Testimony of Russell L. Schweickart, Chairman, B612 Foundation, before the Subcommittee on Science, Technology and Space of the Senate Commerce Committee, 7 April 2004, before the U.S. Senate Subcommittee on Science, Technology and Space dealing with defense against asteroid impacts.
|This color image of Eros was acquired by NEAR's multispectral imager on February 12, 2000, at a range of 1100 miles (1800 kilometers).
First I'd like to thank you for the invitation to speak with you today about this emerging public policy issue of near Earth objects (NEOs) threatening life on Earth. One might have thought, just a few years ago, that the subject of asteroids was one for space wonks and wanna-be astronauts and astronomers. But today the realization is rapidly dawning on the media and the general public that asteroids are a subject of more than passing interest!
More and more people are coming to know that some few of these asteroids do not silently pass the Earth, but indeed crash in, largely unannounced. On the rare occasions when this happens they can wreak havoc of a magnitude unprecedented in human history. At the upper limit impacts by large asteroids have caused global destruction leading to the virtually instantaneous extinction of life for most of the species living at the time. The dinosaurs were momentary witnesses to a billion megaton event of this kind 65 million years ago. At the lower limit of concern, but occurring much more frequently, we are dealing with events with an explosive force of 10-15 megatons. It is worth pointing out, however, that these small, most frequent events are more powerful than the blast from the most powerful nuclear weapon in the current U.S. nuclear arsenal.
Given the extremely low frequency of these natural events in combination with the extremely grave consequences when they occur, we find ourselves challenged to properly place this subject in our normal list of priorities. Inattention to infrequent events, regardless of their impact, is the "default" solution of choice given the crowd of issues continually burning around our feet.
Therefore the Committee is to be congratulated for its foresight and exemplary public service in realizing the importance of dealing with this issue now.
Perhaps the best logic path to bring the Committee to appreciate our recommendations for action is to briefly outline the key realities the founders of the B612 Foundation faced when we first came together back in October 2001. We are primarily a group of technical experts familiar with or working within the fields of space exploration and planetary science. We are astronauts, astronomers, engineers and a few others who are knowledgeable about the subject of comets and asteroids and their history of impacts with the Earth and other solar system bodies. We came together out of a deep concern that the threat to life implied in our knowledge of near Earth asteroids (NEAs) was not resulting in any organized effort to take action to protect the public from this hazard. We came together to explore whether or not something could be done, and if so, whether we could trigger a program to protect the public.
In summary, we faced the following facts:
1) Asteroid impacts with Earth have, do, and will continue to occur with devastating consequences to life.
2) Our detection program (the Spaceguard Survey) has produced a good statistical characterization of the overall threat and actual knowledge that at least 60% of the asteroids larger than 1 kilometer in diameter will not strike the Earth in the next 100 years.
3) Many impacts by asteroids less than 1 km in diameter, however, which occur hundreds of times more frequently than those over 1 kilometer, will cause unacceptable devastation at both local and regional levels.
4) The increasing capability of our detection programs in the next several years will result in a dramatic increase in the discovery rate of these smaller but very dangerous asteroids.
5) The media and the general public will become ever more aware of this threat and concerned that something should be done about it.
6) A known threat that can potentially destroy millions of lives AND can be predicted to occur ahead of time, AND prevented, cannot responsibly go unaddressed.
This inexorable logic led us to decide to take action and examine whether preventive measures could be taken to mitigate this threat, and if so, what specific course of action we would recommend.
|Click here for larger image. Asteroid belt estimated to contain over 1 million asteroids with diameter exceeding one kilometer.
It became immediately clear to us that the combination of advanced propulsion technologies and small space-qualified nuclear reactors, both operating in prototype form already, would be powerful enough, with reasonable future development, to deflect most threatening asteroids away from a collision with the Earth, given a decade or more of advance warning.
Nevertheless we saw two immediate problems.
First we lack the specific knowledge of the characteristics of NEAs necessary to design anything approaching a reliable operational system. We could readily show that the technology would exist within a few years to get to and land on an asteroid. We also determined that after arriving at the asteroid we would have enough propulsive energy available to successfully deflect the asteroid from an Earth impact a decade or so later. What was missing however was knowledge about the structure and characteristics of asteroids detailed enough to enable successful and secure attachment to it.
Second we recognized that before we would be able to gather such detailed information about NEAs there would likely be many public announcements about near misses and possible future impacts with asteroids which would alarm the general public and generate a growing demand for action. We felt strongly that there needed to be some legitimate answer to the inevitable question which will be put to public officials and decision makers, "and what are you doing about this?"
These two considerations led us to the conclusion that the most responsible course of action would be to mount a demonstration mission to a NEA (one of our choosing) which would accomplish two essential tasks; 1) gather critical information on the nature of asteroid structure and surface characteristics, and 2) while there, push on the asteroid enough to slightly change its orbit thereby clearly demonstrating to the public that humanity now has the technology to protect the Earth from this hazard in the future.
We furthermore determined that this demonstration mission could be done with currently emerging capabilities within 10-12 years.
We therefore adopted the goal of "altering the orbit of an asteroid, in a controlled manner, by 2015".
Reflecting the work that we have done to bring this goal to realization, a number of us wrote a descriptive article for Scientific American magazine entitled, The Asteroid Tugboat. Scientific American published it in the November 2003 issue of the magazine. I have provided reprints of this article to the Committee and I would like to submit a copy with this testimony and ask that it be incorporated in the record.
A key to implementing this mission is NASA's Prometheus Program. Shortly after B612 Foundation began work on outlining a mission to explore and deflect an asteroid NASA announced the formation of its Prometheus Program to develop and demonstrate technologies to permit routine human and robotic activity in space "beyond low Earth orbit".
The key technologies which NASA recognized would enable this capability are identical with what we had determined were necessary to demonstrate the capability to land on and deflect a near Earth asteroid, i.e., high performance electric propulsion systems and the space nuclear electric power systems to power them. Shortly after announcing the Prometheus Program NASA announced the Jupiter Icy Moons Orbiter (JIMO) mission complete with schematic representations of the spacecraft. Integral to the design of this mission were the very high performance engines and space nuclear power system which would be necessary to enable our B612 mission. We therefore adopted, as an explicit element of our design, the JIMO/Prometheus capabilities, recognizing that this was the most likely path to meeting the demonstration goal that we had set.
Mounting a mission to assure the public that when we discover an asteroid "with our name on it" we can deflect it from a life threatening impact on Earth does not require the development of additional new technologies. The key capabilities required are already "in the pipeline" of the existing Prometheus Program. No new NASA money is required, nor is a change in NASA's mission called for. What is required is that the B612 mission be incorporated within the Prometheus Program as a matter of policy.
Indeed, if one examines the technical requirements associated with the B612 mission, one sees not only a mission ideally suited to demonstrating the Prometheus technology, but a mission notably less demanding than the currently planned JIMO mission. One could then quite easily consider the B612 mission as either a follow-on or a precursor to the JIMO mission, depending on NASA's technical judgment as to where it fits most logically in their mission model.
The B612 mission also fits well into the President's Space Exploration Initiative. This mission both utilizes and graphically demonstrates the key enabling technologies for routine future operations "beyond low Earth orbit". It is an ideal way to demonstrate the technology and the greatly enhanced propulsive capability implicit in the Prometheus exploration program. In executing such a mission humankind will, for the first time in its history, have altered the trajectory of a cosmic body, a demonstration of evolving capability in space technology and exploration if there ever was one!
|Artist's concept of Muses-C spacecraft, flying down toward the asteroid.
A few final comments are perhaps appropriate.
Near Earth asteroids are a reality which is here to stay. In fact they will become far more prominent in the public mind as time goes on and our detection of them continues to improve. It is therefore appropriate that we take a more circumspect look at these sometimes unruly, but ever-present, neighbors. Near Earth asteroids are, in fact, both a threat and an opportunity.
Certainly we need to learn more about our capability to protect life here on Earth, and the sooner the better.
Visiting asteroids can also teach us a great deal about the origins of the solar system, and perhaps even the origins of life. Unlike the material of the Earth, which has been melted and processed through extensive geologic activity, the materials of small asteroids have not been so extensively reprocessed. They are fossil building blocks left over from the formation of the planets and as such can teach us a great deal about the original material from which the planets formed.
Perhaps even more important, asteroids, and especially the near Earth asteroids, are also the most readily accessible and rich reservoir of non-terrestrial resources available to us. The new space initiative has emphasized our determination to return to the Moon and then extend our capability outward to Mars and beyond. One of the purposes advocated for returning to the Moon is to explore and potentially develop the capability to utilize the resources there for human benefit. The possibility of extracting oxygen, water and perhaps other materials from lunar soils has long been advocated as a potential capability for reducing the cost of future space operations.
Yet these same resources, and others in rich abundance, characterize the makeup of asteroids. Unlike lunar materials, which are largely depleted of heavy minerals, the asteroids are quite rich in metallic elements, as well as those minerals which may provide water and oxygen. Furthermore it is significantly less expensive to fly to and from selected near Earth asteroids than to and from the Moon due to the virtual absence of gravitational forces associated with these bodies.
When commercial, entrepreneurial activity emerges into deep space it will undoubtedly include the development and exploitation of in-situ resources and services. Given the critical importance of benefit/cost analysis in any commercial venture it would be surprising if utilization of asteroidal resources, especially water, is not one of the first deep space initiatives attracting private capital.
Given then the infrequency of actually having to deflect an asteroid in order to avoid an Earth impact it is unlikely that humanity will ever need to develop a stand-alone planetary defense system. However, given the commercial, as well as the scientific value implicit in near Earth asteroids it is highly likely that operations to and from the asteroids will become a routine part of human space operations. One can readily imagine a time when visiting, using and even moving near Earth asteroids becomes a routine human capability. Simply calling on the "Ace Asteroid Mining and Moving Company" to nudge asteroid 2018 FA322 gently out of the way may then be all that is required to prevent an otherwise devastating event.
While the above scenario is somewhat fanciful, it is, given time, only slightly so. In the meanwhile, in the immediate future, we will be discovering an increasing number of potentially life threatening NEAs and the public will become justifiably concerned. Without a legitimate answer to this concern for their safety this concern could morph into alarm.
While many lives are lost every year in natural disasters of one kind or another, there are few natural disasters that can reliably be predicted, much less prevented. Throughout human experience we have been faced with comforting and compensating the devastated after the disaster is over. With near Earth asteroid impacts, however, we are confronted with a massive natural disaster that can be both predicted AND prevented, and the public will come to understand that this is the case.
Given the justifiable public expectation of being protected from both natural and manmade disasters it is incumbent on us to address this known threat responsibly. We therefore make the following specific recommendations:
1) We call on the Congress to task NASA with increasing the capability of the current Spaceguard Survey consistent with the recommendations of the recent NASA Near-Earth Object Science Definition Team report.
2) We call on Congress to direct NASA to incorporate the B612 mission goal of demonstrating the capability of landing on, exploring, and deflecting an asteroid as part of its Prometheus Program.
3) We call on Congress to request that OSTP initiate a high level study to develop a US Government policy for both national and international response to the deflection of near Earth asteroids.