Will Asteroid 99942 Apophis hit Earth?

[HeeBGBz]

http://www.csmonitor.com/2005/0726/p01s04-stss.html

I just saw this report on CNN, too.

snip

"Humans live in a vast solar system where 2,000 feet seems a razor-thin distance.

Yet it's just wide enough to trigger concerns that an asteroid due to buzz Earth on April 13, 2029 may shift its orbit enough to return and strike the planet seven years later.

The concern: Within the object's range of possible fly-by distances lie a handful of gravitational "sweet spots," areas some 2,000 feet across that are also known as keyholes.

The physics may sound complex, but the potential ramifications are plain enough. If the asteroid passes through the most probable keyhole, its new orbit would send it slamming into Earth in 2036. It's unclear to some experts whether ground-based observatories alone will be able to provide enough accurate information in time to mount a mission to divert the asteroid, if that becomes necessary."

[phantom power]

1. Well, the time to shift it is now.

Start implementing the mission now, and it's reasonable to imagine nudging it's orbit enough to miss the "bad" window.

[longship]

7. Danger in moving it, too.

The orbit of this body is very precarious. But it's very, very difficult to make accurate predictions like this. What makes this asteroid worrisome in the first place is it's close interaction with earth in 2029. This will perturb the orbit into a new orbit which *may* collide with the earth. Unfortunately, we don't have enough information to figure out which way to move it to make the orbit safer. We very well may have it slamming into the earth with the new orbit.

The multiple body problem (with N > 2) is not analytically solvable. It would be highly advisable to wait until 2029 to find out the new orbit parameters before taking any action.

[phantom power]

14. There are tradeoffs to be made

the longer we wait, the better we know the orbital parameters, but waiting also requires a larger delta-v to correct the orbit, if we need to. Our space-born technology is pretty poorly developed, and we simply can't manage very large delta-v at this point.

From the article, I gather that what they want to do first is deposit a transponder on it, to get a really good bead on it's trajectory. They seem willing to wait at least that long, before attempting a course correction.

If we're going to get hit with a rock, it could be worse. It's not a slate-wiper, but it would be plenty big enough to make people take the general threat seriously.

[longship]

16. I like the transponder idea.

It would be great to get better orbital parameters. The transponder would be worthwhile. It would also give us a look at how the orbit changes over time, essential to determining whether the rock is a real danger.

Good post.

[HeeBGBz]

22. That's probably why they practiced hitting that comet

Or 'roid, whatever it was, on July 4th.

I remember when they first announced this one. They said it WAS going to hit Earth in 2029 and then they retracted the next day.

They've probably known for a while now that it is a potential very big problem.

[Ian David]

12. We could always put a small ion engine on it ASAP but not fire it yet

Start landing ion engines on it now, and then only fire them up when or if we decide we need to use them.

And if we don't actually need to move the asteroid to save the Earth, we could:

1) Use the rock as the base for a robotic observatory.

2) Eventually nudge it into a LaGrange orbit and start mining it.

3) Put it in an orbit that carries it in a continuous orbit between Earth and Mars, so we can use its "shadow" to protect manned missions to Mars from being exposed to solar radiation.

[phantom power]

15. But our schedule is so filled up with killing each other...

who's got the time for crazy stuff like colonizing the solar system?

[htuttle]

2. If we as a species owe anything to the Earth...

...it's that we should be stopping big rocks from hitting it from the sky.

It's sort of in our own interest too, you know?

[phantom power]

5. It's the least we could do.

Really, we ought to consider doing this even if the threat doesn't pan out. Cuz sooner or later, it won't be a drill, it will be the real thing. It might be nice to have tried it once or twice.

[woodsprite]

3. Yeah, but realistically,

just think what kind of shape this place will be in by then if we can't have fair elections, fix the policies and laws that have been trampled. If that's the case, maybe it'll land right smack dab in the middle of the United States of Halliburton all run by lil' Jebby Bush III and put us all out of our misery.

[comradebillyboy]

4. maybe, maybe not

but I'll be dead by then so who cares

[phantom power]

6. those of us who might still be alive care, a little bit...

:-)

[undergroundpanther]

10. Too long

Have parents not cared what they leave for future generations,

We use up resources and have kids and create problems and pass it on..We never have grown up,taken responsibility for ourselves let alone the ramifications of what we do and how it will effect future generations.
We have co-created a nightmare with the generations before us..when will we stop?

[beam me up scottie]

8. List Of The Potentially Hazardous Asteroids (PHAs)

http://cfa-www.harvard.edu/iau/lists/Dangerous.html

[CanonRay]

9. I'm starting to think we have it coming...

[havocmom]

18. LOL, see, I told ya I would enjoy reading more from you!

Ray of reality rather than sunshine. :thumbsup: for reality based thinking!

:toast:

[earthside]

11. A Distraction

This asteroid business is clearly a story put out by the White House to distract us from the Rove scandal.

[petepillow]

13. sure, why not. n/t

[iconoclastic cat]

17. If we're lucky, it will.

[Imagine My Surprise]

19. One can only hope

[Emperor_Norton_II]

20. Please tell me I'm not the only one who thought of this:

...when hearing that Earth may be in danger from something in space named Apophis?

...

...

..once a geek, always a geek..

[Caution]

21. sadly I too first thought "Why worry? SG-1 is on the case!"

[Desertrose]

23. but we've lost O'Neill

since RDA "retired"...

but there is Cameron Mitchell (aka Ben Browder)......:evilgrin:

[Igel]

24. No, one of the first things through my mind was that if

the odds increase that we'll be hit, a Stargate cult will spring up.

They will promptly equate "keyhole" (from the article) with "stargate".

And we'll be forced to infiltrate their ranks and convince them that the only right thing for them to do is congregate in the impact zone.

[Nihil]

25. No, it's easier than that ...

> And we'll be forced to infiltrate their ranks and convince them that
> the only right thing for them to do is congregate in the impact zone.

Just build a BIG church and set up a tele-evangelist to persuade the
"faithful" to be there at the right time!

:evilgrin: