[tt] [x-risk] 1-in-45, 000 odds asteroid Apophis-99942 on rendevous with Earth in 2029

[Eugen Leitl]

----- Forwarded message from "Hughes, James J." <James.Hughes at trincoll.edu> -----

From: "Hughes, James J." <James.Hughes at trincoll.edu>
Date: Thu, 24 May 2007 13:38:39 -0400
To: For discussion of existential risks <existential at transhumanism.org>
Subject: [x-risk] 1-in-45,
	000 odds asteroid Apophis-99942 on rendevous with Earth in 2029
Reply-To: For discussion of existential risks <existential at transhumanism.org>


Planetary Society's Apophis Mission Design Competition
http://www.planetary.org/programs/projects/apophis_competition/


http://www.satnews.com/stories2007/4505/

Monster Asteroid to Hit the Earth in 2036 Spawns Earth Rescue Ideas

MOSCOW, May 24, 2007 - Satnews Daily - In February 2006, the Russians
reminded everyone that an asteroid should shave by the Earth in April
2029, a scant 22 years away.

At its worst, the asteroid-identified as Apofiz-99942-should smash into
the Earth by 2036. At the least, it should wipe out practically all
civilian and military satellites in geostationary orbit, which is about
42,000km above the planet.

Russia's Pulkovo Space Observatory estimates that on April 13, 2029,
Apofiz-99942 (the inverted three 6s are not lost on the superstitious)
will be at its closest distance to the Earth for 200 years. Apofiz
(spelled Apophis in the West) will pass the Earth at a distance of
30,000 to 40,000 km. Whatever happens, the Earth will suffer from the
effects of the close encounter with this asteroid.

According to Russia's Institute of Applied Astronomy, about 400
asteroids and over 30 comets currently present a potential threat to the
planet.

This chilling doomsday scenario wrought by the "killer asteroid"
Apofiz-99942 has prompted the California-based non-governmental group,
The Planetary Society, to launch the "Apophis Mission Design
Competition".

The Planetary Society is the largest space interest group in the world.
Carl Sagan, Bruce Murray and Louis Friedman founded The Planetary
Society in 1980.

The Apophis Mission Design Competition is offering $50,000 in prize
money for designing a mission to rendezvous with and "tag"
Apophis-99942. The society has reported that more than 100 teams and
individuals from 25 nations are developing plans that could save Earth
from Apophis.

Tagging may be necessary to track Apophis accurately enough to determine
whether it will impact Earth, and thus help decide whether to mount a
deflection mission to alter its orbit.

Apophis is a Near Earth object (NEO) some 400 meters in size. If Apophis
passes through a several hundred-meter wide "keyhole" in 2029, it will
impact Earth in 2036. While current estimates rate the probability of
impact as very low, Apophis is being used as an example to enable design
of a broader type of mission to any potentially dangerous asteroid.

Very precise tracking may be needed to determine the probability of a
collision. Such precise tracking could require "tagging" the asteroid,
perhaps with a beacon, transponder, reflector -- or some other method.
Exactly how an asteroid could best be tagged is not yet known, nor is it
obvious.

The recent Planetary Defense conference, a gathering of experts in all
aspects of NEOs, recommended that results from this (Planetary Society)
competition should be studied as a first step for future considerations
of tagging. This competition may be a model for encouraging creative
ideas for other aspects of planetary defense.

NASA currently has no plans to study methods of asteroid deflection, or
how to tag an asteroid for precise tracking. NASA and the European Space
Agency (ESA) have co-sponsored the society competition and will study
the best mission designs offered.

Russia, however, has said it is prepared to repel asteroids to save the
Earth. Viktor Remishevsky, deputy head of the Russian Federal Space
Agency (Roscosmos) was reported to have said that if necessary, Russia's
rocket-manufacturing complex can create the means in space to repulse
asteroids threatening Earth. He also noted that saving the Earth from
the threat of asteroids demands international cooperation.

In addition to NASA and ESA, The Planetary Society is conducting this
competition in cooperation with the Association of Space Explorers
(ASE), the American Institute of Aeronautics and Astronautics (AIAA),
and the Universities Space Research Association (USRA). The society will
present the winning entries to the world's major space agencies, and the
findings of the competition will be presented at relevant scientific and
engineering conferences.

The United States, United Kingdom, Italy, India, Spain, Russia and
Germany are the nations with the highest number of notices of intent
submissions, said the society. The deadline for mission design proposals
is August 31, 2007.

"We are thrilled that out Apophis Mission Design competition has
generated such an enthusiastic response from around the world and look
forward to seeing creative thinking on how to tag an asteroid," said
Bruce Betts, The Planetary Society's director of projects. 

http://www.space.com/news/051103_asteroid_apophis.html

Asteroid Apophis: Dealing with Earth's Future Troublemaker
By Leonard David

Senior Space Writer

posted: 3 November 2005
9:58 a.m. ET

BOULDER, Colorado - The potential for a newly discovered asteroid
smacking into the Earth in 2036 cannot be discounted. NASA has sketched
out a response strategy in the outside possibility that the space rock
becomes a true threat.

NASA's action plan was the result of prodding by a group of astronauts,
scientists and other technical specialists uneasy about the current lack
of action to protect the Earth from the impact of near Earth objects
(NEOs).

The object was found last year through the efforts of NASA's Spaceguard
Survey. In 1998 NASA formally initiated the Spaceguard Survey by
adopting the objective of finding 90 percent of the near Earth asteroids
larger than 3,280 feet (one kilometer) diameter within the next decade -
before the end of 2008.

Asteroid 99942 Apophis - first labeled as 2004 MN4 -- is estimated to be
roughly 1,000 feet (320 meters) in diameter. Were it to strike Earth, it
would not set off global havoc but would generate significant local or
regional damage, experts say.

Worrisome to asteroid watchers is the exceptionally close flyby of Earth
by Apophis on April 13, 2029. So close in fact, the space rock will be
naked-eye visible as it darts by. And what can't be ruled out at this
time is that Apophis may pass through a gravitational "keyhole" - a spot
that alters the asteroid's trajectory as it zips by our planet and might
put it on the bee-line lane for banging into Earth seven years later.

Issue of critical importance

Concern over asteroid Apophis and the ability to precisely chart its
trajectory -- and take steps if needed to deflect the object -- were
fervently voiced by the B612 Foundation, chaired by Russell Schweickart,
a former Apollo astronaut.

The group requested that NASA carry out an analysis that included the
possibility of placing an active radio transponder on the object. Doing
so at a fairly early date would yield the requisite orbital accuracy of
the asteroid as it sped through space.

In a June 6 letter to NASA Administrator, Michael Griffin, Schweickart
on behalf of the B612 Foundation called for support in "resolving an
issue of critical importance" - namely whether a scientific mission
should be launched to asteroid Apophis in the near term.

Such a probe, if dispatched, Schweickart stated, would provide knowledge
of the asteroid's orbit in time to initiate a deflection mission in the
unlikely event one should be required. The position of the B612
Foundation was that the mission should be staged, pointing out that
NASA's NEO program personnel apparently did not concur with that view. A
spacecraft mission to Apophis would augment tracking of the object from
the ground, the letter to Griffin explained, and also carry out a number
of scientific duties too.

NASA response

NASA provided a formal response to the B612 Foundation's June communiqu
via an October 12 letter from Mary Cleave, Associate Administrator for
Science Mission Directorate.

That NASA reply came with an appended detailed analysis by Steven
Chesley of NASA'S NEO Program Office at the Jet Propulsion Laboratory
(JPL) in Pasadena, California. The study by Chesley dug into Apophis'
orbit, under varying conditions, and contained other items pertaining to
the space agency's findings about the Apophis matter.

"The key conclusion to be taken from this analysis," Cleave explained in
the letter, "is that aggressive (i.e., more expensive) action can
reasonably be delayed until after the 2013 observing opportunity. For
Apophis, the 16 years available after 2013 are sufficient to recognize
and respond to any hazard that still exists after that time."

Cleave noted in the letter that while Apophis "is an object whose motion
we will continue to monitor closely in the coming years, we conclude a
space mission to this object based solely on any perceived collision
hazard is not warranted at this time."

Not ruled out by Cleave, however, is the prospect of Discovery-class,
low-cost missions sent to Apophis, "based on purely scientific
arguments," she said.

"Indeed, the asteroid's orbit is particularly attractive for spacecraft
rendezvous, and the extraordinary close encounter in April 2029 provides
a unique opportunity to investigate a number of scientific NEO issues,"
Cleave explained in the letter.

Pinpointing the object's whereabouts

While Schweickart said that the NASA response to the B612 Foundation's
concern is a step forward, there are other issues still to be resolved.

One matter involves radar tracking of Apophis.

On one hand, radar plays a crucial role in being able to rationally
determine the future likelihood of a NEO impact and potentially in
planning for a deflection mission when required.

Yet the availability of NEO radar tracking, and the budgets to support
this work in the future is highly uncertain, even precarious,
Schweickart and the B612 Foundation emphasize. Radar hits of Apophis at
each opportunity through 2021 are important to keep watch of the
object's whereabouts.

"Tracking these asteroids once you know they exist and pinning down
their orbits is really not science," Schweickart told SPACE.com. "This
is public safety. It's disaster preparedness."

Begging time and bumming bucks

When Apophis swings by Earth, Schweickart said the asteroid will likely
change its orbit. Also, its spin characteristics may be altered. Due to
Earth's gravity tugging on the object, "asteroid quakes" could reshape
Apophis, he said.

Moreover, still far from resolution is a "who's in charge" proclamation
about troublemaking NEOs, Schweickart said.

"It would be great if we had NASA doing this as a regular process.
Unfortunately, the mindset that's essentially required by their budget
is to think about discovery, not to think about the potential need for
deflection," Schweickart added. "Until your mindset is oriented that
way, you're going to miss things."

Until an agency is identified that is responsible for all of this,
Schweickart cautioned, everybody is "begging time and bumming bucks"
from some other program. "This whole thing is sort of in a precarious
position until somebody gets around to assigning agency responsibility,"
he said.

Japan's Hayabusa mission

Regarding the skill required to deposit a transponder on Apophis,
Schweickart saluted Japan's Hayabusa asteroid sample-return mission, now
in progress.

That craft is scheduled to make two landings on its target asteroid -
Itokawa -- later this month. The mission is geared to haul back samples
of the object to Earth.

Scientists at Japan's Institute of Space and Astronautical Science
(ISAS) are working day-by-day issues in readying the probe for contact
with the asteroid, including release of a mini-robot onto Itokawa that
will move about and survey its rocky surroundings. ISAS is a research
arm of the Japan Aerospace Exploration Agency (JAXA).

"It's an impressive mission," Schweickart said, sure to yield
operational experience and lessons learned on how best to execute duties
on asteroid Apophis.

Global preparedness

The ruin stemming from asteroid Apophis colliding with Earth would
potentially be very great.

Indeed, the consequences, Schweickart suggested, would dwarf those seen
as a result of the Indian Ocean tsunami in December 2004, hurricanes
Katrina and Rita in September of this year, and the Pakistan earthquake
last month.

In regards to global preparedness in handling these unusually
devastating events of late, "it's basically out of sight...out of mind,"
Schweickart said. "That's the real challenge for society. The things
that you don't know about are one thing. But the things that you do know
about, and don't do something about...those are the ones that are really
tough."

Refine the impact probability

Fully concurring with NASA's response is Alan Harris, a senior research
scientist and asteroid expert for the Space Science Institute
headquartered here.

Harris noted, as has been underscored by the B612 Foundation, that if
Apophis is indeed on an impact trajectory, then ground-based radar
observations will not be able to refine the impact probability to
greater than 20 percent. "That is, we would still not know better than
one-chance-in-five whether the impact would really occur or not," he
told SPACE.com. 

"We really would need a transponder to improve tracking enough to firmly
establish that an impact would occur," Harris said.

What has been overlooked, or at best under-emphasized, Harris added, is
a point raised in the NASA response. Ground-only tracking has a 99.8
percent chance of eliminating any chance at all of an impact. Thus,
there is only one-chance-in-500 that ground-based tracking will fail to
resolve the issue in favor of no impact. "For this reason I think the
NASA conclusion is entirely sensible," he said.

Wait and see strategy

Harris said that there are Apophis observing opportunities every 6-8
years, with each one having about a 90 percent chance of eliminating any
possible impact. At each of these "shoulder" times, he said, one can
re-evaluate the "wait and see" strategy if the impact possibility does
not go away. 

"Certainly it seems appropriate to play the 'wait and see' game until
after the 2013 observing opportunity," Harris stated. None of this
diminishes the opening that Apophis presents for purely scientific
investigations, which could incidentally contribute to the NEO hazard
issue, he said.

Harris said that he would not recommend a "deep impact" type of
scientific mission, "lest we have the misfortune to deflect it into a
keyhole, but other than that, Apophis is a very attractive mission
target."

A coming of age

Asteroid Apophis, and the discussions it has sparked are welcomed,
observed David Morrison, a space scientist and asteroid specialist at
NASA's Ames Research Center, situated in Silicon Valley, California.

"I am pleased that this dialog is taking place," Morrison said. "This is
the first time that serious possibilities for dealing with a real but
low-probability future impact have been discussed in a technically
professional way, rather than receiving the 'Hollywood treatment'".

Morrison said that he considers it remarkable that the Spaceguard Survey
has reached the
level of maturity where such an asteroid could not only be found, but
its orbit understood well enough to deal with "keyholes" and other
subtleties. "Apophis represents for me a symbol of the coming of age of
Spaceguard and of asteroid impact studies in general," he said.


The possibility of Apophis hitting Earth on April 13, 2036 is real,
Morrison said, even if the probabilities now seem to be very small.
"These probabilities represent uncertainties in our knowledge of the
orbit, not a failure of the science."

But whether the asteroid will strike Earth or not, Morrison concluded,
the challenge is to resolve which case is correct. "With more
observations over a longer time span, we will be able to tie this down."

_______________________________________________
existential mailing list
existential at transhumanism.org
http://www.transhumanism.org/mailman/listinfo/existential

----- End forwarded message -----
-- 
Eugen* Leitl <a href="http://leitl.org">leitl</a> http://leitl.org
______________________________________________________________
ICBM: 48.07100, 11.36820 http://www.ativel.com http://postbiota.org
8B29F6BE: 099D 78BA 2FD3 B014 B08A  7779 75B0 2443 8B29 F6BE