NASA to Lead Global Asteroid Response
nature - NASA will play a leading part in protecting the United States and the world from the threat of a dangerous asteroid strike, according to letters sent by John Holdren, director of the White House Office of Science and Technology Policy (OSTP), to Congressional committee leaders on Friday.
Holdren's letters to the Senate Committee on Commerce, Science, and Transportation and the House Committee on Science and Technology assign responsibilities to the US space agency that go beyond its 2005 Congressional mandate to detect and track 90% of potentially hazardous asteroids with a diameter greater than 140 metres. To date the agency has found 903 of the estimated 1,050 asteroids with diameters of a kilometre or more passing within about 50 million kilometres of the Earth.
NASA will be mandated to notify other organizations, including the US Federal Emergency Management Agency (FEMA), if a dangerous asteroid is found, and to drive research and development on the capability needed to deflect the rock.
In assigning NASA's new asteroid defence role by 15 October, Holdren was meeting a requirement of the 2008 NASA Authorization Act. Under the act OSTP is also required to choose an agency or agencies that would protect the United States and implement a deflection, if one were necessary.
Ramping up funds
So far, NASA's mandate to track near-Earth objects has been largely unfunded.
Former US astronaut Russell 'Rusty' Schweickart, who has advocated for the United States and other countries to be more active in planetary defence against asteroids, says that NASA's amplified responsibilities give it a platform for asking Congress for extra funds. "This is a major step forward," he says. Schweickart co-chairs NASA's Ad-Hoc Task Force on Planetary Defense, set up by the agency in March with the expectation that it would be assigned a leading role in coordinating asteroid defence.
Holdren also envisions a key role for FEMA in passing along news of the impending strike to states and territories that could be affected. "The essence of the planned notification approach is to utilize existing communications resources and mechanisms resident at FEMA," he wrote in the letters.
The letters add that NASA would make additional notifications through the US State Department and diplomatic channels to other countries that could be affected, and to the United Nations. Those notifications would be updated by NASA as more information became available about the threat, up until one day in advance of the projected impact, Holdren says.
The ad-hoc task force released a report on 6 October listing actions NASA should take on planetary defence. It recommended the establishment of a Planetary Defense Coordination Office, with an annual budget of around US$250 million, and the initiation of a mission to prove capability to deflect an asteroid.
Holdren notes in his letters that the President's budget for the 2011 fiscal year asks for a three-fold increase in funds for near-Earth object detection activities, from $5.8 million to $20.3 million. It remains to be seen whether next year's budget request will cater for the agency's additional responsibilities. "It's especially important that those activities discussed by the OSTP be supported by a proposed budget to cover those modest costs required," says Tom Jones, another former astronaut and co-chair of the ad-hoc task force.
Despite being fairly specific about notification procedures, Holdren's letters were much vaguer about the methods for deflecting an asteroid on a collision course with Earth. He says that the US government's assessment of deflection options is still at an early stage.
"As NASA tests in space the techniques and technologies needed for deflection, the OSTP should re-examine this question and identify the lead agency — or agencies — to actually execute a deflection demonstration," says Jones.
TUESDAY, OCTOBER 26, 2010
The Imperative of Asteroid Defense
The aftermath of the Tunguska Event, an impact from space in central Siberia.
Check out this Op-Ed in today's New York Times from Russell Schweickart, former astronaut and co-chair of the Task Force on Planetary Defense.
Asteroid defense is a subject that doesn't get nearly enough attention. Of course we don't want to alarm people, but at the same time, maybe people need to be a little more alarmed! That may be the only way to really see some action on this front.
When you think about it, it's sort of surprising that we don't devote more energy to asteroid defense. We actively scan the skies for near-Earth objects, but in terms of actually deflecting an asteroid from a collision, our plans at this point are only theoretical. It's surprising because it seems like we should be able to get everyone on board with this mission. For some people, space exploration is seen as an esoteric endeavor, lacking practical purpose. But what could be more practical than defending the planet from a clear and present danger? To me, asteroid defense should be much easier to rationalize than studying the geology of the Moon or sending astronauts to Mars.
The problem is that this is an issue that sounds fanciful. We've all seen Armageddon. You start talking about preventing an asteroid collision and everyone thinks about Bruce Willis flying up there to blow it up, with Aerosmith providing the soundtrack.
But we all know what happened to the dinosaurs. What's so far-fetched about an asteroid collision? Even though impacts of that size are exceedingly rare, smaller objects are much more common and can do plenty of destruction. Let us not forget the Tunguska Event, the 1908 impact of a space object in central Russia that caused an explosion estimated to be as much as 1000 times more powerful than the atomic bomb dropped on Hiroshima. That was more than 100 years ago, and it came down in such a remote corner of the Earth that few people other than space enthusiasts even know about it today. But it could just as easily have come down in New York City, in 2008 rather than 1908. As Schweickart points out, this sort of impact occurs every 200 to 300 years, statistically speaking. But that doesn't mean we have nothing to worry about. If you average two such impacts in 400 years, they don't have to be 200 years apart.
This is not the sort of project that we can put off indefinitely. A mission to Mars can be delayed five or ten years and it won't make much difference; the lives of millions don't hang in the balance. But what if we were to discover an object that's going to hit us in the next five years? Is that sufficient lead time to get the project going today? Would we have to contend with congressional skepticism? I can hear the carpers now: "Are we really going to spend 10 billion dollars on a project to protect us from this rock you say is going to hit us? We don't even know where it's going to land, do we?"
If there were more champions for this cause, I can imagine it might be similar to the fight over climate change. There would be those who would want to prepare for it, and those who would think it costs too much to prevent something that might not cause any harm in our lifetime. But think of the huge amounts of money spent on missile defense during the cold war. That danger was very real, but ultimately, thankfully, nothing came of it. The expenditures required for asteroid defense would be tiny by comparison. But unlike the prospect of nuclear war, which was possible but avoidable, the impact of a large object from space is inevitable given enough time. We just don't know when it might come. It could be 100, 200 or 300 years from now, but it could be much sooner than that. We owe it to the citizens of Earth -- even those who may not be born yet -- to start preparing for this scenario now.
President Obama's new plan for the future of NASA calls for a manned mission to an asteroid. Assuming this directive is not changed in the years to come, this will be an astonishing achievement. But even more than a manned mission to Mars, it may prove to be of vital importance to the future of life on Earth. We won't just be going to look around and take some soil samples. We'll be learning how to interact with an asteroid. And one day that knowledge could save millions of lives.
Scientists will be quick to point out that catastrophic impacts are still quite rare, and furthermore, the chances that an impact will occur near a major metropolitan area are smaller still. But we might not be able to determine the object's precise trajectory until it's too late. An object capable of destruction equivalent to Tunguska could land anywhere on Earth, killing millions, or killing no one. But a serious effort to plan for this contingency will be worth the cost no matter how many lives are at stake. There are certainly more immediate concerns on our horizon, but such will always be the case until the day we find the big one coming straight for us.
Business Innovation - Let's Shrink Wrap an Asteroid, Let Me Explain - Planetary Defense Concept
By Lance Winslow
Perhaps you or someone you know has been involved in the marine industry? If so, then you probably realize that in colder climates often boats are shrink-wrapped for the winter months. Yes, just as you might do with your leftovers before you put them in the refrigerator. It turns out this works very well to protect them from the winter. Then when springtime comes the boats are thawed out and the shrink-wrapped is removed. The cost for doing this is about $2500-$4500 for about a 20 foot boat. Perhaps during the recession you can get a little bit better deal?
Well, that's how you shrink-wrapped a boat, but what about shrink-wrapping an asteroid in space? Yes, I know that sounds funny, but I'm not talking science fiction here, I think it has a real benefit. Let me explain. First of all if a very large asteroid or comet were to hit the Earth, there is a potential that it could cause all species living on the surface of the planet to go extinct. Therefore it makes sense to have a planetary defense system to go out into space and either destroy, divert, or deflect the asteroid. Now then, what if we shrink wrap it? With what you ask?
Okay so we shrink wrap an asteroid in a Graphene Coating and then hit it with a laser to propel a vibrational frequency wave which causes the ion-bonds to become weak while causing the Graphene to attract. Then we allow it to unwrap, and turn off the energy now we have a sheet of asteroid to mine, or break apart in sections as it goes, blasting a little bit at a time off of the graphene coating, which is now a very large sheet floating through space.
We have unraveled the asteroid's mass into a thin layer of dust, then send the dust in all directions. This means it is no longer a threat to Earth. Please consider all this, because the concept is actually viable.
1.-The arXIv Blog at MIT, Blog post on October 21, 2010 entitled; "Mass Can Be Created Inside Graphene, Say Physicists - The Amazing Properties of Graphene Now Include the Ability to Create Mass, According to a New Mathematical Prediction."
Lance Winslow is a retired Founder of a Nationwide Franchise Chain, and now runs the Online Think Tank. Lance Winslow believes it's hard work to write 21,300 articles; http://www.bloggingcontent.net/
Ocean Impacts and Their Consequences
by PAUL GILSTER on OCTOBER 27, 2010
It’s good to see asteroid deflection occasionally popping up in the news, thanks to the efforts of people like former astronaut Rusty Schweickart, whose efforts as co-chairman of the Task Force on Planetary Defense of the NASA Advisory Council are complemented by his work for non-profits like the B612 Foundation. Schweickart is worried about the potential consequences of even a small asteroid impact, pointing to the Tunguska event of 1908, in which 800 square miles of Siberian forest were flattened in the kind of strike that occurs every 200 to 300 years.
Bigger asteroids are, obviously, a far greater danger, and while they’re much rarer, they do have the capability of wiping out entire species, as may well have occurred some 65 million years ago in the destruction of the dinosaurs. In his recent New York Times article, Schweickart notes what we need to do:
With a readily achievable detection and deflection system we can avoid their same fate. Professional (and a few amateur) telescopes and radar already function as a nascent early warning system, working every night to discover and track those planet-killers. Happily, none of the 903 we’ve found so far seriously threaten an impact in the next 100 years.
Nonetheless, asteroids demand a constant vigilance. Schweickart continues:
Although catastrophic hits are rare, enough of these objects appear to be or are heading our way to require us to make deflection decisions every decade of so.
A deflection capacity is something NASA needs to be looking at, and the report of the Task Force on Planetary Defense urges that financing for it be added to the NASA budget. Schweickart believes that $250 to $300 million, added annually over the next ten years, would allow our inventory of near-Earth asteroids to be completed and a deflection capability to be developed, after which a maintenance budget ($50 to $75 million per year) would keep us tuned up for potential deployment.
Underscoring the need for a deflection capability is the work of Elisabetta Pierazzo (Planetary Science Institute), whose forthcoming paper in Earth and Planetary Science Letters focuses on two impact scenarios, 500-meter and 1-kilometer asteroids hitting a 4-kilometer deep ocean. What Pierazzo finds is that an ocean strike could deplete the Earth’s protective ozone layer for several years, resulting in a spike in ultraviolet radiation levels that would, among other things, make it more difficult to grow crops (not to mention its effects on other life forms).
Pierazzo and team’s atmospheric simulations show a global perturbation of upper atmosphere chemistry, as water vapor and compounds like chlorine and bromide alter the ozone layer to create a new ozone hole. Adds Pierazzo:
“The removal of a significant amount of ozone in the upper atmosphere for an extended period of time can have important biological repercussions at the Earth’s surface as a consequence of increase in surface UV-B irradiance. These include increased incidence of erythema (skin reddening), cortical cataracts, changes in plant growth and changes in molecular DNA.”
Ultraviolet radiation intensity can be expressed by the ultraviolet index (UVI), which indicates the intensity of UV radiation at the surface, with the higher numbers tending toward damage to skin and eyes. While a UVI of 10 is considered dangerous, resulting in burns to fair-skinned people after short exposure, values up to 18 are occasionally recorded at the equator. The highest recorded UVI is 20, recorded at a high-altitude desert in Puna de Atacama, Argentina.
Modeling a strike by an asteroid that hit at latitude 30 degrees north in the Pacific Ocean in January, Pierazzo’s simulations show that a 500-meter asteroid impact would result in a major ozone hole, boosting UVI values to over 20 for several months in the northern subtropics. A 1-kilometer asteroid would drive the UVI in certain areas to a sizzling 56, while boosting UVI values over 20 within a 50-degree latitude band north and south of the equator for about two years. The affected band’s northern end would include Seattle and Paris, while its southern end reached New Zealand and Argentina.
“A level of 56 has never been recorded before, so we are not sure what it is going to do,” adds Pierazzo. “It would produce major sunburn. We could stay inside to protect ourselves, but if you go outside during daylight hours you would burn. You would have to go outside at night, after sunset, to avoid major damage.”
We always tend to depict asteroid impacts in terms of their direst consequences as a way of illustrating the magnitude of the threat. But it’s chastening to learn that even a survivable impact like those Pierazzo and team have modeled would create serious environmental damage even if loss of life could be prevented. All this assumes, too, an asteroid that strikes in the ocean (the most likely scenario). There’s no question that building up our planetary defense against such impacts is the best insurance we could create, stopping potential impactors before they near our planet.
The paper is Pierazzo et al., “Ozone perturbation from medium-size asteroid impacts in the ocean,” in press at Earth and Planetary Science Letters (abstract). Jeremy Hsu’s article on this work in LiveScience is excellent.
A New Column by Former Executive Director Louis Friedman.
October 27, 2010
Starting on Planetary Defense
It is unlikely that anytime soon an asteroid or comet will impact Earth and cause devastating or large-scale damage. But we will probably soon find some object that is deemed potentially hazardous, one that might pose a future danger to Earth. That will be considered a threat. When that happens, defensive action may be contemplated. The discovery of thousands of Near-Earth Objects (NEOs) makes us much more aware of previously unknown possibilities and also much more sensitive to the devastating consequences of an impact.
The President’s Science Advisor, Dr. John Holdren, has just sent a ten page letter to the U.S. Congress (PDF) dealing with Planetary Defense. The letter is a result of Congress asking the Administration for a policy and plan to protect the United States from a potentially hazardous NEO.
It’s great to have this issue addressed. Ignorance should no longer be an excuse for inaction. The Administration’s letter is one more in a series of reports and studies that define the problem and call for more action – observations and tracking of NEOs, analyzing their composition and structure (including with space missions), and studies of mitigation techniques (deflecting a potentially hazardous object). We have previously mentioned reports from the Association of Space Explorers (PDF) -- the astronauts and cosmonauts organization which has led international consideration of this issue, the International Academy of Astronautics, and a Working Group of the United Nations Committee on Peaceful Uses of Outer Space (PDF) , of which The Planetary Society is a member. A special task force of the NASA Advisory Council also has issued a very strong report (PDF) calling for NASA leadership in both public information and global cooperation addressing the issue. Board member Bee Thakore and I prepared a paper and presentation on the subject to the International Astronautical Congress in 2009 .
The Association of Space Explorers, with strong leadership by former astronauts Rusty Schweickart and Tom Jones (a Planetary Society Advisor), is also conducting a series of international workshops developing recommendations for mitigation methods and global policy. Much of their focus has been on the United Nations.
Progress is also being made on the science and technology. The pace of observations has quickened, and more NEOs of smaller and smaller size are being discovered. Space missions are being conducted. In just two weeks the Deep Impact spacecraft, which sent an impactor into a comet back in 2005, will pass by and observe closely Comet Hartley 2. Calls to build more dedicated observatories on Earth, and in space, need to be developed into firm proposals for funding and implementation. One problem is that no federal agency, not even NASA, has the prime responsibility for planetary defense -- hence no mission proposals have yet been generated.
While NASA is far ahead in consideration of the issue, the issue has also been addressed in Europe, particularly England, and in Russia; but only addressed – no programs or plans have been made. The lack of defined policy in the U.S. is mirrored throughout the world. Observation programs are not well funded and space missions are only proposed for science investigations, not for advancing planetary defense readiness.
Dr. Holdren’s letter is very welcome. It should help advance United States government planning. He reaffirms NASA’s lead responsibility for detection of NEOs. He adds that NASA should even lead in the study of mitigation and deflection, coordinating with other federal agencies, including the Department of Defense, Federal Emergency Management Agency and Department of Homeland Security. He also recommends that the U.S. continue to coordinate with international efforts to study the problem.
I am personally uneasy about NASA being the lead agency to consider mitigation, even though at the moment they know more about the subject than other parts of government. But mitigation involves consideration of nuclear weapons, and deflection of asteroids can be considered a weapon system. Having that as part of NASA’s mission needs some debate (especially if it detracts from space exploration). Inter-agency discussion can help resolve who should be lead; thus, the Administration’s recommendations are a valuable step forward. But it is not enough of a step. Any consideration of NEOs should be international. No nation can consider deflection of a potentially hazardous object unilaterally.
It’s my view that spacefaring nations should organize an ad-hoc task force, which someday might evolve to a treaty organization (analogous to NATO) to address policies, protocols and plans for dealing with the threat of a potentially hazardous object hitting Earth. The United States could, and should, lead by proposing such a task force. We need consideration soon, not because an impact is likely soon, but, because the threat of an impact is likely soon. The Administration’s letter to Congress should have also called for an international task force, clearly stating that NEO detection, observation, investigation, analysis, mitigation and potential deflection are global issues.
Now, about that asteroid…A few weeks ago, I grabbed one of the many unread magazines on my nightstand as I headed to the airport. After we were in the air, I took the magazine out (the June issue of The Atlantic) and I immediately noticed the cover art: a fiery asteroid hurdling towards Earth. The title of the cover story was “The Sky is Falling”, and the subtext read: “It’s inevitable: asteroids with the power to annihilate us will come this way. Can NASA divert them before it’s too late?” Whoa! Why haven’t I heard about this before, and why isn’t anyone panicking?!?!
The article argues that the odds of a life-annihilating space rock hitting our planet is much greater than we once thought, and that such an impact would disrupt our climate pattern and trigger a prolonged period of global cooling. Of course, none of us would be around to care very much, but that’s beside the point. Depressed, I put on my headphones and started to watch TV (it was a JetBlue flight). As I surfed through the channels, I stumbled upon a History Channel documentary on-I’m not kidding-how an asteroid might destroy our planet! This was officially the worst flight of my life. Then, in early October, I learned that a meteor entered the Earth’s atmosphere and burned up over Sudan. While the meteor did not pose a threat to us due to its small size, the frightening part of the story is that NASA only became aware of the meteor’s existence and its Earth-bound trajectory just twenty-fours earlier! I say forget about bailing out the automotive industry, send my tax dollars instead to the folks tracking those rocks in space.
I know what you’re saying: Adrian, stop worrying about this questionable threat, these encounters you’ve had with asteroids and meteors are just a coincidence. You’re probably right, but I can’t help but wonder that maybe all of this “green” stuff is just a waste of time, or a way to pass time, until God hits the reset button and the world turns dark and cold again. He told Noah that He would never destroy the Earth again with a flood, but He never said anything about an asteroid.
Finally, back in November, I highlighted the threat of asteroids extinguishing life on Earth sometime in the future, thus making all of this “green” stuff a waste of time (see “All Greened Out (Until the Asteroid Comes)“). Well, it happened again on Monday-another asteroid came within 46,000 miles of the planet and it wasn’t detected until two days before it zoomed by. Asteroid 2009 DD45 was about two hundred feet long, big enough to create damage equivalent to a nuclear blast if it had struck the planet. If I wasn’t paranoid back in November, I am now.
SPACE.com Senior Writer
National emergency plans for natural disasters can also work in the unlikely scenario of an asteroid strike on the U.S., according to a letter to Congress by the White House's top science adviser, SPACE.com has learned.
The 10-page letter by John Holdren, director of the White House Office of Science and Technology Policy, adds that the U.S. has a responsibility to the world as the country most capable of detecting space rocks that threaten Earth. The Oct. 15 letter obtained by SPACE.com is addressed to the leaders of the House Committee on Science and Technology.
Holdren states that NASA must continue leading efforts to close the gap in detecting and perhaps deflecting near-Earth objects (NEO). The U.S. space agency already has the duty of alerting the rest of the government about any threatening space objects.
Holdren's letter also laid out the duties of other federal agencies in handling emergency communications and response. It called for a "senior-level interagency simulation exercise" to test impact-response plans before the United States is confronted with an actual asteroid impact.
"My immediate reaction is that it represents the most detailed consideration of the U.S. government's response to the NEO threat to date, more clearly delineating communication links and responsibilities than had previously been the case," said Clark Chapman, space scientist at the Southwest Research Institute in Boulder, Colo.
Going on alert
According to Holdren's letter, the Federal Emergency Management Agency, under the Department of Homeland Security, has the main responsibility on the ground in the U.S. FEMA can rely in part upon the National Warning System, which was designed to alert U.S. citizens to a Cold War nuclear attack.
The Department of Defense would work with NASA on possible mitigation or deflection scenarios that involved military resources.
Meanwhile, the Department of State would help coordinate any international warnings or responses in a deep-impact scenario that affects more than just the U.S. It has experience notifying other countries about re-entering human-made space objects, including the defunct USA-193 spy satellite that was ultimately destroyed by a U.S. Navy missile.
"The United States is currently the world leader in NEO detection activities and will have a vital role to play in such communications, irrespective of whether the direct risk to the United States or its territories is considered low," Holdren said.
A NASA advisory council recently suggested that the space agency set up an official Planetary Defense Coordination Office to lead protection efforts against threatening asteroids or comets.
Finding the threat
NASA has begun closing in on its congressionally directed goal of finding at least 90 percent of all NEOs with a diameter of 1 kilometer or greater. Search teams had discovered about 903 of an estimated 1,050 NEOs in that size category as of Oct. 1, and the space agency plans to reach its 90 percent detection goal by the end of this year.
Just 149 of the discovered objects have orbits that could possibly bring them into collision with Earth, and none present an impact threat within the next 100 years. Another 993 objects less than one kilometer in diameter also have orbits that could someday pose a threat to our planet.
Yet NASA estimates that the 6,416 known NEOs in the smaller size category, less than 1 kilometer wide, represent just five percent of the expected count. In other words, there are probably many more objects out there that represent a possible threat to Earth.
Facing the future
Some of those objects were discovered more recently by NASA's sky-mapping WISE mission, which is slated to end in January 2011. But there are possible plans for ground-based telescopes that could join the hunt, such as the Air Force's Space Surveillance Telescope and the Large Synoptic Survey Telescope.
The National Research Council and NASA also suggested the possibility of a dedicated asteroid hunter that would fly in a Venus-trailing orbit. No firm plans have been made for this.
President Barack Obama's new National Space Policy and plan for human spaceflight has also targeted a human mission to an asteroid by 2025. That could prove a useful dry run of sorts for any future efforts that might need to deflect an asteroid away from Earth.
"The planning, required capabilities, and ultimate execution of such a mission also would parallel most aspects of a potential robotic asteroid-deflection mission, providing valuable experience in asteroid-rendezvous techniques," Holdren said.
SPACE.com's Space Insider Columnist Leonard David contributed to this report from Las Cruces, N.M.
Humans to Asteroids: Watch Out!
By RUSSELL SCHWEICKART
Published: October 25, 2010
Times Topic: Asteroids
A FEW weeks ago, an asteroid almost 30 feet across and zipping along at 38,000 miles per hour flew 28,000 miles above Singapore. Why, you might reasonably ask, should non-astronomy buffs care about a near miss from such a tiny rock? Well, I can give you one very good reason: asteroids don’t always miss. If even a relatively little object was to strike a city, millions of people could be wiped out.
Thanks to telescopes that can see ever smaller objects at ever greater distances, we can now predict dangerous asteroid impacts decades ahead of time. We can even use current space technology and fairly simple spacecraft to alter an asteroid’s orbit enough to avoid a collision. We simply need to get this detection-and-deflection program up and running.
President Obama has already announced a goal of landing astronauts on an asteroid by 2025 as a precursor to a human mission to Mars. Asteroids are deep-space bodies, orbiting the Sun, not the Earth, and traveling to one would mean sending humans into solar orbit for the very first time. Facing those challenges of radiation, navigation and life support on a months-long trip millions of miles from home would be a perfect learning journey before a Mars trip.
Near-Earth objects like asteroids and comets — mineral-rich bodies bathed in a continuous flood of sunlight — may also be the ultimate resource depots for the long-term exploration of space. It is fantastic to think that one day we may be able to access fuel, materials and even water in space instead of digging deeper and deeper into our planet for what we need and then dragging it all up into orbit, against Earth’s gravity.
Most important, our asteroid efforts may be the key to the survival of millions, if not our species. That’s why planetary defense has occupied my work with two nonprofits over the past decade.
To be fair, no one has ever seen the sort of impact that would destroy a city. The most instructive incident took place in 1908 in the remote Tunguska region of Siberia, when a 120-foot-diameter asteroid exploded early one morning. It probably killed nothing except reindeer but it flattened 800 square miles of forest. Statistically, that kind of event occurs every 200 to 300 years.
Luckily, larger asteroids are even fewer and farther between — but they are much, much more destructive. Just think of the asteroid seven to eight miles across that annihilated the dinosaurs (and 75 percent of all species) 65 million years ago.
With a readily achievable detection and deflection system we can avoid their same fate. Professional (and a few amateur) telescopes and radar already function as a nascent early warning system, working every night to discover and track those planet-killers. Happily, none of the 903 we’ve found so far seriously threaten an impact in the next 100 years.
Although catastrophic hits are rare, enough of these objects appear to be or are heading our way to require us to make deflection decisions every decade or so. Certainly, when it comes to the far more numerous Tunguska-sized objects, to date we think we’ve discovered less than a half of 1 percent of the million or so that cross Earth’s orbit every year. We need to pinpoint many more of these objects and predict whether they will hit us before it’s too late to do anything other than evacuate ground zero and try to save as many lives as we can.
So, how do we turn a hit into a miss? While there are technical details galore, the most sensible approach involves rear-ending the asteroid. A decade or so ahead of an expected impact, we would need to ram a hunk of copper or lead into an asteroid in order to slightly change its velocity. In July 2005, we crashed the Deep Impact spacecraft into comet Tempel 1 to learn more about comets’ chemical composition, and this proved to be a crude but effective method.
It may be necessary to make a further refinement to the object’s course. In that case, we could use a gravity tractor — an ordinary spacecraft that simply hovers in front of the asteroid and employs the ship’s weak gravitational attraction as a tow-rope. But we don’t want to wait to test this scheme when potentially millions of lives are at stake. Let’s rehearse, at least once, before performing at the Met!
The White House Office of Science and Technology Policy has just recommended to Congress that NASA begin preparing a deflection capacity. In parallel, my fellow astronaut Tom Jones and I led the Task Force on Planetary Defense of the NASA Advisory Council. We released our report a couple of weeks ago, strongly urging that the financing required for this public safety issue be added to NASA’s budget.
This is, surprisingly, not an expensive undertaking. Adding just $250 million to $300 million to NASA’s budget would, over the next 10 years, allow for a full inventory of the near-Earth asteroids that could do us harm, and the development and testing of a deflection capacity. Then all we’d need would be an annual maintenance budget of $50 million to $75 million.
By preventing dangerous asteroid strikes, we can save millions of people, or even our entire species. And, as human beings, we can take responsibility for preserving this amazing evolutionary experiment of which we and all life on Earth are a part.
Russell Schweickart, a former astronaut, was the co-chairman of the Task Force on Planetary Defense of the NASA Advisory Council.
NAC Planetary Defense Task Force Makes Five Recommendations to NASA
Written by Marcia Smith
Monday, 25 October 2010 21:03
The NASA Advisory Council's (NAC's) Task Force on Planetary Defense made five recommendations to NASA in its report to NAC, which accepted the report on October 6. The Task Force was co-chaired by two former astronauts, Tom Jones and Rusty Schweickart. In this context, planetary defense means defending Earth from Near Earth Objects (NEOs) -- asteroids and comets -- headed our way.
The recommendations are:
- Organize for Effective Action on Planetary Defense
- Acquire Essential Search, Track and Warning Capabilities
- Investigate the Nature of the Impact Threat
- Prepare to Respond to Impact Threats
- Lead U.S. Planetary Defense Efforts in National and International Forums
The White House Office of Science and Technology Policy recently sent letters to Congress in response to a provision in the 2008 NASA Authorization Act on agency roles and responsibilities in dealing with the NEO threat. It gave NASA a lead role in many aspects of NEO detection and cataloging, but deferred decisions on who is in charge of mitigating the threat. It did identify NASA as the lead agency to perform analysis and simulation to inform future decisions on mitigation options.