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How to Defend Earth Against an Asteroid Strike

12 points by peter123 18y ago

gojomo 18y ago
They don't mention my favorite idea: move the Earth. (I first saw a tiny blurb about this idea in a magazine, then saw it mentioned as an idea Russian scientists had considered.) Apparently if you detonate a nuke on the moon, it will eject some of the moon's mass. The resulting change to the Earth-moon system alters the Earth's orbit around the sun ever-so-slightly. However, 'ever-so-slightly' totaled over months or years means the Earth is thousands of miles from where it would have been otherwise, converting a direct-hit into a near-miss (or vice-versa!). With enough warning, this could be a preferable approach, because it's assembled from things we already know how to do (like reach the moon), rather than targeting some tiny object at an extreme distance (an all-new challenge).
- cglee 18y ago
  Have you seen "Time Machine"? There's a scenario where a moon-based mining project goes awry, causing moon fragments to fall to Earth and basically destroying all advanced civilizations. I didn't think that was remotely possible, but maybe it is. Would love to see the article you mentioned.
  - gojomo 18y ago
    Sadly, a bunch of Googling and Yahooing hasn't turned up a reference. I'd seen the first blurb in print possibly as far back as the late 80s/early 90s, perhaps in 'Chemical and Engineering News'. (Their online archives only go back to 1998.) The later followup that suggested Soviets had done similar calculations might have been early-to-mid 90s, might have been online... but unsure. Yes, the moon-mining disaster in 2002's 'Time Machine' was pretty cool. The Orlando Bloom computer that still works 800K years in the future was more far-fetched than the moon collapsing, though. Turns out both the US and USSR considered demonstration nuclear explosions on the moon before thinking better of it: The US: http://partners.nytimes.com/library/national/science/051600sci-us-nuke.html?st=cse&sq=nuke+moon+sagan&scp=1 http://partners.nytimes.com/library/national/science/051600s... The USSR: http://www.svengrahn.pp.se/histind/E3/E3orig.htm http://www.svengrahn.pp.se/histind/E3/E3orig.htm And more recently, scientists have suggested a series of other-body-flybys could move the Earth to a further orbit: http://news.bbc.co.uk/2/hi/science/nature/1154784.stm http://news.bbc.co.uk/2/hi/science/nature/1154784.stm
- endtime 18y ago
  Why is that your favorite idea? It sounds like the most potentially harmful to us, long-term, by far. I'm no ecologist but I have to imagine changing our orbit could screw up the balance of our ecosystems pretty badly.
  - gojomo 18y ago
    It's my favorite because it's unique, plausible, and thought-provoking -- not just 'blow up or deflect the asteroid' (as just about every other idea is). The essence of the idea was that it only takes a tiny, tiny change for the Earth to wind up far away from the collision location, though not necessarily any different in its average orbit. So climate/ecosystems wouldn't necessarily be affected. But now that you mention it, the second mention of the idea I saw -- ejecting moon mass to subtly change the Earth's orbit -- may have been in the context of intentional climate engineering rather than asteroid defense.
MikeCapone 18y ago
I hope this isn't considered improper, but I wrote a few things on this topic and I think I go a bit more in depth than this Wired piece. Here they are: http://michaelgr.com/2007/04/14/near-earth-objects-are-we-whistling-in-the-dark/ http://michaelgr.com/2007/04/14/near-earth-objects-are-we-wh... http://michaelgr.com/2007/10/28/deflecting-earth-bound-asteroids/ http://michaelgr.com/2007/10/28/deflecting-earth-bound-aster... http://michaelgr.com/2008/01/27/near-earth-objects-we-cant-beat-the-odds-forever/ http://michaelgr.com/2008/01/27/near-earth-objects-we-cant-b... http://michaelgr.com/2008/01/31/target-earth/ http://michaelgr.com/2008/01/31/target-earth/
endtime 18y ago
"NASA's goal is to find 90 percent of those that are one kilometer across and larger. We're at 82 percent right now, and we've only been aggressively searching at current levels for eight to 10 years. Those ones just haven't flown into view." Can anyone work out/explain how they know they're detecting 82% of them?
- jrockway 18y ago
  They've detected all of them, but they are only going to talk about 82% of them until they get more money. "Freemium research", I'll call it...
  - ramchip 18y ago
    ...I don't know, but a more serious idea would be that the mass of everything they found so far is 82% of the mass they'd expect to find according to simulations. Like all those planets they discovered because their mass had an influence on nearby bodies. Not saying this is the actual reason, just that there are reasonable ways to get a number like this...
    - endtime 18y ago
      Yeah, I was wondering about something like that too, but as they are putting constraints on the single bodies of mass I'm not sure that's sufficient.
- inerte 18y ago
  Probably they came to know about the asteroid from another source. "Oooops, Russia/China/India space agency say they saw asteroid XYZ, why didn't we?" Or some math/cosmological models say there are X asteroids floating, but they can only really observe X - 18% (which is a huge margin of error)
thwarted 18y ago
The best and most obvious defense against an asteroid strike would be not put all our eggs in one basket and diversify our planetary holdings. Colonizing other worlds seem to provide the most bang for the buck in terms of protecting both what we have and what we will achieve from catastrophic failure of the earth.
- narag 18y ago
  That's a good long-term measure. But we also need something more cheap and quick to set up right now.
  - thwarted 18y ago
    Would it really be much less expensive and take less time to build asteroid defense systems (I almost typed "missile defense systems") which require us to deal with space than just to start getting better at getting into space anyway? Especially since most, if not all, of the technologies listed in the article would be put to better use for transportation (of either humans or goods) rather than as destructive ends (but such is the folly of human nature, I suppose). Planning for an asteroid strike strikes me as fear mongering, especially without being able to do anything "unless people see the asteroid in time to plan for it". Being resigned to a fate of having to continuously defend doesn't sound good either. I'd rather consider the possibilities for mankind's future as provided by getting off this rock than wallow in the status quo that merely deflecting an asteroid would provide.

12 points by peter123 18y ago

They don't mention my favorite idea: move the Earth. (I first saw a tiny blurb about this idea in a magazine, then saw it mentioned as an idea Russian scientists had considered.) Apparently if you detonate a nuke on the moon, it will eject some of the moon's mass. The resulting change to the Earth-moon system alters the Earth's orbit around the sun ever-so-slightly. However, 'ever-so-slightly' totaled over months or years means the Earth is thousands of miles from where it would have been otherwise, converting a direct-hit into a near-miss (or vice-versa!). With enough warning, this could be a preferable approach, because it's assembled from things we already know how to do (like reach the moon), rather than targeting some tiny object at an extreme distance (an all-new challenge).

cglee 18y ago
Have you seen "Time Machine"? There's a scenario where a moon-based mining project goes awry, causing moon fragments to fall to Earth and basically destroying all advanced civilizations. I didn't think that was remotely possible, but maybe it is. Would love to see the article you mentioned.
- gojomo 18y ago
  Sadly, a bunch of Googling and Yahooing hasn't turned up a reference. I'd seen the first blurb in print possibly as far back as the late 80s/early 90s, perhaps in 'Chemical and Engineering News'. (Their online archives only go back to 1998.) The later followup that suggested Soviets had done similar calculations might have been early-to-mid 90s, might have been online... but unsure. Yes, the moon-mining disaster in 2002's 'Time Machine' was pretty cool. The Orlando Bloom computer that still works 800K years in the future was more far-fetched than the moon collapsing, though. Turns out both the US and USSR considered demonstration nuclear explosions on the moon before thinking better of it: The US: http://partners.nytimes.com/library/national/science/051600sci-us-nuke.html?st=cse&sq=nuke+moon+sagan&scp=1 http://partners.nytimes.com/library/national/science/051600s... The USSR: http://www.svengrahn.pp.se/histind/E3/E3orig.htm http://www.svengrahn.pp.se/histind/E3/E3orig.htm And more recently, scientists have suggested a series of other-body-flybys could move the Earth to a further orbit: http://news.bbc.co.uk/2/hi/science/nature/1154784.stm http://news.bbc.co.uk/2/hi/science/nature/1154784.stm
endtime 18y ago
Why is that your favorite idea? It sounds like the most potentially harmful to us, long-term, by far. I'm no ecologist but I have to imagine changing our orbit could screw up the balance of our ecosystems pretty badly.
- gojomo 18y ago
  It's my favorite because it's unique, plausible, and thought-provoking -- not just 'blow up or deflect the asteroid' (as just about every other idea is). The essence of the idea was that it only takes a tiny, tiny change for the Earth to wind up far away from the collision location, though not necessarily any different in its average orbit. So climate/ecosystems wouldn't necessarily be affected. But now that you mention it, the second mention of the idea I saw -- ejecting moon mass to subtly change the Earth's orbit -- may have been in the context of intentional climate engineering rather than asteroid defense.

MikeCapone 18y ago

I hope this isn't considered improper, but I wrote a few things on this topic and I think I go a bit more in depth than this Wired piece. Here they are: http://michaelgr.com/2007/04/14/near-earth-objects-are-we-whistling-in-the-dark/ http://michaelgr.com/2007/04/14/near-earth-objects-are-we-wh... http://michaelgr.com/2007/10/28/deflecting-earth-bound-asteroids/ http://michaelgr.com/2007/10/28/deflecting-earth-bound-aster... http://michaelgr.com/2008/01/27/near-earth-objects-we-cant-beat-the-odds-forever/ http://michaelgr.com/2008/01/27/near-earth-objects-we-cant-b... http://michaelgr.com/2008/01/31/target-earth/ http://michaelgr.com/2008/01/31/target-earth/

endtime 18y ago

"NASA's goal is to find 90 percent of those that are one kilometer across and larger. We're at 82 percent right now, and we've only been aggressively searching at current levels for eight to 10 years. Those ones just haven't flown into view." Can anyone work out/explain how they know they're detecting 82% of them?

jrockway 18y ago
They've detected all of them, but they are only going to talk about 82% of them until they get more money. "Freemium research", I'll call it...
- ramchip 18y ago
  ...I don't know, but a more serious idea would be that the mass of everything they found so far is 82% of the mass they'd expect to find according to simulations. Like all those planets they discovered because their mass had an influence on nearby bodies. Not saying this is the actual reason, just that there are reasonable ways to get a number like this...
  - endtime 18y ago
    Yeah, I was wondering about something like that too, but as they are putting constraints on the single bodies of mass I'm not sure that's sufficient.
inerte 18y ago
Probably they came to know about the asteroid from another source. "Oooops, Russia/China/India space agency say they saw asteroid XYZ, why didn't we?" Or some math/cosmological models say there are X asteroids floating, but they can only really observe X - 18% (which is a huge margin of error)

thwarted 18y ago

The best and most obvious defense against an asteroid strike would be not put all our eggs in one basket and diversify our planetary holdings. Colonizing other worlds seem to provide the most bang for the buck in terms of protecting both what we have and what we will achieve from catastrophic failure of the earth.

narag 18y ago
That's a good long-term measure. But we also need something more cheap and quick to set up right now.
- thwarted 18y ago
  Would it really be much less expensive and take less time to build asteroid defense systems (I almost typed "missile defense systems") which require us to deal with space than just to start getting better at getting into space anyway? Especially since most, if not all, of the technologies listed in the article would be put to better use for transportation (of either humans or goods) rather than as destructive ends (but such is the folly of human nature, I suppose). Planning for an asteroid strike strikes me as fear mongering, especially without being able to do anything "unless people see the asteroid in time to plan for it". Being resigned to a fate of having to continuously defend doesn't sound good either. I'd rather consider the possibilities for mankind's future as provided by getting off this rock than wallow in the status quo that merely deflecting an asteroid would provide.