On April 26, 2010, NASA Deputy Administrator Lori Garver discussed the new NASA plan at the Center for Strategic and International Studies (CSIS). A portion of her comments dealt directly with NEOs and the reasons for exploring them, those portions are given here:
Before we reach the surface of Mars with humans, we'll explore an asteroid, by 2025. The President announced that unprecedented goal in Florida. NASA engineers have been looking at candidates for a NEO mission that could launch in 2025. Because of orbital dynamics, launch date drives the specific destination. We are discovering new NEOs all the time, so our list of targets will certainly expand over the coming years. One intriguing candidate is asteroid 1999AO10, which we could reach with a 2025 launch on a 150 day round trip mission, spending about 2 weeks at the asteroid.
But why would we want to visit an asteroid in the first place? Why are these space rocks such compelling destinations for humans? First, they provide an intermediate destination for human exploration, with round trip times significantly longer than the Moon but shorter than Mars. They also don’t require a high gravity landing, perhaps making them even more accessible than the Moon from a hardware development standpoint. Next, asteroids are fascinating scientifically, as evidenced by the National Academy’s endorsement of their exploration in Decadal Surveys and other reports. They are remnants of the birth of our solar system – they preserve the primitive materials from which our earth, and possibly even life, formed. Some asteroids are very rich in valuable metals, and may be important space resources. And finally, we know NEOs are important for life on Earth because they have affected our evolution through mass extinctions they have caused.
The bottom line is, NEOs represent one of only a handful of threats that could wipe out humanity. It is not a question of WHETHER we will be hit by an extinction-scale NEO in the future, but merely WHEN this will happen. Only by gaining experience operating at these objects might it be possible to someday prevent one from changing the course of humanity’s future. One issue with exploring NEOs with humans is that the U.S. has only operated around the largest NEO, with the robotic mission NEAR. The Japanese have visited another. But most of these objects are still very mysterious to us. We know very little about 1999AO10, potentially our most promising target. This is where our Exploration Precursor Robotic missions come into play. With these missions, we can explore potential candidates, and provide ground truth for our Earth-based telescopic observations of NEOs.
These are truly tangible reasons for making a NEO, one of our first destinations for humans in deep space. And I have to add, it is incredible how well Hollywood taps in to the psyche and true desires of the public, so having something appear in a movie is not necessarily a bad thing. The public is fascinated by NEOs, and I am sure they are also a little afraid, to be honest. A recent poll just completed by the Everett Group found that sixty-three percent of those who said exploring space was at least somewhat important cited protecting the Earth from collisions with comets and asteroids as a major reason for continuing that exploration. NASA has been working, and in the new budget ramps up, the activity of cataloging and characterizing NEOS. If one is going to pose a danger to Earth, we need to know about it, and by visiting one, we'll have that much better of an understanding of what it might take to mitigate potential future collisions.
A mission to a NEO will also test our deep space propulsion systems, since we're talking about 5 million miles of travel as opposed to around 239,000 to reach the Moon. They'll test our ability to orient ourselves and explore on an alien world. They'll test the habitat, radiation protection and life support systems we'll be developing for human beings in deep space. All in all, they're a tough destination. And Mars will be even tougher.
Link: Remarks by NASA Deputy Administrator Lori Garver, Center for Strategic and International Studies (CSIS), 26 April 2010
Link: Results from the Everett Group’s “Space Poll”, March 27-April 12, 2010
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