Article: What to Do Before The Asteroid Strikes

Good summary article, selections from the article...

Because Apophis was discovered during one of the world’s greatest natural disasters, the worries about the impact went largely unnoticed. But that tense day, December 26, 2004, stunned the small group of astronomers who dutifully detect and plot trajectories of hundreds of thousands of the millions of chunks of rock whizzing around the solar system. Though too small to end civilization—unlike the asteroid that may have doomed the dinosaurs—Apophis could pack a punch comparable to a large nuclear weapon. Traveling at 28,000 miles per hour, it would heat up as it passed through Earth’s atmosphere, turning the dark rock into a fiery sun as it arced across the sky. Then it would either explode just aboveground—as one most likely did in 1908, leveling a vast forest in the Tunguska region of Siberia—or gouge a crater 20 times its size. “If it hit London, there would be no London,” says Apollo 9 astronaut Rusty Schweickart, who had closely followed the discussion of the potential 2029 impact. Slamming into the ocean, Apophis could create a tsunami dwarfing the one that killed more than 200,000 people around Indonesia.

Schweickart was deeply shaken by the Apophis experience. “I don’t know how to transmit to you the emotion, the level of intensity of a group of people you could name on two hands during those days in December 2004,” he says. His interest in the asteroid threat extended back to 2001, when he and a few colleagues sat down at NASA’s Johnson Space Center in Houston just six weeks after the terrorist attacks on New York and Washington to discuss ways to deflect an incoming asteroid.

"What to Do Before The Asteroid Strikes: The doomsday rock is out there. It’s just a matter of time..."
Andrew Lawler
01 November 2007
Discover Magazine

Link: Article (Discover Magazine)

What is a Screw Rocket and how can I use it to move an asteroid?

I ran across this recent paper on the use of screw-rockets for asteroid deflection. Screw rockets seem similar to nuclear powered mass deflection, which is a concept that SEI has examined, notably of multiple mass drivers. Interesting that it was submitted for the Chinese Journal of Astronomy and Astrophysics. Note: The SEI MADMEN concept is not referenced in the paper.

Reference:
Asteroid Deflection: How, where and when?
Authors: D. Fargion
(Submitted on 12 May 2007 (v1), last revised 3 Sep 2007 (this version, v3))
Chin. J. Astron. Astrophys. Vol. 0, No. 0, (200x) 000–000
Chinese Journal of Astronomy and Astrophysics

Abstract:
To deflect impact-trajectory of massive km^3 and spinning asteroid by a few terrestrial radius one need a large momentum exchange. The dragging of huge spinning bodies in space by external engine seems difficult or impossible. Our solution is based on the landing of multi screw-rockets, powered by mini-nuclear engines, on the body, that dig a small fraction of the soil surface, to use as an exhaust propeller, ejecting it vertically in phase among themselves. Such a mass ejection increases the momentum exchange, their number redundancy guarantees the stability of the system. The slow landing (below 40 cm s^-1) of each engine-unity at those lowest gravity field, may be achieved by save rolling and bouncing along the surface. The engine array tuned activity, overcomes the asteroid angular velocity. Coherent turning of the jet heads increases the deflection efficiency. A procession along its surface may compensate at best the asteroid spin. A small skin-mass (about 2 10^4 tons) may be ejected by mini nuclear engines. Such prototypes may also build first save galleries for humans on the Moon. Conclusive deflecting tests might be performed on remote asteroids. The incoming asteroid 99942 Apophis (just 2% of km^3) may be deflected safely a few Earth radius. How to tag its trajectory is described. Its encounter maybe not just a hazard but an opportunity, learning how to land, dig, build and also to nest save human station inside. Asteroids amplified deflections by gravity swing maybe driven into longest planetary journeys.

Link: Abstract

Link: PDF of Paper

Link: SpaceWorks Engineering, Inc. (SEI) paper on multiple mass drivers for asteroid deflection (from the 2007 Planetary Defense Conference)

Link: SpaceWorks Engineering, Inc. (SEI) presentation on multiple mass drivers for asteroid deflection (from the 2007 Planetary Defense Conference)

Debunking Asteroid Impact Fears

"Asteroid 1999 AN10 is predicted to come close to Earth in 2027 and 2039. NASA doesn’t think that it will hit. However there is evidence that it will - from the Bible."

Really? Well BadAstronomy takes the claims from the Asteroid2039.com website and examines them in further depth.

Link: BadAstronomy Article

Popular Science Article on Human Missions to NEOs

From the article...

Here we are, nearly eight years into the 21st century, and the most spectacular manned mission NASA can pull off is a trip to the International Space Station, a mere 210 miles above the Earth. Even the most ambitious part of NASA's current plans for human spaceflight involves visiting a celestial body we've already been to: the moon. Astronauts, space buffs and an unimpressed public hunger for space exploration that's more dramatic, more heroic, more new. Something like, say, landing astronauts on a distant rock hurtling through space at 15 miles per second.

"NASA's New Target: A manned mission to an asteroid sounds far-fetched, but a new study says it will soon be possible"
Dawn Stover
October 2007
Popular Science

Link: Article

New Apophis Analysis: Predicting Apophis' Earth Encounters in 2029 and 2036

From the article:

Researchers at NASA/JPL, Caltech, and Arecibo Observatory have released the results of radar observations of the potentially hazardous asteroid 99942 Apophis, along with an in-depth analysis of its motion. The research will affect how and when scientists measure, predict, or consider modifying the asteroid's motion. The paper has been accepted for publication in the science journal "Icarus" and was presented at the AAS/DPS conference in Orlando, Florida in October of 2007.

The analysis of Apophis previews situations likely to be encountered with NEAs yet to be discovered: a close approach that is not dangerous (like Apophis in 2029) nonetheless close enough to obscure the proximity and the danger of a later approach (like Apophis in 2036) by amplifying trajectory prediction uncertainties caused by difficult-to-observe physical characteristics interacting with solar radiation as well as other factors.

Link: Paper

Link: JPL NEO Site Article

NEO News (10/25/07) Amazing Comet Holmes

Note: The following is the 10/25/07 Edition of NEO News, an email newsletter distributed by David Morrison.

NEO News (10/25/07) Amazing Comet Holmes

This is a special note to alert you to something you may want to see, especially if you have access to a small telescope.

Approximately 36 hours ago Comet Holmes (a normally inconspicuous Jupiter-family comet with aphelion at the orbit of Jupiter and perihelion at 2.2 AU) brightened by almost a million-fold. This is equivalent to the planet Saturn suddenly becoming as bright as the full moon. On October 23-24, Comet Holmes went from magnitude 17 to magnitude 2.8 in just a few hours, doubling in brightness every half hour. At its discovery in 1892, this comet also underwent a similar sudden brightening, presumably due to a very large ejection of gas and dust.

The comet is now easily visible to the naked eye as a bright yellow "star" in the constellation Perseus. For northern hemisphere observers, it can be seen almost all night, passing nearly overhead. A good source for the latest information is the Sky & Telescope webpage http://www.skyandtelescope.com/observing/home/10775326.html or at http://www.aerith.net/comet/catalog/0017P/2007.html. The best finding chart I have seen is on the Netherlands webpage http://www.shopplaza.nl/astro/.

I looked at the comet about midnight last night from the balcony of my urban townhouse. It was about magnitude three, and at low telescopic power it was conspicuous as a bright yellowish disk, looking almost like a planet. At moderate power the disk resolved into a very bright inner coma and a slightly asymmetric fainter outer cloud, but no tail was visible. I have never before seen anything like it.

David Morrison
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NEO News (now in its thirteenth year of distribution) is an informal compilation of news and opinion dealing with Near Earth Objects (NEOs) and their impacts. These opinions are the responsibility of the individual authors and do not represent the positions of NASA, the International Astronomical Union, or any other organization. To subscribe (or unsubscribe) contact dmorrison@arc.nasa.gov. For additional information, please see the website http://impact.arc.nasa.gov. If anyone wishes to copy or redistribute original material from these notes, fully or in part, please include this disclaimer.

NEO News (10/23/07) Marco Polo, Dawn, Workshop, Congress, DPS

Note: The following is the 10/23/07 Edition of NEO News, an email newsletter distributed by David Morrison.

NEO News (10/23/07) Marco Polo, Dawn, Workshop, Congress, DPS

ESA ANNOUNCES MARCO POLO SELECTION (October 21, 2007)

The European Space Agency has announced the results of its Cosmic Visions 2015-2025 call for proposals. Fifty space science missions for the next decade were proposed, with just seven selected. They range from X-ray and far-infrared observatories to planet finders and a near-earth asteroid sample return mission. These seven, together with the LISA gravitational wave observatory, will go ahead for further study in the next few years, and then two will be chosen for launch in 2015-2017. The asteroid mission, called Marco Polo, is a sample-return mission to a near-Earth object (NEO), Marco Polo would characterize a NEO at multiple scales and return a sample. If approved, the mission would study the origins and evolution of the Solar System, the role of minor bodies in the process, origins and evolution of Earth and of life itself. It would consist of a mother satellite which would carry a lander, sampling devices, reentry capsule as well as instruments. If approved, the mission would be implemented in collaboration with JAXA (perhaps combined with the Hayabusa Mark 2).

The ESA NEA mission Don Quijote, which has been studied for several years as a technology demonstration, is shifting to an orbiter mission called SANCHO, with Spain taking the lead in its development. It might be possible later, however, to restore the small surface package and/or the high-speed impactor originally proposed for Don Quijote through partnerships with other space agencies.


DAWN IS ON THE WAY TO VESTA AND CERES

The Dawn spacecraft successfully launched at 7:34 am EDT on September 27, 2007. On October 9, it successfully tested its ion propulsion system. With its solar electric propulsion operating, Dawn is set to travel over the next 8 years to Vesta and Ceres, the two largest maIn belt asteroids, orbiting each asteroid. Dawn is a NASA Discovery mission, with Chris Russell of UCLA as PI and JPL as managing NASA Center.

Dawn will begin its exploration of asteroid Vesta in 2011 and the dwarf planet Ceres in 2015. These two icons of the asteroid belt have been witness to much of our solar system's history. By utilizing the same set of instruments at two separate destinations, scientists can more accurately formulate comparisons and contrasts. Dawn's science instrument suite will measure shape, surface topography, tectonic history, elemental and mineral composition, and will seek out water-bearing minerals. In addition, the Dawn spacecraft itself and how it orbits both Vesta and Ceres will be used to measure the celestial bodies' masses and gravity fields.

Since Vesta and Ceres are not NEAs, we will not be covering this mission in any detail in NEO News. For regular updates, please check the Dawn homepage at (www.nasa.gov/mission_pages/news/dawn)


WORKSHOP AT NASA AMES ON LOW-COST MISSIONS TO NEOS

Summary from David Morrison, 22 October 2007

The past weekend (October 20-21) more than 40 NEO scientists and engineers met for informal discussions of the potential of low cost missions to characterize NEOs. This workshop was part of series of informal weekend workshops hosted by Ames Center Director Pete Worden. The organizers were David Morrison (Senior Scientist, NASA Astrobiology Institute) and Stephanie Langhoff (Ames Chief Scientist), assisted by Organizing Committee members Erik Asphaug, Dan Durda, Bob Farquhar, and Pete Klupar. The workshop agenda was structured to bring together science and engineering communities who have a common interest in small missions but rarely talk to each other.

The workshop agenda blended three major themes: (1) The importance of characterizing small NEOs and the kinds of science measurements that need to be made. (2) How to get to the targets: populations, orbital dynamics, direct vs. gravity-assist trajectories, opportunities for secondary payloads and missions of opportunity. (3) Low-cost missions: spacecraft, instruments, proximity operations, propulsion, landers, and impactors. Fifteen-minute papers covered the above topics, with plenty of time for discussion. The final afternoon was devoted to interactive discussions, organized around three key questions that the workshop participants could explore in smaller breakout sessions, on (1) impactors, (2) rendezvous and orbiter missions, and (3) landers. Sample return was considered outside the possible range for small missions, defined here as those costing under $100M.

The workshop consensus was that small (low cost) missions to NEOs make sense. Since a major objective is to sample the diversity of this population, multiple small missions are cost-effective. At this stage of our knowledge, we can select the most accessible targets, which can be reached with modest launch vehicles, or in many cases as secondary payloads or missions of opportunity. The most powerful general exploration approach is with orbiting or rendezvous spacecraft. Impactors used in cooperation with other missions are potentially able to explore interior structure, and it may also be possible to achieve simple landings within the "small mission" cost cap. In all these cases, a program of NEO missions can be developed using either secondary payload opportunities or Minotaur-class launch vehicles, so long as we select the targets (as opposed to the asteroids selecting us).


CONGRESSIONAL HEARING RESCHEDULED TO NOVEMBER 8

The Congressional hearing on NEO surveys (originally planned for October 11) has been rescheduled for November 8. The hearing before the House Subcommittee on Space and Aeronautics will tentatively include the following witnesses: Jim Green (NASA HQ), Scott Pace (NASA HQ), Don Yeomans (JPL), Rusty Schweickart (B612), Don Campbell (Cornell/Arecibo), and Tony Tyson (LSST). Further information including opportunities to listen on-line will be found at the Committee website (http://science.house.gov/).


NEOS AT DPS MEETING

The 2007 meeting of the Division for Planetary Science of the American Astronomical Society was held in Orlando October 7-12, with about 800 planetary scientists attending. Asteroids and comets were remarkably prominent at this annual meeting. Not counting the Kuiper Belt, the program lists 171 papers (oral and poster) on comets and asteroids, rather evenly distributed among NEOs, Main Belt Asteroids, and Comets. Also, 10 out of 35 oral sessions were on comets and asteroids. These included two "special sessions" on the first day of the meeting dealing with NEAs: "What's next with NEO searches" and "YORP Observed!".

The session on "NEO Searches" was organized by Lindley Johnson (NASA HQ) and Don Yeomans (JPL). The program was:
- Lindley Johnson: The state and future of NASA's NEO program
- Robert Jedicke: The Pan-STARRS PS1 survey
- Steven Chesley: Asteroid impact monitoring: Status and predictions
- Paul Abell et al.: Piloted Missions to NEOs via the CEV
- Donald Yeomans: NEO Lessons Learned
- Steven Larson et al.: Current ground-based surveys for NEOs
- Edward Wright: Space infrared observations of NEOs
- Zelljko Ivezic: LSST's NEO survey capabilities
- David Morrison: Role of NEO characterization missions

The YORP (the Yarkovsky-O'Keefe-Radzievskii-Paddack) effect is a torque that can modify the rotation rates and axial tilt of small bodies via the combined effects of incident solar radiation pressure and the recoil effect from non-isotropic thermal radiation from the object. This effect can be seen in the alignments of spin vectors for members of asteroid families, and it is emerging as an important effect for spinning up asteroids to create binaries and for the long-terms evolution of asteroid orbits. While the YORP effect has been discussed theoretically for many decades, it had not been observed directly. The first clear detection is from optical monitoring of NEA 2000PH5, which has recently been given the name 54509 YORP. The Japanese Hayabusa mission has also observed this change in spin for the small NEA Itokawa.

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NEO News (now in its thirteenth year of distribution) is an informal compilation of news and opinion dealing with Near Earth Objects (NEOs) and their impacts. These opinions are the responsibility of the individual authors and do not represent the positions of NASA, the International Astronomical Union, or any other organization. To subscribe (or unsubscribe) contact dmorrison@arc.nasa.gov. For additional information, please see the website http://impact.arc.nasa.gov. If anyone wishes to copy or redistribute original material from these notes, fully or in part, please include this disclaimer.

Estimate at Submissions for Planetary Society 2007 Apophis Mission Design Competition

Here is my estimate for those teams that have submitted to the 2007 Planetary Society Apophis Mission Design Competition. About 100 teams sent letters of intent and I believe only 30 or so teams actually submitted final written proposals. Here is my list (in no order):

1. SpaceWorks Engineering, Inc. (SEI) and SpaceDev, Inc. team
Link: News Item of Foresigh Spacecraft Design (note: I was on this team)

2. Astrium:
Link: News Article from BBC

3. Georgia Institute of Technology

4. University of Michigan
Link: Class Website

5. MIT
Students: Thomas Coffee, Wilfried Hofstetter, Ryan McLinko, Chase Million; Reviewer / advisor: Paul Wooster
Link: Project Site

6. xrd1 Consulting (I do not know if this is a company or person, I believe they/him are located in Michigan and run a blog called “Homeland Currency Security”)
Link: HTML Version of Report

7. Vu Trong Thu (Personal)
Link: Personal proposal

- [Not known to be an entry] Interesting paper from Regan Howard and Ross Gillett entitled: "A Low Cost Rendezvous Mission to 99942 Apophis" from Orbital Science Corporation (OSC), Space Systems Group (not confirmed as a submission, but interesting paper).
Link: IEEE Xplore reference

ESA Mission Update: Marco Polo - an asteroid sample-return mission

This an update on the European Space Agency (ESA) proposed Marco Polo mission.

Selections from the article:

A clearer idea of Europe's next destinations in space emerged at a meeting of the European Space Agency (ESA) Space Science Advisory Committee on 17 and 18 October. A number of candidates for future missions were selected...From a list of 50 proposals submitted by the scientific community [one of the mission selected was the following:]

Marco Polo would characterise a near-Earth object at multiple scales and return a sample. This could provide new information on the evolution of the Solar System, the role of minor bodies in the process, the origins and evolution of Earth and of life itself. This mission would also be implemented in collaboration with JAXA.

All of the above missions will now compete in an assessment cycle, due to end in 2011. This will result in the selection of two missions for implementation, with launches in 2017 and 2018.

Link: Article: ESA

Book Update: Planetary Defense and Asteroids/Comets

Catastrophic Events Caused by Cosmic Objects (Hardcover)
by V.V Adushkin (Editor), I.V. Nemchinov (Editor)

Link: Amazon.com

Rosetta: Mission to Comet 67P/Churyumov-Gerasimenko (Hardcover)
by C.T. Russell (Editor)

Link: Amazon.com

Surviving Armageddon: Solutions for a Threatened Planet (Paperback)
by Bill McGuire (Author)

Link: Amazon.com