational aggregate internal structures”, study of collision outcomes depends on target’s number of components, the detailed internal structure of the impact region seems at least as important as the overall internal structure (texture) of the target

Antoni Perz-Poch, “Multi-spacecraft Electrostatic Tractor with Swarm Optimization”, real time coordination among satellites with an 4-6 satellites each 10 kV
Andrew Bacon, A Method for Fragmentation for Apophis, low cost fragmentation by using two or more Fregat Soyuz as smart impactors at resonant seismic frequency of Apophis to create an even distribution

- Methods for the Deflection of Threatening Asteroids: Some Problems, Theoretical
Considerations and a Few Myths
Keith Holsapple (University of Washington, U.S.)

Overview of some of the proposed methods for deflection, what do we need to do? After the astronomers say what we do, deflect (around 1-3 cm/s 10 years prior), disrupt or disperse it, or destroy it, a myth (destroy it): to vaporize a small 100 m asteroid requires about 30 Mtons of energy, you only change state, myth (“deflection is not possible in space”), danger of breaking it up is overestimated, delta momentum for deltaV for 1cm/s is 10^7 for H (momentum), table of mass for 100 m object: solid rocket (130 tons), gasoline (90 tons), dry cow dung (80 tons), bipropellant liquid rocket (70 tons), 10 km/s impactor (30 tons), 50 km/s impactor (6 tons), Fusion nuclear bomb (0.1 tons), E/C = c^2 ( 0.7 kg), things less than 30 tons could be considered, disrupt and dispersing it: needs 10^2 J/kg of asteroid, at or just under the surface, nuclear bomb (buried, surface, standoff), impacts unlikely to do except for smallest bodies), another myth: destruction energy might worsen the situation, there are neverl several large pieces in an impact disruption, typical fragment disruption velocities are several m/s, escape velocities are cm/s, tnes of cm/s are enough to miss the earth on the scale of a year, disruption would not be a problem if a year out or more, blowing it up at the last minute may work, how (bombs, bullets, gravity tractor), not good ideas (attached, surface landing, Yarkovsky, e-mag forces, tether), ones to focus on (nuclear, solar, laser), nukes are the last resort, is a method works better simply crashing its mass into the asteroid compared to its design method, forget it..unless there is a compelling reason, gravity tractor (10-100 factor just to impact), GT requires large mass/long time, no good ideas with interaction with surface for laser ablation (need to know dynamics), nice picture (MADMEN) – real surface tie it down, some methods have political problems (nukes in space, moving something slowly over the course of the earth –liability/weapon), composition problems (impacts, nukes, mass drivers, lasers, solar), porous materials are very good at absorbing energy shock, the forces on any stake in a rubble pile scale linearly with gravity (10^-5 to 10^-6 probability) – fastening with biggest item may not work, controllability/precision, robust mission with multiple instantaneous times, further analysis of nuclear (for porous material need to move into 20 m close), bullets (beta factor – due to blow back, do not know how much), B=1 (perfectly plastic impactor), other value it becomes a cratering problem, porous materials very little of beta (experiments would be good), with a single impact (200 m), multiple impact could do a km, an approach along the trajectory is not required, can hit it off center, no going to disrupt it, traj accuracy (mass, shape, spin, thermal inertia), kinetic impactor (just need mass) – thus Don Quixote would be preferred mission.

- Asteroid Deflection by Means of Electromagnetic Forces During an Earth Fly-by
Sanjurjo-Rivo, M.; Peláez, J. (Universidad Politécnica de Madrid, Spain)
Few works devoted to the analysis of deflection maneuver during Earth flyby (magnetic field and enhancement of gravitational interactions), uses a patched conic approximation (objective: avoid keyhole), electrostatic interaction (charge asteroid, electrodynamic tether (rigid attached to the asteroid)l – not feasible, can use these forces in indirect way, e-d tether modify the shape, electrodynamic tether, tether length of 350m E-d effect will be greater than the gravitational one, developed some techniques for electrostatic and E-D tethers

- Simulations of the Deflection of an Apophis-like Object
Jutzi, M.1; Michel, P.2; Benz, W.1 1University of Bern (Switzerland); 2University of Nice-Sophia Antipolis, Côte d'Azur Observatory (France)

Assumptions: (Apophis like object) – impact energy will not cause, why is is difficult to model

- Dynamical Characterization, Control, and Performance Analysis of Gravity Tractor Operation at Binary Asteroids
Eugene Fahnestock (University of Michigan / NASA Jet Propulsion Laboratory, United States)

Extensive study done at the request of B612 for using the GT to deflect hypothetical impactor (2016 NM4) by group at JPL, no detailed study of using GT at the binary object, apply prior GT control to case of binary, what is the differential performance penalty for binary versus solitary, 2016 MN4 – shape models from 1999 KW4, small size binary in analysis (65-24 m), placement of GT such that avoid collision and to maximize towing effectiveness, assuming SEP system, cant main GT thrusters by some angle to avoid exhaust impingent, computed ideal values (static setup to maintain equilibrium, GT station-keeping approaches, can get better control using simpler control algorithm, teo regions with good performance metrics (interior region meaning inside secondary ~ 215m, exterior region d ~ 430 m), conclusions: delta-V accumulations more likely to be near the top of their spread, mass loss more likely to be near the bottom of its spread, in relative terms there is a performance penalty compared to GT operation at solitary NEO, penalty for being exterior, completing deflection operation a binary NEO still quite achievable in absolute terms (even with simple control approach). 1999 KW4 may be typical (average period around 24 hours, KW4 is less than, KW4 is much smaller than those one would study)

- The SHADOW Mission: Deflecting APOPHIS with a Flotilla of Solar Shields
Prado, J.-Y.1; Perret, A.2; Boisard, O.2; Bertrand, R.1 1CNES (France); 2U3P (France)

Increasing number of resonant orbit with time, about 1 in 50 chance for an impact with the earth between 2036 and 2130, attempt to define safe areas for one century, SHADOW is tow parts, one is observation, another is deflection mission, Part 1: observe and track for Yarkovsky effect, Part 2: Apophis deflection by canceling Yarkovsky effect – developed in parallel with flotilla of solar shields, high Delta-V needed – useful for solar electric propulsion, Yarkovsky thesis in late 1800s, 1987 : small variation in LAGEOS, 2003 first observed in GOLEVKA, YE is tiny (10^-10) – effect like a butterfly on an aircraft carrier, main effect on semi-major axis, shadow 2 mission: transfer module using SEP carries 4x200 kg solar shields, shields controlled by transfer module, sail hovers a few km over the asteroid, no direct link of individual sails to Earth, chemical propulsion needed for balancing photonic pressure, only effective is there is substantial YE, next approach 2012/2013 must not be missed, excellent opportunity for worldwide training, solar shield/sail technology not proven, in mythology: Sun always tried to destroy Apophis, question: disagree with keyhole analysis

- Asteroid Deflection Theory: Deflection Charts and some New Deflection Options
Izzo, D.; Chy, C.H.Y. (European Space Agency, Netherlands)

New title: Asteroid Deflection Theory (Orbital Mechanics), Delta-V models are a.) full n-body propagation and b. keplerian propagation, if libration cycle tied to resonance begins, analytical methods lose accuracy, closed form solution is a formation flying problem between nominal asteroid (mother) and its deflected image (daughter), for small DVs the linearized rendezvous equations hold, delta-V use in-plane, optimal direction is along the velocity vector, optimal angle is between 0 and 1 degree for most of orbit, issue with model - linearization/integration error grows with time / accounts for only instantaneous velocity change, disregards the asteroid-Earth phasing and does not account for system design, the deflection formula (equation for acceleration and miss geometry), deflection charts: push time and start time relationships – show trade-offs given a particular encounter, but these charts do not tell us the optimal deflections, crucial to understand the strategy for system design and requirement for amount of deflection, larger deflection distance may mean kinetic impactor may be superseded by other options.

- Ariadna Encounter 2029: Introduction to the three studies
Call from ESA for ideas and concepts.

- Catastrophic Impact Energy Threshold for Disruption of Small Porous and Non-Porous
Asteroids: a Crucial Information for Deflection Strategies
Michel, P.1; Jutzi, M.2; Benz, W.2; Richardson, D.C.3 1University of Nice-Sophia Antipolis, Côte d'Azur Observatory (France); 2University of Bern (Switzerland); 3University of Maryland (United States)

Previous: NEOMAP at ESA (2004), how can we be sure that we will not destroy the body? The larger the rocks the weaker they are, at larger radius energy goes up, simulating a catastrophic disruption? Computing the fragmentation code, various types of internal structure, non-porous versus porous body fragmentation, reaccumulate to form family members, not so easy to destroy a body, first complete simulations of asteroid disruption (Science in 2001 and 2003), objects greater than 100m are rubble piles, disruption by impact of a 25 km asteroid (shape comes out similar to Itokawa), two regimes (strength and gravity) for disruption energy versus radius, for gravity regime no difference between porous or non-porous, for strength regime, porous a little more energy than on-porous, disruptive regime: largest output is 50% of target body, generate a lot of aggregate, characterized catastrophic disruption for targets of different sizes, etc., Marco Polo mission in assessment study for ESA Cosmic Vision 2015-2025 at ESA, proposed ESA-JAXA partnership, have not investigated macro-porosity of rubble piles in this same fashion, question: did we ever have an integrated small bodies (did we ever have monolithic bodies)

- Designs of Multi-Spacecraft Swarms for the Deflection of Apophis by Solar Sublimation
Vasile, M.1; Maddock, C.1; McInnes, C.2; Radice, G.1; Summerer, L.3 1University of Glasgow (United Kingdom); 2Strahclyde University (United Kingdom); 3ESA Advanced Concepts Team (Netherlands)

Years ago did a comparison of multiple deflection criteria (miss distance, warning time, spacecraft mass in orbit), found surface ablation was not as bad, nuclear blast led to in some cases unwanted fragmentation, moved on to surface ablation, first proposed by Lunan in 1992 and Melosh in 1993, Mirror Bees (media too concept), 4 month study supported by ESA ACT, study dynamics and mass estimates, solar pumped laser, if shoot are an angle – lose efficiency but avoid the plume of gas, cannot fire during the entire orbit, perturbations in orbit – required control authority, direct imaging with adaptive reflector, summary of two systems (laser and direct imaging), simulation of camera for observation, direct imaging: 1200 kg at TRL 2 including 40% propellant for the transfer (mirror diameter of 60m), laser (25% system efficiency) – mirror diameter 5m, done for Apophis, better to add more spacecraft than increase concentration ratio for same mirror size, various curves for warning times and size of bees, direct imaging required larger mirrors with adaptable shape, laser system requires smaller mirrors but more complex and requires efficiency above 20%, indirect laser pumping is more mature at his time, multiple spacecraft is better, many mirrors with low conversion factor appears to be more efficient than increasing the concentration factors of a few mirrors, question on impact of dust plume, experiments on simple rocks show that perhaps not 180 degrees of dust, Keith H.: has anyone done any calculations of absorption of that energy and verify the dynamics-concerned this is based on perfect gas models – when you have porous surfaces analysis may be more complicated, Melosh’s initial estimate indicates that effective at km sized body – will this work , perhaps competitive with 1km asteroid in terms of time to deviate and effect

- Apophis Encounter 2029: Differential Algebra and Taylor Model Approaches
Armellin, R.; Di Lizia, P.; Bernelli-Zazzera, F. (Politecnico di Milano, Italy)

Investigate differential algebra and Taylor models for 2029 Apophis encounters, , new algorithms (Improved Monte Carlo, and Close Encounter Algorithm), differential algebra: automatic differentiation technique, can be used for the nonlinear expansion of uncertainties of Apophis, third order expansion shows errors of 10 km in position, developed a DA Monte Carlo simulation, Close Encounter Distance (CED) Algorithm, a set of tools for NEO close encounters, attempt to develop faster and more efficient computational tools

- New Directions in Asteroid Deflection using Nuclear Explosives
Dearborn, D.1; Schultz, P.2; Ulrich, W1LLNL (United States); 2Brown University (United States); 3DTRA (United States)

No issues with Keith’s conclusions about nuclear option (only if other methods are not available), new work follows up with NASA 2006 report – proposed kiloton or sub-kiloton explosives on surface, you can break up asteroid (1 kiloton or less below breaking up 1 km size), reason to consider nuclear explosives – most mass efficient methods of transporting energy, plenty of tests, have been used in space, application and consequence (decades to impact: standoff/push), sources have been demonstrated, suitcase size types, LLNL have experience in making craters (290m x 100 m , ~200 m asteroid of Nevada tough), information on kinetic impactors, LLNL has 3-D codes, but use 2-D code (Langrangian Eulerian 2-D code), can put different types of properties (strength – water no strength, gravel-sand – force puts in pseudo force, can also put in porosity, never done that for meteorite in terms of crush curve, something that has porosity – early on you exceed crush pressure, want to take energy and distribute it, how much material are you really throwing out, Nevada tuff (density -= 1.9 g/cm^3), after you push something – you care about where pieces go, even when you do an impactor or nuclear – there is material thrown off – some small amount that is near original speed, approaches (decades to impact: standoff or low yield – surface emplacement), years to impact – high yield impact), standoff calculations - you need to heat a lot of mass, would like to do with neutrons versus X-rays, X-rays come in - heat first layer – that layer bleaches out – put in energy into a thin amount of mass, neutrons go right on in – for this >50% is absorbed in column density 48 g/cm^2, neutrons does not carry about mixture of elements (except for hydrogen), Neutrons – enhanced fusion, US stockpile weapons optimized yield/weight, would like something that provides a lot of neutrons – need a lot of fusion – US did that part of Plowshare program (peaceful nuclear explosions) – 35 tests, recent work looked at setting things at surface, with 0.1 kt at surface (0.38% of mass ejected, 1kt too much, 0.5 kt, 270 m body with 0.1 kt is too much – mass too low to depend know what you will get, no need for nuclear tests, real uncertainty is material properties of surface – when that energy is placed on surface how does the surface respond? Provide a dependable source to transport energy – would like to use things that were tested but now weaponized, when time scale is short if 50m is coming in then can covert to powder if just outside the moon, we have the duty to tell them what is possible.

- Using a Gravity Tractor to Help Mitigate Asteroid Collisions with Earth
Yeomans, D.K.1; Bhaskaran, S.1; Broschart, S.R.1; Chesley, S.R.1; Chodas, P.W.1; Jones, M.A.1; Sweetser, T.H.1; Lu, E.T.2; Schweickart, R.L.2 1JPL/Caltech (United States); 2B612 Foundation (United States)

Completed recently for B612, using the leverage of pre-impact close Earth approach to deflect a hazardous NEO with very modest amounts of energy, using slow NEO trim maneuvers to avoid primary and secondary impact possibilities, using rendezvous S/C images and tracking, 610 meter keyhole in April 13, 2029. Apophis test case is predicted to pass through the 2036 keyhole – impact 4/13/2036, assume it will impact for test case, launch in 2021 spacecraft, to S/C tracking and spacecraft acts as a gravity tractor, S/C again tracks Apophis, Feb. 14 2022 start tracking 580 x 15 km uncertainty ellipse, ends with 360x180 km ellipse after 60 days of tracking, GT placed 250 m from the asteroid’s center of mass along the asteroid velocity vector, five thruster configuration, takes 10kg / month for S/c hovering, 1000 kg S/C provided 1.14 x 10^-12 m/s^2 acceleration, 60 days of tracking moves Apophis on b-plane, Apophis is a unique case gets close to earth very close prior to impact, a few tens of percent could likely take advantage for gravity tractor, secondary keyholes are cm to one meter, primary keyhole is 610 m wide, secondary keyholes are more dense to primary keyhole, safe harbor could be established at zeta + 2.5 km (safe harbor around keyhole), examine the risk corridor during a slow deflection moves slowly, assume a KE impactor for beta = 2, m = 2400 kg, V = 5 km/s, if done in April 2022, deflection is 200 km change, by far the most important requirement of any successful mission campaign is warning time for carry out mitigation mission, Apophis unusual since close approach prior to impact, a pre-impact close approach multiples the effect tof earlier deflection, a deflection to avoid impact just needs to move out of keyhole, gravity tractor is a high precision procedure, GT could provide a trim maneuver

Panel Discussion

Dave Morrison: agnostic when it come to nuclear or non-nuclear, need to take into account spacecraft transportation, what is doable if you had a choice between the two methods,

Dearborn: If you were doing the standoff approach, question on altitude (putting our tons of neutrons) – could approach with fast speed, would prefer if UN passed law that all asteroids are rounds, adjust standoff time so you have right face of asteroid, “physics package” of about 100 lbs – put a seeker to reduce speed (not that much mass)

K. Holsapple: What is the uncertainty ellipse, question of getting to the right place, would want something there ahead of time

Dave. M.: No one has looked at nuclear deflection option reaching options

Alan Harris: getting caught with Apophis, Apophis is slow with the return, rendezvous with Apophis is ok, average RMS velocity is 15-20km/s, would encourage non rendezvous options (potentially proximity fuze option)

Exactly how precise time is for your detonation?
Keith H.: how accurately do you know where you are so you can have proximity fuze, radar fuze have fast timescales,

Fly multiple fast flybys, should not too focused on single flight mitigation options,

Dearborn: Aerospace did a scenario approach of hypothetical, every launch window advocated sending several options, launch them so approach at different times to see effect was sufficient

Rusty S.: Need to do a system level cost effectiveness analysis, ultimate questions- how do we best spend funds, if we look at cost effectiveness, it seems intuitive that if he takes Alan Harris size/freq. dist, most productive things I can do is to accelerate second generate of survey to the point that the unknown residual of any size NEO decreases as rapidly as possible, when invest in 2nd generation search, largest NEOS become known earliest. If we say nuclear device is needed for large object, three basic reasons for nuclear: big object at any time, smaller object getting to it rapidly – both of those disappear for all but comets – third issue does not disappear – geopolitical procrastination, geopolitical community cannot make a decision in time to use a non-nuclear method – one remain case that will not go away – ultimate geopolitical (audience claps)

K. H: most politically method is likely to be the one to be stuck with since politicians cannot decide to do anything else

Dearborn: if Tunguska sized object is going to fall in central Africa – people at UN would talk all the way down, if it were hitting for Paris – one nation might choose to do something, was not proposing to spend more money, what is the number one thing – send more money to Don Yeomans, if you want something to learn about asteroids – you need an impactor mission (Don Quixote),

Michel, P: comments by the people – most of people who want deflection mission, there is public fear of using weapons, may scientists do not want to come to this conference since they think it implies nuclear weapons, we have to be careful how we pronounce this

Dearborn: I do hear things that may scientists nuclear devices for excavation, information should be in the room, in the meeting with Tom Gehrles, the deflection dilemma – nuclear explosive – may indeed be facing larger risk to build such a system and have it ready – one needs to think very carefully whether the cure may be worse than the disease (SALT treaties, Chinese declared that they were not ready to turn in nuclear weapons for asteroids – never mind their weapons were not designed for asteroids)

Dearborn: did not advocate building anything

K.H: if anyone says we need to test a nuclear weapon, we need to understand response of the asteroid and can do that with an impactor

Clark C.: the porosity has been discussed a lot today, do not think asteroids look like piles of dust, Don David and Chapmen coined rubble pile, a rubble pile consists of hugh pieces to fine stuff (Itokawa), how are you going to kinetic or nuclear – how you are going to model the response of such a heterogeneous nody

K. H: ultimately how nigh is your event compared to the grains? Less effect than you might image (question of size scale)

Dave M.: comments on Rusty’s argument, statistically is we do survey or not, we are here that something could happen, you cannot just say statistically we cannot worry, a couple of people say nuclear is the system of choice, would think kinetic impactor is surely more easy to do – but several people said nuclear

Dearborn: if you can do it another way then do another way

K.H.: just a question of mission design, if you can do it with an impactor then do it with an impactor, perhaps solar collectors could be competitive – maybe could reach further,

Nothing like a deadline to focus, as soon as we do, everything kind of resolves, you always want a backup plan, nuclear will become less of a political liability

Alan Harris: let us not build it until we need it

K.H.: at some point someone would want to being up biggest “gun”

If you repeat the Tunguska event today, cost of real estate (300-400 M Euros over an unpopulated area) pay for a survey program,

Dearborn: with Tunguska like event, today the population is 12.5 people per square km, every few hundred years 25,000 dies, in an actuarial sense that is also the cost, with regard to where they put money, U.S./China/Russia have nuclear weapons for their own reasons – working their way down – at that point can extend out response time, keep nuclear weapons for political considerations and not for stopping asteroids,

Alan Harris: 20,000 per mean event, median = 0

A.Glavez: surprised debate is so polarized, you need several options, whenever this kind of things come, you have to have this knowledge, important to have working on a sustainable way

D. Izzo: for Apophis nukes may not the solution, coming up with different ideas

Michel, P: useful for having a demonstration mission like Don Quixote

K.H.: The engineering/mission questions are those that can be tested, what we do know for sure if we impact at certain velocity, deep impact (beta well over 100-200 perhaps), even calculations come up with ejecta velocities of beta of 30, need to know beta better, if we can hit it,

Michel, P.: we need a test

P. Gatterson: political leaders are ok are estimating risk, bit of fear mongering to talk about the cure is worse than the disease, even if you have a preference against using nuclear weapons, that is not prohibition against using it. Would add to Rusty’s case: you choose a softer touch approach and you fall back on redundancy but at least you thought through, not advocating a test mission.