Asteroid-Bashing Spacecraft Is Ready To Test An Earth-Saving Manoeuvre

[ScienceNoob]

https://www.nature.com/articles/d41586-022-03030-x

If this doesn't work are we doomed?

[1ozzy]

Ask Private James Frazer.

[ToraToraTora]

We're doomed anyway, in approx 4.5 billion years the sun will swallow the earth.

[webbo3]

I had something planned then. ^

[Old_Geezer]

We'll just move the Earth out as the sun expands in order to keep it in the Goldilocks zone.

[Old_Geezer]

Let's hope they aren't more successful than expected and move it into a collision course towards Earth.

[Rev. Green]

Will this achieve anything that a back-of-an-envelope calculation would not? (apart from paying a troop of scientists for a few years)

[Paigntonian]

Don't think they would go to all this effort and expense unless there was an imminent threat. Think we're being sold a pup.

[Zacs-Master]

It’s a test run to…..test……the potential of this type of operation.

[Paigntonian]

Zacs: Don't agree.

[jim360]

We'd be doomed anyway if a large enough asteroid headed towards us -- although the odds of that happening are fairly low, at least over short timescales. Even if this technique were shown to work in this small case, much larger asteroids would naturally require a much greater force to shift, and I'm not sure a rocket of this size would make nearly enough of a difference.

As to Rev. Green's question, I think the point is that, sure, you can use basic conservation of momentum to predict what would happen if the asteroid in question were a solid object. What I think they are testing is, instead, more the question, "does the asteroid stay in one piece after impact, or instead shatter/break down?" Or, in other words, are asteroids of this size even solid, in a meaningful sense?

I think they referenced "Armageddon" in the article, but annoyingly a better film with the same theme came out that year, in "Deep Impact", and there I think the missile-related approach failed because, rather than diverting the course, rockets either had minimal impact or merely split the giant rock into two slightly smaller, but still deadly, rocks. Granting that it's fiction, it's still an interesting and difficult question as to what happens when you try to blow things up. So it's good to test here, in a setting where thankfully our lives aren't at stake, to see how explosions or impacts affect asteroids in practice.

[Zacs-Master]

Paignton, from the article:
‘The goal is to knock the harmless space rock into a slightly different orbit to test whether humanity could do such a thing if a dangerous asteroid were ever detected heading for Earth.’

[douglas9401]

I've applied for a grant to throw golf balls at orcas to test the effectiveness of that as a method of stopping them beaching.

Updates on this essential research as they become available.

[Paigntonian]

'I know what we'll do Mr President. We'll spend tonnes of money on a threat that doesn't currently exist, just in case, long after your presidency, a threat might exist, or not'.
Biden: snoring heard.

[jim360]

As to the idea of an imminent threat, as Paigntonian suggests, that's being covered up (see, again, "Deep Impact"), I'm fairly sure that the consensus is that even quite large objects heading towards us could be missed easily. There may be one about to hit right now and literally nobody would know. Space rocks are (a) small and (b) dark, so it is quite easy to miss. Also, even with more or less total control of numerics and how Gravity works, you'd still have an inevitable uncertainty that meant that, at best, if you had something ten years out, you'd not be sure if it would hit Earth or just miss it be c.50,000 miles or so. So there wouldn't be enough confidence to regard it as a sure threat. And, finally, if such a threat existed but were being kept secret, the chances that it leaked would be immense, so the idea that this is a test run in preparation for an imminent threat is a complete non-starter.

I think one of the closer near-misses in recent years, we spotted only as it was passing Earth, rather than long enough before the closest approach for us to prepare.

[Zacs-Master]

Paignton:
1. The threat exists, hence the test.
2. Biden didn’t commission it. Trump was POTUS when it was commissioned.

[Zacs-Master]

No one said the threat was imminent.

[Paigntonian]

Jim: I'm sure you're right. This vastly expensive enterprises don't happen unless there's a real threat. The idea that politicians give a monkey's about what might happen in a thousand years is absurd.

[Paigntonian]

Zacs. Who said Biden commissioned this? I didn't.

[jim360]

// We're doomed anyway, in approx 4.5 billion years the sun will swallow the earth. //

That's way too optimistic :P Apparently, in about one billion years, the Earth wouldn't be able to support liquid water -- and in about half that, most plant life as we know it would be dead -- as the Sun's radiation output grows, so we'd be screwed long before the Earth is destroyed.

On the other hand, if humanity is around for that long, I suspect we'll have figured out a way to get to Mars at least (which may well benefit from the same process), so maybe humanity will at least outlive Earth.

[Zacs-Master]

You implied it by mentioning him.