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By Barbara Cherry, Legislative Affairs Office
: Asteroids:
Perils and Opportunities hearing before the Subcommittee
on Space and Aeronautics, Committee on Science, May 21, 1998.
Rohrabacher
, Chairman, (R-CA), Brown (D-CA), Cook (R-UT), Gordon (D-TN),
Bartlett
(R-MD), Hall (D-TX), Roemer (D-IN), Weldon (D-FL), Luther
(D-MN)
Dr.
Clark Chapman, Southwest Research Institute; Dr. William Ailor,
The Aerospace Corporation; Dr. Gregory Canavan, Los Alamos
National Laboratory; Dr. John Lewis, University of Arizona;
Dr. Carl Pilcher, NASA.
Chairman Rohrabacher opened the hearing by commending
Congressman Brown for his leadership and long track record
of pushing the Executive Branch to deal with the issue of
cataloging and characterizing asteroids. He stated that the
potential impact of these hazardous objects is one of national
security, economic as well as scientific interest. Congressman
Rohrabacher noted that the potential to mine asteroids for
metals, minerals and other resources that can be used to build
large structures in space was an important aspect of the hearing.
Mr. Rohrabacher chided NASA for not walking the talk
by funding the Near Earth Object (NEO) search program at the
levels suggested in the Shoemaker Report. He noted that NASA
has no trouble finding $50 million for a program pushed by
the Vice President to transmit pictures of Earth into everyones
living room and cannot find a few million dollars to increase
the likelihood of cataloguing all of the potentially hazardous
NEOs l km or larger.
Congressman Brown echoed his long-standing interest
in this subject and the importance of addressing the issue
of cataloging and characterizing NEOs even though the risk
of impact is small because of the enormous potential catastrophic
consequences.
Dr. Chapman discussed the possibility
that an asteroid or comet might strike Earth in our lifetime,
perhaps destroying civilization as we know it. He presented
a chart which illustrated the chances of dying from an asteroid
impact against selected other causes (USA). Congressman Cook
noted that the chances of dying from an airplane crash and
from an asteroid impact were both l in 20,000.
Dr. Chapman noted that if a mile-wide asteroid
hit earth, it would create a hole larger than Washington DC,
it would be deeper than 20 Washington monuments stacked on
top of each other, ruin agriculture production, and hundreds
of millions to billions of people would die. He noted that
the consequences were devastating and, therefore, it was prudent
to implement the recommendations contained in the Shoemaker
Report of cataloging 90% of all of the NEOs with diameters
of 1 km or larger within a decade. This would reduce by a
factor ten the uncertainty of knowing if an asteroid were
headed toward Earth and would likely provide sufficient time
to try and deal with the situation.
Dr. Pilcher testified that NASA is committed
to the goal of cataloging 90% of all of the NEOs with diameters
larger than 1 km within a decade and that we are on track
to do so. He stated that NASA has a rich program of research
on asteroids and comets which will provide essential information
if the Nation were ever to divert an asteroid. Dr. Pilcher
stated that the Space Science Strategic Plan includes as a
objective, to catalog 90% of the NEOs with diameters larger
than 1 km within 5-6 years and NASA has put into place a program
to do this. Dr. Pilcher stated that the budget has been doubled
to $3 million and NASA will maintain at least this level of
funding in the future. Dr. Pilcher outlined all of the elements
of the NEO Search program and where increases in the budget
have enabled NASA to support new activities. He discussed
the Partnership Council, a Council chaired by the Administrator
and General Estes of the Air Force to discuss issues of mutual
concern to both agencies -- NEO detection is one issue which
the Partnership Council is addressing. Dr. Pilcher stated
that the only recommendation that NASA is not implementing
from the Shoemaker Report was the recommendation to build
a dedicated 2 meter telescope -- because planned upgrades
to existing telescopes can do the job. Dr. Pilcher told the
Committee that NASA would do what it takes to do the job right.
Dr. Canavans testimony addressed several
issues. He stated that new technology developed since the
Shoemaker Report was issued has increased the detection rate.
He emphasized that one area that has not been addressed is
long period comets whose orbits intersect the Earth. He said
there is no clear concept how to do this and it may constitute
as high as 50% of the threat. Dr. Canavan also stated that
characterization of asteroids is important if one were to
try and alter the course of an asteroid or comet. He discussed
the Clementine II mission, which he said represented excellent
collaboration between NASA and DOD before it was canceled.
Dr. Canavan closed by saying that the current level of funding
for NEO searches is 1/3 to _ too low to adequately do the
job.
Dr. Ailor discussed the risk the Leonid meteor
shower will pose this November. He stated that in a normal
year one see 10-15 meteors per hour and this November there
will be as many as 200-5,000 meteors per hour traveling at
a speed of approximately 155,000 miles per hour. He discussed
the recommendations from a recent Conference that was held
to address this issue: 1) During the period, satellite controllers
should be on duty and check the health of the satellites frequently,
2) orient satellites so that sensitive components are shielded
from the oncoming stream of particles and 3) recovery plans
should be in place in the event of a system failure.
Dr. Lewis discussed the economic value of asteroids
as a source to mine minerals and materials for earth or to
produce materials in space for future space transportation.
He noted the very low departure speed required to lift off
from an asteroid for a return trip to Earth. Dr. Lewis stated
that the keys to successful importation of materials from
space are lower launch costs and careful choice of exploitation
targets to favor those that are most accessible and have the
richest resource concentrations.
Chairman Rohrabacher stated that NASA has not
been spending adequate funding to search for NEOs as recommended
in the Shoemaker Report. Dr. Pilcher noted that, the Office
of Space Science has issued their Strategic Plan which includes
a goal of cataloging 90% of the 1 km asteroids, that NASA
funding wasnt adequate to accomplish this goal, and
NASA had doubled the funding of the NEO program.
Mr. Rohrabacher asked Dr. Pilcher how many of
the asteroid missions he discussed were actually in the budget.
Dr. Pilcher replied that DS-1, DS-4, Contour, STARDUST, Comet
Nucleus Sample Return, and Pluto Kuiper Express were all assumed
in NASAs budget.
Congressman Gordon asked if NASA was the only
Agency working on the problem. Dr. Pilcher responded that
NASA supports researchers at Universities to address this
issue and works closely with the Air Force. He stated that
NASA is developing collaborations with the international community
as well. Mr. Gordon asked if the Federal Government was coordinating
adequately. Dr. Chapman responded that FEMA has little appreciation
for the hazard of such an event. Dr. Canavan stated that interagency
cooperation between NASA and the Air Force hasnt percolated
down to the troops beyond the Administrator and General Estes.
Congressman Hall asked if we have to have a
calamity before anyone takes something seriously and noted
that it is an international problem and should have international
participation. He asked how much NASA is spending on search
activities. Dr. Pilcher responded that NASA is spending $3
million per year and approximately $1 billion over the next
decade in asteroid/comet missions. Mr. Hall questioned if
NASA is actually spending all of the money allocated for the
purposes which the Congress appropriated the funds, indicating
that Life and Microgravity funding was being spent for hardware
and not research.
Mr. Roemer noted that Dr. Chapman had provided
the sound bite for the evening news-- that a mile wide
asteroid could hit the Earth tomorrow and we wouldnt
know anything about it. He asked if the Federal Agencies
had held discussions among themselves on what you would need
to do to coordinate a response if an impact were imminent.
The witnesses indicated that not much had been done.
Mr. Rohrabacher stated that one needs to put
things in perspective and perhaps we arent spending
money wisely. He noted that Mission to Planet Earth is budgeted
at $1.4 billion and perhaps it makes more sense to spend additional
money on looking for NEOs and improving interagency coordination
instead of spending money on Mission to Planet Earth. He stated
that he hoped the Congress would move forward and lay the
ground work for the Clementine II mission.
Congressman Hall said he thought the hearing
was a waste of time unless we arrive at some actions
-- if it is money we need to know how much. Both he
and Congressman Rohrabacher charged each of the witnesses
to draft a two page action plan on what is needed to address
the NEO issue and what policies need to be developed to meet
the challenges that a NEO impact threat poses.
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