This area will cover relevant news of the threat to the planet from Near Earth Objects (NEOs) including concepts and designs for mitigation. All opinions are those of the author.

17 May 2011

Article: Anders Sandberg on Progress in Mitigating Asteroid Impact Risks

Anders Sandberg, postdoctoral fellow at the Future of Humanity Institute of Oxford University, gave the keynote address at the May 9-12, 2011, Planetary Defense Conference in Bucharest, Romania sponsored by the International Academy of Astronautics. Here is his short microsummary of the event:
Microsummary: we are on the right track!
The latest estimates of the NEO size distribution by Alan W Harris retain the shape of previous estimates, a power law with a pretty steep exponent and an unexplained ‘dimple’ where there are too few 10-100 m NEOs.
Donald Yeomans showed that the impact flux from comets is small compared to Near Earth Asteroids (NEAs) (less than a percent). Satelite surveys have produced a flood of data (check out this animation or my graphs) and we have good reason to think we have already seen a sizeable fraction of the NEAs that would be serious global catastrophic risks (GCRs) - and they are in orbits that are safe for at least the next century. This has really reduced the expected risk.
The mandate from the US Congress wants a 90% completion by 2020 for the big (>140) NEAs, which might be tough unless there is some extra push (ideally a Venus orbit satelite or more time at the Large Synoptic Survey).
The LSS will be able to catch a lot of 45 m objects 1-3 months out, and people are starting to seriously look at finding smaller objects on their “death plunge” just before they hit Earth. They pose just local risk (if any at all) but as the GCR risk is retired their relative risk go up. Mark Boslough showed that some of them might produce pretty destructive airbursts. This domain also deals with the “we are going to be so successful that we are going to put ourselves out of business” problem - we are 10 times more likely to save lives by including imminent impactors in the next surveys, although the number of lives saved might be smallish.
Obama’s call for a manned NEO mission is a tough challenge, mainly because the best objects from a mission technical perspective (low deltav etc) might be smaller than the spaceship! Overall, NEO missions are maturing but the Japanese seem to be a decade ahead with Hayabusa and Hayabusa II.
Deflecting asteroids with kinetic impactors looks pretty good, but a lot hinges on the porosity of the asteroid. A fluffy asteroid just absorbs the impact, while a “hard” asteroid will eject a plume of debris that gives an extra push. Unfortunately we have no way of measuring the porosity, so plenty of talks investigated models and ways of estimating it.
Gravity tractors are wimpy, but seem to be fairly close to a realistic technology. They are pretty useless for deflecting an asteroid away from Earth, but enough for preventing it from going through a keyhole. This makes them a pretty ideal supplement for any mission. Flotillas of tractors can be more effective than single tractors. Paul W. Chodas also showed that there are “Jabbas”, robust states of an orbit that are hard to budge.
Nuclear deflection looks like it is workable, but it is definitely a last resort and mainly useful for imminent hits. Some serious issues about how to avoid dispersing loosely held together impactors. The main problem is getting the warheads to the impactor in time and to have them detonate at the right standoff distance.
Erick Ball described a real “Armageddon” scenario where a 5 km long periodic comet discovered ~290 days out could be deflected if mankind really got its act together - something we all felt was doubtful. Several other deflection methods (laser ablation, robotic rockthrowing, ion beam shepherds, painting to cause Yarkovsky effect deviations…) are investigated but not ready from prime time. Another problem is that NEOs seem to be quite different from each other, and methods that work for one type might need to be tweaked for other types.
Organisationally, things are moving forward. NEO study and defense is becoming more and more organised in the big space agencies, the UN and the US government. Some interesting notes from Frans von der Dunk on the legal aspects: check out the report “Legal Aspects of NEO Threat Response and Related Institutional Issues.”
In particular, the ‘responsibility to protect’ might apply here, requiring states to have capabilities to deal with NEO risks. There are also an interesting possible tradeoff between sharing information and doing missions in an open manner and avoiding liability: if damage occurs in the course of a NEO response states might not be held liable as long as the mission is within parameters set by proper mandate international community groups.
My own talk was about the issue of cognitive bias and rationality in impact mitigation. Basically, our biases are interfering with both the public, decisionmakers and the research community, and overcoming them is an important part in public relations, explaining the situation and doing the research. Not all of them are bad for the impact risk community: the preference for hard numbers really helps it in the “competition” with softer risks. But availability bias (it has never happened, never will) and scope neglect (a million dead are just
statistics) make many decisions rather irrational.
There are also problems with planetary defence being a public good, being long-term (it might be rational to put off doing things for a while, since tech is advancing - but this easily leads to putting off doing things too long; the “sweet spot” might be a decade, about a political lifetime) and discounting the future too heavily.
However, I think the impact community are an example to all of us dealing with other existential risks. They are doing a pretty good job. They have managed to 1) demonstrate the existence of a risk and quantify it, 2) convinced enough decisionmakers to fund preliminary investigation, 3) built a lively interdisciplinary community devoted to the risk and mitigation (with an inflow of new students carrying on and developing the thinking). Other risk communities may do well to study how they did it.
And finally, a great motto: “There ain’t no such thing as a free launch.”

Link: Article ("Anders Sandberg on Progress in Mitigating Asteroid Impact Risks")

16 May 2011

Video: Asteroid Deflection Research Center

Link: YouTube Video ("Asteroid Deflection Research Center")

Paper: "New applications of the H-reversal trajectory using solar sails"

New applications of the H-reversal trajectory using solar sails

Xiangyuan Zeng, Hexi Baoyin, Junfeng Li, Shengping Gong
(Submitted on 8 Mar 2011)

Advanced solar sailing has been an increasingly attractive propulsion system for highly non-Keplerian orbits. Three new applications of the orbital angular momentum reversal (H-reversal) trajectories using solar sails are presented in this paper: space observation, heliocentric orbit transfer, and collision orbits with asteroids. A theoretical proof for the existence of double H-reversal trajectories (referred to as 'H2RTs') is given, and the characteristics of the H2RTs are introduced before the discussion of the mission applications. A new family of H2RTs was obtained using a 3D dynamic model of the two-body frame. In a time-optimal control model, the minimum period H2RTs both inside and outside the ecliptic plane were examined using an ideal solar sail. Due to the quasi-heliostationary property at its two symmetrical aphelia, the H2RTs were deemed suitable for space observation. For the second application, the heliocentric transfer orbit was able to function as the time-optimal H-reversal trajectory, as its perihelion velocity is circular or elliptic velocity. Such a transfer orbit can place the sailcraft into a clockwise orbit in the ecliptic plane, with a high inclination or displacement above or below the Sun. The third application of the H-reversal trajectory was simulated impacting an asteroid passing near Earth in a head-on collision. The collision point can be designed through selecting different perihelia or different launch windows. Sample orbits of each application were presented through numerical simulation. The results can serve as a reference for theoretical research and engineering design.

Link: Paper reference

Link: Paper [PDF}

Paper: "Planetary Defense and an Energy Infrastructure for Near Earth Space"

Planetary Defense and an Energy Infrastructure for Near Earth Space

Fork, R.; Burgess, L.; Bergstue, G.; Gaillard, R.; Dept. of Electr./Comput. Eng., Univ. of Alabama Huntsville, Huntsville, AL, USA

Proceedings of the IEEE
Issue Date: March 2011
Volume: 99 Issue:3
On page(s): 359 - 362
ISSN: 0018-9219
INSPEC Accession Number: 11821910
Digital Object Identifier: 10.1109/JPROC.2010.2096250
Date of Current Version: 17 February 2011
Sponsored by: IEEE

The White House Office of Science and Technology (OSTP), in response to recent Congressional action, assigned National Aeronautics and Space Administration (NASA) the task of: "(A) protecting the United States from a near-Earth object that is expected to collide with Earth; and (B) implementing a deflection Digital Object campaign. A "functional analysis" of the task was recommended. A planetary defense strategy was considered to such an analysis. Using lasers in space for planetary defense and space energy infrastructure will reduce the current cost of lift to orbit, remove debris from space, assist in rescuing astronauts in difficulty, and deliver energy to other resources in space, and possibly, even eventually to Earth.

Link: IEEE XPlore

SGAC Future of Planetary Defense Video Clips

The Space Generation Advisory Council (SGAC) hosted a one day public event on the Future of Planetary Defense, prior to the start of the 2nd IAA Planetary Defense conference. These are selected videos from the event.

Link: YouTube Video ("Future of Planetary Defense News Broadcast.AVI")

Link: YouTube Video ("Rusty-about-Dorin_480p.wmv")

Posts from Bruce Betts at The Planetary Society on 2nd IAA Planetary Defense Conference

Bruce Betts from The Planetary Society had two blog posts summarizing some days at the 2011 IAA Planetary Defense Conference:

Bruce Betts reports from the Planetary Defense Conference in Romania
May. 9, 2011 | 15:00 PDT | 22:00 UTC

Day 2: Planetary Defense conference in Bucharest, Romania
May. 10, 2011 | 15:59 PDT | 22:59 UTC

Annoucement: 2013 IAA Planetary Defense Conference in Flagstaff, Arizona USA (April 15-19, 2013)

The 2013 International Academy of Astronautics (IAA) Planetary Defense Conference will be held from April 15-19, 2013 in Flagstaff, Arizona USA. This announcement was made at the 2011 IAA Planetary Defense Conference. The 2013 conference will be organized by the NASA NEO office with potential assistance from several academic institutions in Arizona. Flagstaff is close to Barringer Crater.

12 May 2011

2011 IAA Planetary Defense Conference: Day 4 Session 8

Notes from Day 4 of 2011 IAA Planetary Defense Conference. Follow twitter feed for more information:

Day 4 (Thursday 12 May 2011) Session 8
Legal, Policy, POlitical Framework for Planetary Defense

- A'Hearn
"Recommendations of the US NRC Study on NEOs"
asked by US Congress a few years ago about NEO Surveys and NEO Hazard Mitigation
released Jan. 2010, reviewed 2006 NASA report
>-8 members from study at 2011 IAA PDC
different types of personnel (nukes, anti-nukes, robotic/astronaut enthusiasts)
independent costs estimates obtained but not in time (including in written report)

1. Cannot meet congressional mandate by 2020 (written in 2009), 90% of d>140m requires new technology
2. Venue trailing orbit can be done by 2022 if funding is available ($2-3B including 7 years of operations) - NRC Ah Hoc comm advocated in-space obs.
3. probably IR but maybe in optical
4. LSST could be it by 2025, by 2030, or sonner in NEO-optimized shared mods

Survey try to find smaller object less than 140m (30-50m diameter) if font interfere with >140m objects, do not stop once you have found <140 m objects
Arecibo radar important

4 approaches to mitigation: civil defense, slow push (tug, solar heating, albdeo change, GT), kinetic impact, nuclear blast
boundary between technique is fuzzy

Q: NRC report misunderstands role of gravity tractor, Rusty: not a deflection for an Earth impact, mission for keyhole impact (necessary for every mission) - needed for all missions, keyhole deflector not an earth deflector

Q: break connection of disruption with last minute defense

- Sergio Comacho
"Progress of NEO Activities within the UN COPUOS"

talks about Action Team 14 (on NEOs) and UN CONPUOS

Report by ASE's international panel on asteroid threat mitigation
finished 30 Sept. 2008m Nov. 2008 summary presented by AT-14

NEOs preocess under a work plan - 2009 until 2011 (work carried out by STSC(and its WG) and CONPUOS, internsessionally bt AT-14

Workshop on a NEO mission planning and operations group (MPOG) at ESA's ESOC in Darmstadt in Oct. 2010

Interim report, L.308, contains an annex to the revised " Draft Recommendation for international response to the Near Earth Object Impact Threat"

AT-14 (27 members) and WG reviewed L.308 and those updates were incorporated in the interim report of AT-14 (2011-2012)

Multi-year work plan on NEOs has been extended for two more years (2012-2013)
Intersessional work in 2011-2012 could include workshops of experts on various aspects of draft recommendations made by Action Team
Intersessional work on 2011-2012 to talk about MPOG

- Boris Shustov
"National NEO Program Plans" [in Russia]
Space Council for Russian Academy of Sciences include group looking at space debris and NEOs

Two major bodies include Russian Federal Agency (Yuri Makarov) and Russian Academy of Sciences (Ministry, 230 institutions)

Space Council of Russian Academy of Sciences
Activity on NEO problem in Russia is rising
Book on NEOs, published in Russia in 2010 (written in two levels)

Need a comprehensive (federal) program in Russia on international cooperation on NEOs

draft concept of long etmer federal NEO program group prepared by Expert Working Group on ACH by the Space Council of the RAS

June 2010, special joint meeting of the heads of Federal Space Agency and RAS was held

Roscomos and RAS want to integrate NEOs and space debris, preliminary name: "System of Mitigation of Space Threats", program under preparation, complex program (detail) presented in fall of 2011

- new optical instruments for massive discovery
- wide-angle 1.6 m telescope (400-1100 nm) AZT-33VM
- space born telescope for NEOs
- includes follow-up observatories
- radar technology for NEos (Ukraine and Russian): 70m radar in Ussuriisk for study of PHO
- Space mission, pre phase A study of automated mission is completed, Phase A will be completed in 2012, study physical properties of PHA (maybe Apophis)
- put a radio beacon on asteroid (depends on Phobos-Grunt mission scheduled for launch in Nov. 2011)

Lockne meteorite crater: formed 450m years ago by impact of 600 meters

Tunguska investigation included in program

- Lindley Johnson
references OSTP letter dates 15 oct. 2010 (response to NASA Authorization Act)

Damon Wells from OSTP coordinated from presentation

US National Policy in June 28, 2010 document: first time NASA policy specifies NEO threat action, first time in such a document at such a level, provided leverage for NASA to work with other agencies
plus up from NEO program from $5M program to $20.4M program
new plans for NEO human missions by 2025

NEO threat detection:

NASA will coordinate NEO detection and threat information, NASA would include direction of public information, NASA has set up information process for threats

upon notification from NASA:
1. threat to US territory, FEMA takes lead (FEMA can only advise on evacuation)
2. beyond US territory, US Department of State facilities efforts

homework needs to be done from WH perspective on potential NEO mitigation/deflection as to maturity of who to assign it to? (NASA-unclear)

Q: in terms of mitigation, who is leading within NASA
A: see the OCT put it in one of their calls, needs still to be organized: what is the outcome of the PD task force: has not been decided by the administrator: hope can announce at LPSC next year, perhaps not under one directorate, opportunities under Science and Space Exploration, and maybe technologist, may need to be a PLD coordination office to keep a focus on the activity

News Article: NASA's Dawn Captures First Image of Nearing Asteroid [Vesta]

Image obtained by NASA's Dawn spacecraft of the giant asteroid Vesta in front of a background of stars. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

This image, processed to show the true size of the giant asteroid Vesta, shows Vesta in front of a spectacular background of stars. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

From the article...

NASA's Dawn spacecraft has obtained its first image of the giant asteroid Vesta, which will help fine-tune navigation during its approach. Dawn is expected to achieve orbit around Vesta on July 16, when the asteroid is about 188 million kilometers (117 million miles) from Earth.

Link: News Release

Video from NatGeoChannel Known Universe simulating the impact of a large asteroid

L:ink: Video

2011 IAA Planetary Defense Conference: Day 4 Session 7

Notes from Day 4 of 2011 IAA Planetary Defense Conference. Follow twitter feed for more information:

Day 4 (Thursday 12 May 2011) Session 7
Student Session

- Charlotte Norlund
"NEOMiss: A New Earth Object Devision Support Tool"

Looking down at Earth, tool for investigation human vulnerability, uses the physical simulator used in NEOimpactor and NEOSim, previous work by Nick Bailey

includes uncertainties in model and data, uses a Monte Carlo approach, vulnerability models made for five land impact hazards, multi-hazard simulator, only looking at land impact and not water impact, behavior-based evacuation models base don US hurricane model
uses global gridded data (1x1km grid)
transportation: car, moped, walking options
National infrastructure: uses OpenStreetMap data (source of infrastructure data) and created gridded road network capacity and flow times
San Jose, CR evacuation simulation: evacuating an area north of San Jose is a challenge: 3.5 days is not enough (15% manage to evacuate)
An average of 2% of population in the affected area will be causalities along the Apophis risk corridor

Q: issues of different roads
Q: issue of different human perception
Q: issue of temporary or permanent evacuation

- Farnocchia, Davide
"The performances of A wide survey on a population of impactors"
deep survey: large objects >140m and large distance (0.5-1AU) for large warning time
wide survey: small objects < 140m, visible during close approach, wide field of view

Wide survey is a possible European asset (limited superposition with US surveys, significant NEO discovery rate)

survey stations: 4 survey stations (limiting mag from 23 and 21.5)
tracklet: set of observations in a short time span, need at least three tracklets for orbit

Q: issue on ecliptic region and looking for impactors there.

11 May 2011

2011 IAA Planetary Defense Conference: Day 3 Session 6

Notes from Day 3 of 2011 IAA Planetary Defense Conference. Follow twitter feed for more information:

Day 3 (Wednesday 11 May 2011) Session 6
Mission Planning and Technologies

- Housen, K.
"Measuring the Momentum Transfer for Asteroid Deflection"
crater profile does not depend too much on void spaces
impact disruption of spinning bodies
rapid rotators will be more susceptible to disruption in a deflection mission
Beta for sand at 2km/s is 2, 10-20km/s for beta=3
beta may depend strongly on porosity

- Golubov
Influence of intermediate scale structure on Yarkovsky and YORP effects
YORP first pointed out by Rubincam
Asteroid Itokawa doe not demonstrate YORP model

- Andrew Klesh
Improved Navigation Techniques for Asteroid Landers and Impactors
based on JAXA work, Hayabusa 2 work

landed accuracy: NEAR (several hundred meters), Hayabusa, Marco Polo (3.5 n), H2 (several tens of meters)

Tracking features may not be an option
navigation by radio ranging

- Bombardelli, C.
"Ion Beam Shephred: A New Concept for Asteroid Deflection"

Ion Beam Shepherd (IBS)

primary ion engine pointed at asteroid surface, secondary propulsion to avoid IBS from drifting away from asteroid
currently under study by ESA and TU Madrid for space debris removal applications
beam divergence: need to make sure beam does not expand too much
for example. taking SOA thrusters, get 5-15 degrees and March of 20-30, handle 150 m diameter asteroid from a distance of 200m or less from center (50 m from surface)
force transmitted: penetrate asteroid surface a few nanometers, backsputtering is low
can beam pressure damage asteroid: local beam mechanical pressure: for example for 100m diameter asteroid, a 10N beam gives a peak pressure of less than 6mPa
for one year of thrusting have a Isp - 9000s
with Isp = 3k seconds
for asteroid below 500m gravity force is low
slow push asteroid deflection performance,
case: 2007 VK184 (D=130m)
1 N thrust for 2 years = 5 MT IBS (3000 sec Isp)
Gravity tractor needs more mass for same effect as IBS (50 MT needed for 150 m asteroid)

- Hayabusa2 Mission (Yoshikawa) - presented by alternative
has become project (Phase B)
budgetary request for H2 project was approved, on May 1, 2011 status of project becomes Phase B and under PDR (Preliminary Design Review)
C-type (1999 JU3) target now
0.922 km , around 1km in size (not irregular)
Spectrum is different
Launch of July 2014, arrival in June 2018, 3 samplings (sample, crater, and 2 samplings), reath return in 2019/2020,
500 m altitude release, canister will explode with projectile release, spacecraft will fly over crater and take sample)
small lander (MASCOT - under discussion): DLR/CNES MASCOT (10 kg lander) Mobile Asteroid Surface Scout
NASA: similar as H1
international collaboration may be possible

Canadian NEOSSat at 2011 IAA Planetary Defense Conference

Canadian NEOSSat (Near Earth Object Surveillance Satellite) at 2011 IAA planetary defense conference

Fully funded PhD in asteroid deflection research at Univ of Surrey in UK

Fully funded PhD in asteroid deflection research at Univ of Surrey in UK

Aerospace Corp developing web based first order asteroid deflection / kinetic impactor design tool

2011 IAA Planetary Defense Conference: Day 3 Session 5

Notes from Day 3 of 2011 IAA Planetary Defense Conference. Follow twitter feed for more information:

Day 3 (Wednesday 11 May 2011) Session 5
Campaign Planning

- J-T Grundman
AsteroidSQAUDS/iSSB - Synergistic NEO Deflection Campaign and Mitigation Effects Test Mission

reflection of past IAA 2009 conference white paper: campaign studies and focus on smaller objects
looking at desires of various missions: heavy launcher development, fast mission scenarios, low space debris generation, include amateurs,
small and smart interceptor design produced in advance of heavy launch vehicle development
launcher test schedule triggers search for suitable target (3-6 months to launch)
every month 8-20 known NEOs approach Earth within 0.2 AU
NEAs about the size of 100m chosen
instruments: ranger like camera bank, dust counters, plasma instruments
take the AsteroidFinder spacecraft
have a more modular approach to spacecraft development
using CEF (Concurrent Engineering Facility)
put a kit together
interceptor: 179 kg mass
fits in standard secondary payload volume
took a Ariane 5 model for heavy life (12 MT to GTO)
20 impactors on a launch vehicle
Use Shoemaker Levi 9 multiple impact scenario

Q: need for observer spacecraft for any deflection
A: not about a proper deflection (testing mission) - not a deflection

- A. Zimmer
"Target Selection and Mission Analysis of Human Exploration Missions to NEAs"
Univ. of Stuttgart

complex trade space, multiple NEAs too many filers, launch window investigation, mission abort options
better understanding of parameter space for trajectory options for human missions

accessibility model: pre-selection of asteroid, based on celestial mechanics rather than scientific gain
approach: based on upper stage performance, departure from LEO, two impulse round trip mission, termination condition: deltaV limit (first burn) <10k/s, mission duration <365 days

verification of model: used 7812 NEAs, size criterion (H<=25) and slow rotation rate, 6704 NEAS, then semi-major axis, eccentricity, inclination: 2567 NEAs, then termination condition:
left with 240 NEAs between 2010 and 2040
statisitics: most attractive tragets with deltaV<7.5 km/s left with 73 targets - most of PHAs, pre-dominantly Atens and Apollos, many targets require long missions and high DeltaV
absolute mag less than 22-only about 20 NEOs

170 launch windows between 2020 and 2040
gradually increase in mission duration and then increase time with 1 mission every 2 years
looking at anytime abort (duration of return to Earth minimized) and free return (delta V minimized)
only investigated outbound mission leg only (once at asteroid)
long missions (= 365 day return, free return possible, anytime abort is limited)

better understand of abort options and assessment of prx ops, and Near Earth Largrnage points
design a building block of architecture

- Sugimoto, Y.
"Effects of NEO Composition on Deflection Methodologies"
Univ. of Glasgow

Looking at short warning time cases
for small bodies mass is not always available and estimate from bulk density if highly unlikely
most abundant NEOs are S-type asteroids (about 50%)
evidence theory can quantify epistemic uncertainties without assuming a distribution function specific to asteroid composition
NEO properties: micro-density, micro-porosity, bulk porosity, and albedo (out dist. on those)

two measures of uncertainty: beliefs and plausibility
set scene, set a baseline composition: 40% bulk porosity and 3.6g/cm?^2, and 0m2 albedo
deviation required (1.66 Earth-radii and 2.5 Earth-radii safe distance)

three types of mitigation missions: kinetic, nuclear, and solar collector
Q: did listing of meteorite densities did it include all data: did not include data, only a fraction of data are usable since meteorites have been weathered and potential better samples needed that are less weathered and handled better
Q: what is important is physical properties

- Cyrus Foster
"Multiple Concepts and Operations for Asteroid Mitigation including Multiple Gravity Tractors"

Deflection campaigns uses more than gravity tractor
redundant gravity tractor for insurance against failure

how does deflection scale with use of multiple gravity tractors
three concepts: single gravity tractors at a time, simultaneously tractor GTs w/station keeping, simultaneously tracting with mechanical docking to form single gravity tractor
used Apophis
looking at six launch opportunities: sending single 1MT gravity tractor

Concept 1: single GT at a time
other GTs an acts are tracking and use as backup
simpler operational concept but poorer deflection, total deflection of 76.1 km

Concept 2: simultaneous GTs
station keep around single point (could also be interested in halo orbits)
enables simultaneous ops but
total deflection of 122.4 km

Concept 3: mechanical docking approach
eliminates strict station keeping requirements but requires mechanical interface and docking ops

Concept 3b: keep empty gravity tractor docked
total deflection of 134.6 km

for Apophis: docked stacking provided a 10% improvement,

Trajectory Browser Tool at NASA Ames (web based tool to search rendezvous opportunities)
transfer from Earth to 8k NEOs and user can access database and select constraints
database of 2 body ballistic trajectories for various missions configurations

Mission Design Center Small Body Missions at NASA Ames
currently a NASA internal website

Q: perhaps increase efficiency for concept 1 if one if to use expended GT is sent

Q: use kinetic impactor and GT to trim perhaps, that might be easier
A: for Apophis multiple gravity tractor is overkill for this example (just providing it for example)

Q: how robust is the scenario are, launching GT at different times, putting GT later

Q: Looked at refueling GTs
A: Have not considered

Q: is the NEO tool distinguish types of NEOs based upon quality of observations
A: Yes, have orbit condition code as user input

- Nahum Melamed
"Development of Handbook and an online tool on Defending Earth against potentially hazardous objects"

develop a handbook for kinetic impact
develop a web based resource center for first order deflection mission requirements
aid in KI design

characterize NEO, determine deflection maneuver by using Lambert solution, select launch vehicle, determine deltaV, determine B Plan position
currently development B plane position is finished, working on the determine the trajectory phase portion
available on JPL portal at future stage

Current state of the web tool (Phase 1a)

ongoing development, save and retrieve buttons, B-plan updates, add variable resolution on earth impacts, possibly to vary to DeltaV slides, show keyholes,

Phase 1b development:
integrate with launch capability and use LV payload planners guide, use Lambert solution to connect departure, get DeltaV to imparted NEO

tool ready in a could of months

- Andres Glavez
"ESA Asteroid Mission Studies: What we have learnt"

Don Quijote was an interesting exercise

how can a generic precursor be defined? complicated missions, many options, have freedom how to select a target (not like reality), multiple trade-offs in architecture

clever use of orbital mechanics (Don Q. Mission): dual launch with spacecraft separated into different trajectories
flexible mission timelines
orbit stability
be prepared for the unexpected
mission layer is related to the type of information mission is expected to gather

radio science experiment: requires iterative process with determination of position and computation of position of asteroid

- Sam Wagner
"Robotic and Human Exploration/Deflection Mission Design for Asteroid Apophis"
Human mission requirements for 180 and 365 day crewed mission
2028/2029 human mission
two launch windows for each close encounter
180 days is the max for most NASA missions
for 2028/2029 launch dates, very small launch windows (2-12 days)
180 day summary, need 12 km/s
365 day mission: lower Delta V required, 6 km/s deltaV needed, similar to Ares I with Orion
Use Apophis for NEO missions, similar to Lunar deltaV with 6.5-7 km/s

Fictional crewed 2036 deflection missions: minimum one year mission length, 8.5 km/s deltaV
launch window exactly one year prior to impact, arrival 15 days prior to impact (only one chance)
Apophis arrival, departures, Earth arrival in last 1.5 months

Fictional post 2029 Intercept mission
continuously launch from 2035-2036, max deltaV is 4 km/s
arrival velocities from 0.09 - 20 km/s

Human pilot Mission Conclusions:

180 day mission: 11-12 km/s
365 mission: 6.5-7 km.s

- Erik Ball
"NEO Object Interception Using Nuclear Thermal Rocket Propulsion"
in place of Steven Hoewe

Scenario: Need to deflect large long Period Comet (10 km)
deflection or destruction

minimum energy for example is 3300 terajoules, thermonuclear explosion
NTR is very useful for such applications, CSNR worked on such NTRs,
chose NTR since high specific impulse (engine T/W, 6:1) up to 1000s ISP

yield requirements for deflection: scales linearly with comet size (effect based on comet properties are unknown), effects of trapped volatiles
surface burst or close standoff
40km/s: penetration impossible
Beta assumption: 3X10-4 (kg*m/s)/J
hundreds of megatons for large comet

independent variables: time of launch, angle of launch, rocket delta-V

optimize trade off between high mission deltaV and high payload mass
choose best engine size (larger engine is more mass but more thrust reduces gravity drag)

how crucial is an early launch (fast mission: 50 days before impact): high deltaV, later launches (12-27 days before impact) have 20-40 days for launch windows
early interceptor have a high fuel mass, low fuel mass but high payload mass, optimal point at about 17 days before impact (0.25 T/W of interceptor rocket)
Chemical rocket not a feasible rocket because mass to LEO is very high for chemical
even low thrust is too massive and not enough thrust for short time
3600 MT in LEO (very massive

how big could we deal with (21 HLLV in 2-3 months, carrying 20 MT interception - 1 MT is engine, most if fuel mass), 9 MT of payload, arrive at comet within 2 days of each other (7-8 month flight time), mission deltaV is 7 km/s

perhaps may be able to get up to 5 km diameter in terms of mitigation with feasible approaches
need to have technology ready perhaps

NASA Ames Mission Design Center web based NEO browser tool to search pre computed trajectories

NASA Ames Mission Design Center is developing a web based NEO browser tool to search pre computed trajectories, database of 2 body ballistic trajectories for various mission configurations, could also filter by orbit condition codes, currently a NASA internal website but plans for public release

Image: twitpic

Andrew Bacon from SGAC on Romanian TV talks about NEOs, during week of 2011 IAA Planetary Defense Conference

Amenintarea din cer - va fi Pamantul distrus de un ASTEROID URIAS? CrimeTime Live Show pe

Link: PrimeTime

10 May 2011

2011 IAA Planetary Defense Conference: Day 2 Session 4

Notes from Day 2 of 2011 IAA Planetary Defense Conference. Follow twitter feed for more information:

Day 2 (Tuesday 10 May 2011) Session 4
Impact Consequences and Education

- Longo, G.
"Consequences of the Tunguska Impact and their Interpretation"

more than 100 theories of Tunguska event
many expeditions, 1991 Italian expedition to collect wood samples
new map obtained of 1908 treefall

from final traj. azimuths: single body trajectory or multiple bolide formed by two bodies
New hypothesis: Tunguska bolide underwent fragmentation or was a double body (perfers double body)

example crater to look at Carancas Crater

Lake Cheko: something perhaps under bottom of lake (reflection) (historical evidence refers to lake Cheko but not lake Cheko)
Several surviving trees have in 1908 an inclination toward the lake

Before 1908 think there was a forest before at the current lake location

Would like to drill to bottom of Lake Cheko - do not have the money to drill (but have plan), hopefully in the next decade can drill

Q: Good to scrape enough particles (take logs apart), if get enough cromium could do isotopic analysis - could prove extraterrestrial nature

A: Have nanograms of particles in tree resin: possible consequence of body but cannot confirm (need to drill to bottom of Lake Cheko)

- Martin Mueller
"Creating Awareness" of the Impact Hazard
Univ. of Eichstaett-Ingolstadt

meteorite impact and their influence on human society are part of geography curriculum
interviews with experts and surveys of youth in Germany

the interest in meteorite impacts is above the expected average
both boys and girls are equally interested (not expected since boys more interested in natural disasters)
the interest is much higher in the 5th grade than in the 11th grade
for students, the issue of meteorites impacting today and consequences of a large impact are of highest interest (than pure natural science)

the more complex the concepts are they then are more in the way scientists think (perhaps specific to Germany)
students gather their knowledge from school and TV/movies
students do no know "nuclear winter"
students unaware of asteroid/comets
students do not know a single crater by name
most students are unaware of the geological timescale (missing a deep time framework)
two fundamentally different concepts could be identified" "hot stone in Earth orbit"

Have developed a website called CRATER with online calculator

central aim of future educational activities, covered best in geography classes

- Gritsevich, M.
"New Classification Scale for Impact Consequences"
MSU, University of Helsiknki (Russian Federation)

more reliable scale
non-dimensional parameters for asteroid entry

alpha: aerobraking efficiency
beta: fraction of KE to effective destructive enthalpy
u = meteorite rotation

- Mark Boslough
Airburst Warning and Response

looking at modeling airburst less as a point source, effects on ground greater than as point burst, policy implications of where community should go

LAA (low altitude airburst), talking referring to Harris event/mag chart and how difficult to visualize, reason airburst has gained interest is that larger objects have been mostly found

Two types of airbursts (Tunguska free fall and Libyan Desert glass)
nuclear airburst is a bubble, but asteroid energy is carried downward
Type 1 Tunguska airburst: fireball in sky, blast wave hitting ground
Type 2: fireball all the way to the ground

Kind Tut's scarab dung beetle - carved out of Libyan desert glass (referring to Anders Sandberg reference to searching for academic terms)

1908 Tunguska airburst 5 megatons (also trees potentially unhealthy so lower wind speeds could caused damage)

uncertainty quantification required

IPCC likelihood Scale - refer back to this for impact threat
politically relevant time scale is a decade (think in decade times of scales)
not paying attention to public concerns
probability of biggest impact in a decade - number of people - total number
integrates to 1363 (1409) deaths/year
current assessed threat = 126 (152) deaths/year
Future (after next survey) = 5 (17) deaths/year
point (non-point) values

we are going to be so successful that we will put ourselves out of business (for the next hundred years) - good news for humanity and bad news for this community

relative threat from airburst is increasing
100 Mt will dominate threat after current survey
mitigation should focus on small (~100m) NEOs

probability of an airburst in the next decade is about 1% (1 in a 1000 event) - Tunguska like
Probability that asteroid >140 m will be discovered in the next decade is on a collision course in the next century is about 0.1%
we are ~10 times more likely to save lives by reducing imminent impactors in the next survey

Evac plan needs to include uncertainty in size

NRC report: death lunge recommendation: next dangerous event is an airburst from <50m object, not a crater forming event

Proposed Bucharest style Airburst scale from 1 to 5

Research and Entertainment: TC3

Who would be willing to fund to witness the next TC3.

- G. Gisler, "Calculation of Impact of a Small Asteroid on a Continental Shelf"

should not call asteroid tsunami's tsunamis
what is the smallest size asteroid we need to defense against (200 m asteroid)
in Granada advocated: that is Apophis was targeting middle of Pacific because let it fall, well instrument with assets, to understand effects

of the ~200 recognized impact craters worldwide, very few are in the ocean (most on shelf)
tsunami deposits would be a sign of deep water impact
diameter of asteroid has to be 1/5 of depth of water

doing a continental shelf impact simulation, 200 m asteroid into a 100 m + 100 m sediment layers, 526 MT, used sage code with 1.5 m resolution using 200K of CPUs for 165 seconds of physical time

sediment-laden storm surge washes ashore with sand-blasting winds

Atmospheric effects from cont shelf are worse than impact tsunami, damage by blast wave and hot, fast winds
sediment laden surge is similar to powerful tropical storm
sediment on the shelf i lofted and then propelled by winds

propagation distance: 200 m impact (do not want to be 100km-200 km distance)

hydrocarbon finds craters on shelf (propitiatory data): lots more impacts on shelf

shelves are ideal for collapse and get most of tsunami like events

- Dragos Isvornau
"Dynamics of Tsunamis Generated by Asteroid Impact in the Black Sea"

- Verant, J.L
The protective role of Earth's atmosphere against the threat of asteroids"

SGAC Public NEO Event prior to the 2011 IAA Planetary Defense Conference

The SGAC held a public event on NEOs prior to the 2011 IAA Planetary Defense Conference.

Link: Video

2011 IAA Planetary Defense Conference: Day 2 Session 3

Notes from Day 2 of 2011 IAA Planetary Defense Conference. Follow twitter feed for more information:

Day 2 (Tuesday 10 May 2011) Session 3
Potentially Hazardous Objects: Recent Progress

- P. Michel
Cote d'Azur Observatory
Physical Properties of NEOs that inform mitigation

For all mitigation concepts needs size/mass, rotational properties, and shape

For kinetic impactor and nuclear concepts:
needs surface and subsurface properties and internal structure if disruption is the goal

Most NEOs are rubble piles
very small asteroids have fast spin
material properties may involve microporosity

- Amy Mainzer
NEOWISE: A new infrared views of the NEOs and the Solar System

Wide Field Infrared Survey Explorer (WISE), astrophysics mission
40 cm in diameter, solid hydrogen cryostat
expected life of 10 months, surveyed entire sky two times
4 imaging channels
525 km LEO circular orbit
lots of coverage of data over poles
2009 Dec 14 launch Delta II
thermal infrared for asteroids gives physical parameters
get diameters quite accurately and albedos
NEOWISE funded by NASA Planetary Science, archive and store exposures to public, created an archive of individual objects and tool for accessing moving objects
WISE moving Object Pipeline (WMOPS) derived from PS MOPS
Survey began in Jan 14 and started delivering Tracklets in March to MPC
Needed to see objects five times to say it was detected

157K objects observed, 34K objects
585 NEOS observed, 135 discoveries (including 17 PHAs)
1500 Trojans, 123 comets observed, 20 discovered , 20 centuars and SDOs
NEOWISE will not meet congressional mandate
NEO orbits for ~2 weeks before uncertainty becomes large for follow-up
Amateurs helped in follow up
NEO Science: get orbital distribution
carrying out thermal model of objects
used NEATM model
diameter can be determined to +/- 10%, albedo to +/- 20%
Survey biases need to be understood
run items through simulated surveys to determine size and albedo of NEOs

First data release: 14 April 2011 (57% of WISE data first pass) final data release: March 2012
NEOWISE is proof of concept for larger NEO survey, NEOCam

Near Earth Object Camera (real asteroid mission)
Discovery Mission Proposal in 2006/2010
Study NES and asses risk
detect and characterize 2/3 of all PHOs < 140 m in 4 years NEOCam selected for 2011 Discovery selection for technology development Q: hope for additional discoveries in data A: yes, could potentially find new objects after data analysis, more things in database coupled with follow-up excess of high inclination NEOs - WISE could potentially answer question on high inclination NEOs - Lance Benner Radar Tracking and Near Earth Object Characteristics JPL, uses data to provide shape models and physical models, rotation characteristics cumulative presentation from multiple people, including Steve Ostro (worked with him from 13 years) radar can spatially resolve objects 4 meter resolution, exceeds any ground or space-base optical telescope, estimate 3D shapes, proxy for spacecraft missions, identify binary and ternary objects (2/3 of such objects identified by radar)- can estimate mass and bulk density, can back out albedo, improve orbits, very precise and can shrink drastically for new NEOs, 1E8 doppler precision, radar ranging can improve orbits can reduce uncertainties by Arecibo: 305m (within 20 deg, can see 1/3 of sky, 1 MW of power, can see objects double of Goldstone, 7.5 meter/pixel), Goldstone: 70m (2nd most sensitive radar, fully steerable, sees 80% of sky, 4 meter/pixel), higher complimentary Status of Arecibo: NASA funding of $2M annually started in 2010, observatory will stay open, NEO radar program is expanding significantly, radar offline for several months due to equipment problems (equipment problems, results of insufficient maintenance perhaps, missed many targets), at least through June or longer (transmitter system got wet because of seal), new generators: resume transmitting 900 kW at regular basis (5-6 years ago, get 700 Kw, one year ago got 100 kW), higher science return, requesting three times as many asteroid targets as three years ago, two new klystrons, Goldstone: new 4 meter chirp resolution, 5x finer than previous resolution of 18.75 meter resolution (over one year ago) - also 7.5/15/30 m resolutions Offline from March - Nov 2010 for scheduled maintenance, some people doing repairs caused damage, pointing problems since Dec. 2010, return to regular service in June 2011, tracking problem last week, work is underway to increase priority of radar 272 NEos observed (20-30 detected annual, ~5% of what could be done), have observed 2 meter object (smallest object seen) EPOXI Mission target flyby of rComet Hartley 2, also Hayabusa mission support 2010 JL33 (2 km object), Dec. 12 observation from Goldstone Have made shapes for 30 objects from 272 NEOs observed If have 3D shape then can do other things Have observed Yarkovsky effect by radar ranging of Golevka YORP effect detected for multiple objects New 3.75 meter resolution (2010 AL30, diameter of 30m), spatially resolve tiny NEAs, up to 5x radar astrometry, finer shape and surface detail - Emel'yanenko Institute of Astronomy, RAS (russian Federation) Orbital Distribution of NEOs Feb. 18, 2011: 7665 NEOs (q<1.3 AU) - A. Milani 1999 RQ36 Impact Risk Monitoring the Long Term Yarkovsky Effect Univ. of Pisa Have ebeen doing routine work for 12 years for assessing NEO impact monitoring Goal was to obtain follow up observations. May 5, 2011: 310 risk files (asteroids with known impacts in 80-100 years), 317 in NEODyS-1, 369 in JPl SENTRY, 359 in SENTRY version 2 why different and why such a long list? Risk File: list of potential risks and impact probability over time 2010 RF12: next TC3 type object in 2095 (small) What is the impact probability that is appropriate to give to the decision makers. If want to get to from 10-7 to 10-9 in terms of impact probability calculation - need $750K of extra computers, practical impact of impact probability confidence level 91 NEAs with H<25, 198 H >25 have been lost
What is the meaning of lost NEAs with VIs?
two largest asteroids 2010 AR85 and 2010AU118 are extinction level events that WISE found but no one else has found them
Follow-up system does not work (list remains polluted) with dangerous asteroids we cannot remove, these discoveries of VIs that are lost has not contributed to reducing risk
system is not working because of this

Q (Alan Harris): Vi created to make where one has to look for impact
A: Problem is that there are many orbits one as to look at (too many) 5000 VIs, requires significant "negative" surveys

- Steve Chesley
Asteroid Impact Hazard Assessment Over Long Time Intervals
new title: Asteroid Impact Hazard Assessment and Yarkovsky Effect

developed SENTRY system
Italian, California, Hawaiian NEO "Mafias"

two case studies: Apophis and 101955 (1999RQ36)
Apophis has stiff integration in 2029 (scatters) and poor Yarkovsky knowledge - short term prediction issues
RQ36 smoother dynamics - long term prediction case study

Apophis impact probability updated: improved data treatment, astrometry updates

Apophis update: new keyhole appears for 2068
2036 keyhole is 7 sigma away
new Keyhole in 2068 2m across

Yarkovsky target plane uncertainties: 190km from astrometry and 500 km from Yarkovsky, thus now it is important

don't know parameters for Apophis Yarkovsky (conductivity, density, diameter, obliquity)
put distribution on above four parameters - get semi-major axis drift rate distribution - add that into trajectory, Yarkovsky skews towards keyhole
putting uncertainties on probabilities
2036 potential impact is not ruled out (more than 3 sigma away, IP = 4X10-6 impact probability)
reasonable to expect 2036 impact to be ruled out soon, 2068 is likely o persist longer, recent data in March 2011 on Apophis but does not change data - such a good orbit so new information has not changed situation

1999 RQ36

target of OSIRIS ReX mission (0.5 km)not hazardous now but 150 years from now potential for impact, have radar and other data

RQ36 has 1 in 1800 impact probability in year 2182, really? Arecibo observations should reduce uncertainty in semi-major axis drift rate, fractal structure that makes it difficult to rule out possibilities of impact, see more into the fractal structure as more observations,

- Peter Veres
The Search for Earth Impacting Asteroids by Pan-STARRS
Comenius University (Slovenia) - post doc at Hawaii in future

Feb. 28, 2010 Slovakia
May 4, 2011, meteorite fall in Poland
How efficient would PS1 be for finding an impactor

Survey simulation for Pan-STARRS from 2011-2013
pop of 130K impactors in simulation
after 4 years of observation 10% chance of finding 2008 TC2 analogue in 4 years, large impactors identified within 2 years

ATLAS telescope (2 telescopes, 100 km distance from each, each has 4 scopes, to see parallex, potential to find objects that are close and small, might cover entire sky)

- Paul Chodas
Keyholes as Providers of Deflection Leverage
phrased "keyholes"

How pre-impact close approaches impact deflection strategy

Apophis 2029 close approach, how typical is keyhole scenarios

keyhole started in 1999, B. Marsden proposed future years
how far does a keyhole go?
Apophis close approach scenario is very rare, has very high leverage for close approach
dynamics of close approach when thinking about mitigation missions

Jabbas: big fat area in the pre-impact b-plane at which the close approach produces a compression on the Line of Variations, 15 to 60 lunar distances, jabba widths are less than 1 lunar distance but they can be as wide as several million km

25% of impactors have keyholes reducing deflection within 25 years of impact: interesting

fly-by anomaly not modeled for asteroids (have seen for S/C)
folding does not change impact probability per se but moves into future
not really a fractal, MOIDS get off the Earth - finite expression of fractal, partial view of infinite view, limited view of chaos

09 May 2011

2011 IAA Planetary Defense Conference: Day 1 Session 2

Notes from Day 1 of 2011 IAA Planetary Defense Conference. Follow twitter feed for more information:

Day 1 (Monday 09 May 2011) Session 2

- Alan W. Harris
"Update of Estimated NEO Population and Current Survey Completion"

working at small company (MoreData!) and consultant to NASA/JPL NEO program office
estimate population by re-detection ratio (how many you find versus that you have already found), bias correction from computer surveys, and extrapolation to smaller size
results are getting boring since numbers not changing too much, estimate of population through July 2010
re-detection ratio from Mag 23 to Mag 16 on chart of size and number (compare fraction of new discoveries versus total), "r" = re-detection ratio will always be a higher number (getting bias correction is needed), re-detection limits are large end since found many of them (not good are factional probability for low probability numbers), for small objects % of re-detection is very low, go to computer sim of a survey, make a sample survey and look at various size ranges and compare with actual re-detection ratio,

LSST gets 1 week warning (2008 TC3 type object), current surveys give 50-50 chance for those things in a few days prior to impact

Q: Bias in MPC, scoring algorithm from MPC - some bias?
A: Surveys have to be tuned to be quick, would not rely on MPC confirmation page to do that if looking for the short term impact, on calculating existing population using MPC data - things off confirmation page but keep information

- Don Yeomans and Alan Chamberlin
"Comparing the Earth Impact Flux From Comets and Near-Earth Asteroids"

Define Long Period Comets (LPCs) wild cards of impacting population, period > 200 years, not active until inside Jupiter, takes only 9 months from Jupiter to Earth's orbit, could strike at 51 km/s, 3x that of typical NEO, impact energy is about 9 times that of similar NEA, comet densities are 0.6 g/cm^3 (given this, energy of LPC is only 2x of NEAs)
Compact impact flux study in 1984: rate of comet finding during telescope era was constant (even with increasing technology), average interval between collision is ~43 M years

Also looked at direct date from JPL NEO database, close approaches of comets/asteroids = 0.1%

For current surveys NEAS are important, once the next generation survey is complete, then perhaps comets are next

Largest PHA is Toutatis (5km)

- Ed Beshore
Univ. of Arizona
The Catalina Sky Survey, Past, Present, and Future
PI of Catalina Sky Survey
started in 2002 in NEO business, took over as PI for Catalina

started as an undergrad research project with Tim Spahr, Steve Larson, Carl Hergenrother, John Brownlww, used films in 1994 at start, 3 telescopes:

Mt. Bigelow, AZ (0.7 m Schmidt), routinely used for 24 nights around new moon, around 20th magnitude as 1.2 sigma, 2.5 pixels, in the survey business, coverage is everything, telescope has fallen into disuse,

Mt. Lemmon (1.5 m) reflector, around 22th magnitude, fell into disuse, and took over,
Siding Spring, AUS (0.5 m Uppsala Schmidt), around 19.5 magnitude,
Use identical cameras for all telescopes, 14 second downloads, CyroTger cooling, do not use filters

Base survey on pre-defined fields, 4 images 10 minutes apart, one observer will looks at 6k 3observations per night,
Continuous refinement pays off in development

Many false detections are stars in background, limiting mag. is approx. ~19.5.
Faster focusing, auto refocusing, 30 minutes spent calibrating focus using automation
Dedicated Follow up telescope, on some evenings spent a lot of time on follow-up,

Moving to next generation sensors: 10.5x10.5K CCD, increases coverage by 2.4x
Small binocular Telescope (MMT 6x1.8 meter mirrors - available in dry storage)

3 Small binocular telescopes, 23.3 Mag (3 units) could be largest dedicated to NEO search, 26 months total cost of $30M for all three systems

- Richard Wainscoat
Univ. of Hawaii
"The Pan-STARRS search for NEAs: present status and future plans"
1.8 m diameter, gradual improving in efficiency, discovered 80 NEas, long term is to
1.4 B pixels (giga pixel camera), 3 GB per image, one image per 30 seconds, 3 TB per night,
operated by a consortium, many aspects of astronomy, nearly all observations are suitable for NEO detection
Camera has 60 CCDs, 56% is survey of visible sky, 5% spent on NEO sessions dedicated
Stellar Transit Survey starting this month looking at adjacent fields,
Data processing and NEO candidate review, false detections are problem, humans screen
Do not follow up on NEO candidates
Losing quite a few NEOs, latency in image processing contributes
Fast moving objects are being lost
Jan 30 used whole night for NEO search, found 19 NEos and 1 PHA, 3 fast movers were lost
3K-6K asteroids submitting per night to MPC
A NEO discovery anticipated of 40 NEOs per month
Bad weather in Hawaii (La Nina weather patterns) causing issues
Future: reprocessing of old images using new processing to start, detection of fast moving NEOs from aligned trails in pairs of observations
Can produce image of static sky, subtract static sky to achieve 0.4 mag. gain, more fainters NEOS to be detected, Pan-STARRS 2 would have better camera - most of funding is there, PS 4 on Mauna Kea. MK is better sight than Haleakala.

- Jones, R.L.
"NEO Detection with LSST"
Univ. of Washington

Large Synoptic Survey Telescope (LSST) multiple science drivers
big primary mirror (8.4 m telescope), 9.6 deg FOV, 3.2 Gpix camera
located in Chile
Ranked #1 groudn based large project,
Why is LSST good for NEOs? short exposure (15 seconds), rapid cadence (2 sets of 2x15 images per night with colors), smallest object 0.5 AU could detect 10 m object
processing requirements link detections into tracklets, link tracklets into tracks, filter tracks by fitting orbits

PHA completeness: assume H=22 at D=140m
in 10 years, normal cadence, LSST is 80% complete at 140 m
in 12 years, NEO optimized, LSST reached 90% complete at 140 m

For 45 m objects, LSST's warning time would be between 1-3 months

Not a completed telescope, in design and development phase, federal construction funding from NSF/DoE, 2014, first light in late 2017, first engineering light in 2018, full science ops in late 2019, Mountaintop construction started, processing pipelines under construction, federal construction from 2013-2019.

Q: Colors for small objects which are fast rotators may not be able to occur
A: Colors perhaps not from most objects, but perhaps from some objects

Filter strategy for LSST not settled in terms of changing filters between observations, since filters are large

- Daniel Hestroffer
Gaia Astrometry of NEOs

Gaia's basic aim is 3D census of Galaxy, solar system observation
ESA Cornerstone Mission, launch in 2013, 5 year life, scanning low telescope, ES L2 point
scanning - no pointing, sky coverage in 6 months

- Alan Hildebrand
Univ. of Calagary

Dual-use missions funded by CSA and Dept. of National Defense
US-based team members supported by

Micro satellite Systems Canada, formerly Dynacon (currently in Phase D)
launch late in 2011 although PSLV schedule may put in 2012
based on MOST spacecraft

50/50 in time in terms of sat tracking and NEO
initially less than $10M, about $15M now with launch slips
Search for NEOs and ATENs, IEOs (interior Earth Orbit)
Every 2 days will discover NEO

- Paul Abell
"Space-Based BEO Survey Telescope in Support of Human Exploration"

Involved in Hayabusa mission recovery
Human to NEOs is one of the policies of the Obama administration
official policy on June 28, 2010 (Civil Space Guideline #1)
first mission by 2025

NEO Survey telescope suggested by human exploration, science, and planetary defense
Space-based survey telescope is relevant to 2011 Strategic Plan
Asset would be crucial to human exploration
Affordable missions, viable and budget constrained
100 MT launch HLL vehicles, dual launch architecture (cryogenic propulsion stage + CTV + Deep Space Vehicle)
re-entry speed <=11.8 km/s <=180 day round trip (radiation issue) 2025-2030 missions NEOs should be of reasonable size for meaningful human exploration (>30m), large diameters are preferred
Within the current database only 1 known NEO >30m in size suitable for 2025-2030 timeframe (2000 SG344, speculation that it is a rocky body)
Importance of viewing geometry: asteroids close encounter with Earth (<0.1 AU) enables both ground and human exploration capability (accessible and observable)
Looked at NEOs with Earth like orbits, took 20 NEOs with these characteristics, 18/20 NEOS have low DeltaV with short duration missions, for each NEO two types of architecture (min DeltaV and balanced)
Looking at short mission and low DeltaV only one (1) that is larger than 30 m
Where and When to look (2015-2020)
A platform in space is needed to fins

Space-Based telescope, launch ready in 4-5 years, SEL1, trailing Venus, SEL2

NEOCamJPL selected for Discovery Call

Program timeline, 2015-2017 NEO Space Survey,
2019-2022 (robotic precursors)
2022-2025 (human mission planning)
2025 launch mission

Q: are robotic precursor needed, what is the latest thinking
A: First time we send people we send precursor (coming from human safety/EVA people), in-site mission informs safety and prox ops and planetary defense topics, precursor can stay there as ob post and data relay

Rusty: in the process, look at increased flexibility if there is a precursor, opens up space of targets

A: Think there are targets but need a space-based system to get better idea of environment

2011 IAA Planetary Defense Conference: Day 1 Session 1

Notes from Day 1 of 2011 IAA Planetary Defense Conference. Follow twitter feed for more information:

Day 1 (Monday 09 May 2011) Session 1

- Misc introductory remarks by various Romanian dignitaries, including political and scientific representatives

- IAA representative

IAA had Planetary Defense report by Ivan Bekey, keeps referring to asteroids as "rocks", hope to have one more conference in 2 years time

- Dr. Bill Ailor (Aerospace Corporation)

Reflects that this is the most prestigious conference venue for these series of conferences.

- Dr. Richard Tremayne Smith

Previous conferences have been focused on threat, introducing Dr. Anders Sandberg

- Dr. Anders Sandberg

Future of Humanity Institute, Faculty of Philosophy & Oxford Martin School
Oxford University

focuses on human enhancement, also interest in global risks
trying to understand how human species will survive
philosophers good at dealing with new questions and applicable to planetary defense/new global threats
genetic bottlenecks in humanity's history
75K years ago natural disaster reduced human species to around 1000 persons
Black Plague killed more people over time than than alive at start
emergent properties of the internet potential causing problems
past predictions of disasters have been been off by wide variety
problem with risk cognition
risk has an element of outrage in the public's perception
also overestimates probability of various risks
earth impactors relative to other risks are better than other risks
in principal, global coordination may not be required for planetary defense (better but not necessary)
thinking about threat by super-intelligent machines: no research community
use the planetary defense community as an example of how to deal with other threats
scientific search terms: "dung beetle" much more academic references than "human extinction"
weird priorities
reproducible cognitive biases distorting research
availability bias: if one can easily visualize threat than becomes more important
leads to good "story bias" - people expect proper solution will be as dramatic as how impactful story is, people want exciting methods
collective memory counteracts availability bias
"silliness" bias - 10-20 years there was much more of silliness category
"Gambler's" fallacy - if there is an impact than threat goes down
Quantification bias - numbers imply more importance just because of numerical values
If having a heart attack better if only one person than 20 people around, people waiting for others to act
having planetary defense have to act as doctors and break "bystander" effect
"Scope Neglect" willingness to pay goes down as problem becomes larger
"Maybe humanity does not deserve to survive" - as problem becomes larger people become more philosophical
Planetary Defense - under-supplied public good (transgenerational), some other government might do it, costs are visisble but prevention is invisible
Long timescale (paradox of progress, discounting, rational to wait perhaps as world gets more capable, if you believe in exponential increase in technology then perhaps would need to wait, but irrational delays may be an issue
Need a "good enough" solution perhaps
Public is getting globalized, need to get organizations against cognitive biases, planetary defense could be a useful symbol,
Inefficient to build more hospitals: symbol of hope
Planetary defense: collective activity (moral and rational), we care about future generations and that is why we are here

----- Session 1: History and Current Status

- Dave Morrison
"The Asteroid Impact Hazard: Historical Overview"
NASA Lunar Science Institute (NASA Ames)

Assessing the hazard does not mitigate but essential science
Mitigating the hazard - decision makers perspective changed over time, decision makers want to identify and survey objects, SpaceGaurd and others is directed a this point - not a scientific survey per se
Responding to public concern: focusing previously on large global risks but should be worrying about next small one, public and decision makers are pushing into this perspective, directs towards last minute survey for such small impactors

Long term history was protecting earth against comets, because comets thought to be bigger and less information about asteroids, Comets only 1% of risk, look at mitigation first at US and then UK task force in 2000

1949: Raplh Baldwin in 1969 (The Face of the Moon)
1967: Project Icarus (MIT study)
1980: Alvarez KT Mass Extinction

1991: US Congress statement (assess hazard and look at technologies)
1992 workshops including NEO interception workshop (Ed Teller looking at nuclear options)

get multi-kiloton explosion in upper atmosphere

Developing a community to find people interested over the 1990s in planetary defense community and bridge gap of astronomers and DoE community working on mitigation, key meeting in 1993 in Erice, Sicily (40 invitees) to talk to each other and get common interest
1993 meeting that resulted in 1994 book (Hazards Due to Comets and Asteroids)
Spaceguard Survey (1998-present);
any survey will find many more objects smaller than its target population (finds whatever is there)
LINEAR and Catalina have accounted for majority of discoveries
Subtleties from orbits, follow-up of systems needed, difficult time with 1997 XF11 (had error as large as miss distance), made a press release, press coverage, but follow up analysis showed no major impact, compromise with overcome giggle factor and not issuing false alarms, keyholes was an important concept
Developed the Torino and Palermo scale, NEO Eros mission, 2002 Belton mitigation missions
NASA 2003 NASA Science Def. Team

Issues in planetary defense:
Should we develop technology now or wait or should be wait until threat
Should be an international effort
Are nuclear options acceptable, difficult to test
How much should be spend
Who can be trusted with this responsibility
How can we ensure that asteroid defense systems are not misused

Hazard before and after SpaceGuard that hazards are still large objects, sig. risk from objects 200-300 m in diameters.

- Lindley Johnson
Program Executive, NASA NEO Program Status and Plans
coining "Planetary Defense"
counted about 12 different presentations at conference that relate to NASA's NEO program, directly funded by NASA
Since 2009 planetary defense conference
Jan. 2010: US NRC had report
April 2010: New NASA human space flight, human NEO mission by 2025
June 2010: US National Space Policy addressed NEO threat
Apr.-Sept. 2010: NASA Ad. Council Planetary Defense Task Force
Oct. 2010: US OSTP Letter to Congress
FY11/12 NASA Budget Requests: NEEO Program increase to $20.4 M

NASA NEO Search program
LINEAR still operational, Catalina Sky Survey, Pan-STARRS-1, and over the last year NASA WISE
8-10 per month finding large NEOs in heyday, now finding about 1 per month (Large NEOs)
as of 5/1/11 discovered 87-97% of large NEOs, have founded 914 Large NEOs (included 89 Near Earth Comets), 7117 smaller objects found (NEO), about 1000 1 km objects, about 20K at 140 m, about 250K at 50 m

NRC report: cannot meet goal to discover 90% of NEOs 140m or greater by 2020 (cost or performance focused, different options), continue planetary radars, test of kinetic impactor

NEO working group established by UN COPUOS (annual meeting)
Space Situational Awareness Working Group with EU and ESA.

NASA NEO Observaiton Program
90% of objects within 1.3 AU of sun and 140 m in size or larger
Viable targets for future exploration will be found
Continue to fund existing assets and then bring on existing assets

NASA's NEO program $16M increase will:
Extend WISE data
Enable NEO use from USAF Pan-STARRS project
Planetary radar (Arecibo, Goldstone)
Investigate use of ground and space concepts for tracking and characterizing PHOs down to 140m and below
Investigate characterization parameters of NEOs for mitigation studies

Next Gen Survey (still preliminary):
Pan-STARRS from 2 to 4, LSST, SST (DARPA funded telescope at White Sands, 3.6 m primary mirror, ready next Feb., use background images for NEOs), Space-Based Survey Telescope
Space-bases NEOStar concept (as infrared space-based observatory)
Funding for Arecibo through 2011 by NASA until NSF decides how to proceed

2005 YU55 (400 m NEO): good opportunity to do characterization campaign, passes well above the plane of EM system

- Gerhard Drolshagen by ESA (given by Detlef Koshny)
ESA's Space Situational Awareness

Marco Polo-R (asteroid sample return study, 1 out of 4 studies, 2020 launch: Detlef study scientist)

European SSA programme
Surveillance and tracking, space weather, and NEOs
currently in preparatory phase (2009-2011/12) approved (50M Euros for all three programs combined during 2009-2012)
Nominal phase (slices of 4 years over 7 years), preparing for full program to be approved at the end of 2012
EC got interested in topic (younger Alan Harris won proposal)
SSA program: network of sensors, data centers, common data policy, NEO: ESRIN/Italy (NEO data center), in SRR program for ESA-SSA
in the process of setting up a precursor service: based on existing assets (preparation for real program) - bottom up approach
NEOs portion of SSA out of 50M Euros (too complex to state what portion of 50M Euros is NEO-related)
Study by Telespazio/Pisa/INAF Rome produced functional breakdown of future European NEO segment and produced a simulator for testing NEODyd

Basic concept of SSA-NEO Segement (setting up more telescopes, data center, and communication flows to MPC and JPL and other users), existing services get more money

What is SSA-NEO up to?
Contracts for computers, web interaces, governance, telescope analysis/design (finished in 2010: design for optical telescope with 1m effective aperture, 45 square deg FOV, "Fly-Eye Telescope")
Working hard to keep NEO-SSA public (separating telescopes for other SSA needs and NEOs)
regular observations at ESA's Optical Ground Station
Precursor service in ESRIN stated in 01 MArch 2011, operations in Summer 2011
Starting impact effects and deflection strategies, will star this year, producing a snap-shot of knowledge
Study for different orbit propagation algorithms, develop and build a visible-IR camera
building a demo system for space debris and NEO (2 telescopes, one in New Norica and another in AUS)
Update NEO population model (still needs approval)

Set up a precursor service involving key players in Europe
Federate existing assets
After 2013 (full program):
build up a wide survey to detect all objects larger than Tunguska-size objects 3 weeks before their close approach (several 1m 45 deg FOV telescopes)
Set up international program

Q. by Dave Morrison: concerned about specificity on ESA-SSA, what is new?
A: nothing new, but continue what is there but with proper funding (have a few hundred K Euro for proposal), new thing is wide survey that will complement deep survey

Q. by Rusty: relationship between data center and MPC, do you see duplication? Started already to look into possibilities in supporting MPC, do not have funding in current budget, too early to say in the future what happens (goal is not duplicate MPC, goal could be redundancy or additional tasks, do not plan Euro MPC)

- Richard Tremayne Smith
UN COPUOS Action Team Activities

Rationale for UN Involvement
UNISPACE III developed "Action Team" concept to work more directly on issues, UN Action Team 14 on NEOs established and elevated to WG status in 2007 within COPUOS S&T, approved work plan until at least 2012

Past models: IADC (Inter0agency Debris Comm.) - certain parties tried to get that body into looking into NEOs (but not successful), UN developed own space debris guidelines, used ASE panel in similar manner to accelerate process of NEO measures

ASE recommendations: Document no evolving within the UN system with ownership of delegations (through AT 14 report at UN COPUOS)

CRP reflects three elements of ASE Report (IAWN, MPOG - IADC analogue, MAOG - role for UN body)
Who has role for MAOG: UN OOSA, ISDR, WMO (7x24 network, for $1M extra could do NEO work) potentially, UN Sec. Council, Another UN body?, non UN bodies?

- Alan Harris (The European)
"A Global Approach to NEO Impact Threat Mitigation"

An EC funded program on NEOs,
Another organization that is planning to make money available, this is the EU through its EC and its FP7 research program, given initially a poster slot, look as this will be funded, more significant, NEOShield Proposal - submitted in response to FP7 research proposals (26 Nob. 2010, 13 members), topped one of 6 proposals, 5.5 M Euro (Funds provided by EU: 4.0 M Euro), anticipated kick-off of Nov./Dec. 2011 (duration 3.5 years), will investigation: gravity tractor, kinetic impactors, and blast deflection

1. Science: including lab experiments, mitigation precursor recon, using asteroid surface analog materials, numerical simulations,
2. Mitigation Demo Mission: identify suitable mission targets, design a missions
3. Global response campaign roadmap

international team including Astrium, Deimos Space, Surrey, D. Morrison
Univ. of Surrey will work with D. Morrison on gravity tractors

Follow Twitter Feed for Latest Updates on 2011 IAA Planetary Defense Conference

I shall attempt to tweet from the 2011 IAA Planetary Defense Conference.

Twitter Feed: ac_charania

01 May 2011

An interesting minor link between The Prisoner TV series and Planetary Defense

How The Prisoner TV series and planetary defense are related.

According to this video, Donald Tosh (who was a script editor for Doctor Who), met Prisoner script editor George Markstein. Those discussions led to a script proposal by Tosh in which No. 6 (The Prisoner) meets French aviator Antoine de Saint-Exupéry' in the Village (a prisoner himself). De Saint-Exupéry' is the author of The Little Prince, who lives on an asteroid called B-612. The B-612 Foundation is a non-profit foundation organized to work for planetary defense issues.

The following video is Tosh talking about his script discussions with Markstein.

Link: YouTube Video ("THE PRISONER. Unused script.")

AsteroidAware project and video

AsteroidAware seems to have posted a YouTube Video. Here is more information on this project from their website:

The 2007 Planetary Defense Conference recommends “to provide or enhance Internet sites to show how threats evolve and to illustrate possible action scenarios”. Thereby, establishment of informational and communicational AsteroidAware web-site with the exact, authentic data about the past and the present of Earth's impact events will assist in achievement of positive results and progress in different directions on political, international, social and scientific levels. In the long perspective it can become a central resource of the future global organization of planetary defense that will be responsible for the worldwide warnings and protection actions to advance the international cooperation. Information, social and knowledge-based environments of the web-source should educate governmental officials and the public on the nature of the NEO threats and expectations on NEO detections and warnings. The direct communication between the scientists and policy makers through the AsteroidAware web-site network should increase public awareness and trust. That will also be helpful for international scientific organizations in exchange of research data and forthcoming events. Finally it's necessary to note that after 20-30 years when the probable threat can overtake the planet, the Internet possibly will be one of the main information resources in the world.

For more information on Asteroid Aware contact (from their website):

Denis A. Usikov
The Institute of Europe of the Russian Academy of Sciences (IE RAS),
M.V. Lomonosov MSU Faculty of World Politics Alumni Association
+7 (910) 430 71 21

Link: Asteroid Awareness website

Link: YouTube Video ("Asteroid Awareness")

B612 Foundation Asteroid Deflection Visualizations

Link: YouTube Video ("B612 Foundation Asteroid Deflection Visualization: Kinetic Impactor Impact")

Link: YouTube Video ("B612 Foundation Asteroid Deflection Visualization: Gravity Tractor Close-up")

Link: YouTube Video ("B612 Foundation Asteroid Deflection Visualization: Orbit Determination Phase")

Link: YouTube Video ("B612 Foundation Asteroid Deflection Visualization: Gravity Tractor Phase")

Link: YouTube Video ("B612 Foundation Asteroid Deflection Visualization: Earth miss after 10 years")

Link: YouTube Video ("B612 Foundation Asteroid Deflection Visualization: Asteroid Close-up")

YouTube Video:"Rusty Schweickart - Deflecting an Asteroid" (17 November 2010)

Link: YouTube Video ("Rusty Schweickart - Deflecting an Asteroid")

YouTube Video:"Rusty Schweickart, The Asteroid Threat Over the Next 100,000 Years"

Link: YouTube Video ("Rusty Schweickart, The Asteroid Threat Over the Next 100,000 Years, SALT tak")

Radio Interview on Planetary Defense: U.S. Rep. Dana Rohrabacher and Dr. Michael J. Drake

A recent radio episode on the Frank Morrison show (20 April 2011) on 89.3 FM KPCC entitled “Deep Impact,” but with an unhappy ending: Who will watch for Earth-bound asteroids in an era of budget cuts?". The guests included Rep. Dana Rohrabacher (R-California’s 46th District, Costa Mesa, Huntington Beach; chairman of the Oversight & Investigation Subcommittee of the House Foreign Affairs Committee) and Michael J. Drake (director, Lunar and Planetary Laboratory, University of Arizona).

Link: 89.3 FM KPCC Episode: Patt Morrison show for April 20, 2011 [.mp3 of show]

Link: 89.3 FM KPCC Episode: Patt Morrison show for April 20, 2011 (“Deep Impact,” but with an unhappy ending: Who will watch for Earth-bound asteroids in an era of budget cuts)

New Yorker Article: "Vermin of the Sky: Who will keep the planet safe from asteroids?"

Jaime Hernandez Illustration in The New Yorker.

An article from the New Yorker (from February 2011) on planetary defense.

"Vermin of the Sky: Who will keep the planet safe from asteroids?"
Tad Friend
FEBRUARY 28, 2011

Link: New Yorker Article

NASA's Lindley Johnson speaking at Gartner's Security & Risk Management Summit (20-23 June 2011)

NASA's Lindley Johnson speaking to a non-aerospace audiance on planetary defense at the Gartner Security & Risk Management Summit, 20-23 June 2011 at National Harbor, MD USA. Here is the session information:

Preparing for Planetary Defense
Thursday, 23 June 2011
10:20 AM-11:20 AM
Speaker: Col. Lindley Johnson
Session Type: Keynote Session

Preparing for Planetary Defense: What if an asteroid was headed for impact of the Earth? How would we know? Would we want to know? Could anything be done to prevent such a catastrophe? Hollywood disaster movies have provided entertaining depictions of mankind struggling to avoid such devastation, but what’s the real story? Lindley Johnson from NASA’s Planetary Science Division heads the nation’s actual efforts to detect such hazards in sufficient time to potentially take actions to prevent the disaster. Find out how real the threat is and what can be done to mitigate it. This is the ultimate scenario in planetary security and risk management.

Link: Gartner Security and Risk Conference Talk Website
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