There are whoppers out there capable of resetting civilisation. Do we have to have a small city destroyed before we design and build the technology to avert all future impacts?
What technology could avert this sort of disaster?
The USA is apparently retiring from the business of all things progressive and space-oriented, so someone else will have to take up the torch. Right now it looks like the only country with the resources and willpower is China.
I hope some states like California can pitch in and save NASA by funding it directly before it's thrown in the garbage.
I agree, though the fact still remains that most funding will go to novel (and yes, important) scientific research rather than civilization-saving (and way more important) asteroid defense.
On the importance... if human civilization discovers the precise nature of the cosmos and no one is around in 100 years capable of learning about it, does it matter?
Given the current political and social climate I think it's a lot more pragmatic to learn how to organize and preserve our knowledge such that it's as easily decoded and readily available as possible on as large a timescale as we can manage.
I'll quote one of the most insightful comments I've read on HN:
"Most of our physical tech stack is read-only executable code: there isn't a civilizational "source code" that shows from first principles how to build up to our current technology layer. For that matter, not even from first principles to turn of the 20th century technology level."
I'm not sure why you think space exploration is a progressive issue. It's fairly non-partisan. To figure out who supports space you can mostly just look at who has the contractors or NASA center in their district.
There are aspects of NASA that are more partisan, namely the planetary sciences (which, lately, many conservatives dismiss as agenda-driven climate change science). But there is also overlapping support for funding NASA and DOD/DARPA, which you certainly wouldn't consider progressive causes.
There's also no reason to think it will be 'thrown in the garbage'. NASA funding isn't what it was during the the unique political environment of the space race, but it's funding has been fairly steady since the mid-70s. Again, a steady level with no inflections due to partisan control of government.
The bigger problem is mission-specific funding uncertainty, as many of the missions NASA would like to run take 10 years or more -- too long for politicians to benefit from successes, so there is less individual incentive to fund an ambitious challenge like sending humans to Mars.
I don't think you understand how anti-science the current Republican movement is. The problem is that science often disagrees with these foregone conclusions that the party comes up with and ends up being an obstacle to their goals.
As they say, when you're a hard right-wing person reality has a left-wing bias.
Humans already have the technology - nuclear explosives, and a lot of them.
And I don't see how it's a bad time for space-oriented stuff in the USA - it hasn't been this good for years! What makes you think NASA is going to get defunded?
Nuclear weapons aren't especially useful for pushing things around. You need a sustained, directed force to make any meaningful change in trajectory.
Nuking an asteroid would likely just bust it up into smaller chunks that are still going in roughly the same direction. Instead of one threat you now have millions.
The usefulness of nuclear explosives is in their high energy-to-weight ratio. It's very easy to mount them on rockets, guide them to targets and detonate them precisely. A short burst is as good as a long push if the total force is the same, and nuclear explosives provide lots of that.
Most ideas for using nuclear explosives for asteroid redirection don't involve buryingit into the surface, but rather a "stand-off" explosion that occurs some distance from the asteroid's surface. This would massively heat that side of the asteroid and cause a layer to puff off, acting as reaction mass, and not fracturing the asteroid itself.
And if an asteroid really was blown apart into smaller fragments, that would be an improvement. Even a small relative velocity between fragments would spread them out to a much larger area than the earth's diameter, meaning that fewer would probably hit. Also, smaller meteorites are typically much less destructive than larger ones, measured by weight. It's not linear - one hundred meteors of a hundred tons each is basically harmless, but one ten thousand ton meteor can blow a chunk out of a city. Blowing an asteroid into a 'million fragments' would be a job well done.
The USA is apparently retiring from the business of all things progressive and space-oriented, so someone else will have to take up the torch. Right now it looks like the only country with the resources and willpower is China.
I hope some states like California can pitch in and save NASA by funding it directly before it's thrown in the garbage.