A mountain of rock and iron is hurtling towards us
from space. Apophis -- a 300-meter diameter asteroid --
is still millions of kilometers distant. But in 2029,
it will make a spectacularly close passage by our
planet. When it does, its orbit around the Sun will
be affected.

A shift of just a few hundred kilometers, and Apophis
could return in 2036 to slam into Earth, creating
widespread devastation.

Alarming news? Sure. But what's really disturbing
about the possibility of Apophis slamming into our
planet -- an impact that would unleash the energy
of 65,500 Hiroshima-sized atomic bombs -- is the
fact that no one, anywhere, knows how to track this
asteroid accurately enough right now to properly
assess its danger to Earth 30 years from now.

Which is why we must confirm, one way or another,
that there's really no chance of impact. Will
Apophis pass through the "keyhole," the small area
on its 2029 path that would cause it to hit Earth
on its next orbit in 2036? We have to find out,
because if an impact is likely to occur, we're
going to need all the time possible to plan and
implement space missions to deflect it away
from Earth.

The chance of it hitting the Earth in 2036 is 1 in 43,000 and it is classified as a Level 0 on the Torino impact hazard scale. Which means "The likelihood of a collision is zero, or is so low as to be effectively zero. Also applies to small objects such as meteors and bodies that burn up in the atmosphere as well as infrequent meteorite falls that rarely cause damage."

More info here
http://www.planetary.org/programs/projects/apophis_competition/

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Our best information indicates that, on April 13, 2029, the asteroid will pass over London at less than one tenth the distance to the Moon and 4,000 miles inside the geostationary satellite orbit. In the fading twilight on April 13, Londoners will actually be able to see Apophis in the sky. They will have to look just to the west of due south, about 45 degrees above the horizon...

April 13th 2029 is a FRIDAY!

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The closest approach of it, being at least 3402,6 km or 2114 miles, would occur the 13th of April 2036 according to the NEO database using analysis based on 2 radar delay, 5 Doppler, and 31 optical observations spanning 884.52 days between 2004-Mar-15.10789 and 2006-Aug-16.626954.

There is a 99.99780000% chance the asteroid will miss the Earth.

We'll just have to check its orbit from time to time as 2029 approaches. If there will be a collision or the chance increases significantly we'll have to find some way of pushing it aside gently but some time before 2029. If it's a rock of density 2.2 and spherical I calculate its mass to be about 31 million metric tons, about 20 times as much as all the rubble removed from the Twin Towers terror act.

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The closest approach of it, being at least 3402,6 km or 2114 miles, would occur the 13th of April 2036 according to the NEO database using analysis based on 2 radar delay, 5 Doppler, and 31 optical observations spanning 884.52 days between 2004-Mar-15.10789 and 2006-Aug-16.626954.

There is a 99.99780000% chance the asteroid will miss the Earth.

Taking these data into account, i doubt it will collide with earth. But the approach is quite close, so, are there any geostationary sattelites in Apophis way?

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U r s

Taking these data into account, i doubt it will collide with earth. But the approach is quite close, so, are there any geostationary sattelites in Apophis way?

I'm surprised we haven't recorded any lunar hits with all the NEOs out there.

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me@rescam.org

Is there not a chance that IF we did have to send rockets out to avoid it hitting us, say by exploding it into bits, wouldn't that cause many dozens of rocks from the broken asteroid to come hurtling towards the Earth? However, these bits should burn up in the atmosphere with a bit of luck. So maybe 'deflecting' it, as you said, might be a safer bet. How would they do that do you think? By exploding something NEAR to it to send it away? That would avoid the problem of many fragments coming our way, I think.
Sue.

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'No one can make you inferior without your consent.'
Eleanor Roosevelt.

Or we could use a gravitational tractor. Build a space craft with sufficent mass and use the gravitational pull between the craft and the asteriod to alter the asteriods orbit. The chance of impact as I stated earlier though is 1 in 43,000.

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Urs, the chance of Apohpis hitting a geostationary satellite is very remote because of the small asteroid, the small satellites and the vast space among them. If there were a collision I would expect that the people in the right places would see some kind of a big flash. Maybe it would be something like the penetrator that hit that comet months ago. Susan, you're right. Exploding Apophis into bits would leave both big and small bits that might be worse than letting the asteroid smack into Earth whole.

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Taking these data into account, i doubt it will collide with earth. But the approach is quite close, so, are there any geostationary sattelites in Apophis way?

I'm surprised we haven't recorded any lunar hits with all the NEOs out there.

Misfit,
I seem to remember that a few lunar collisions HAVE been noted, over the past centuries. However, the evidence would be difficult to observe, I would imagine.
There would be two reasons for this:

1) The moon, as you know, keeps one face towards us, thus effectively shielding it from most incoming objects. Of course, we would only be able to see collisions on the "light side" of the moon, or on the "limbs" at the extreme edges of the lunar disc.

2) The lack of a significant atmosphere means such objects don't burn in the atmosphere, so any visible effects would be restricted to energy given out by the actual colllision.

IF we did have to send rockets out to avoid it hitting us, say by exploding it into bits, wouldn't that cause many dozens of rocks from the broken asteroid to come hurtling towards the Earth? However, these bits should burn up in the atmosphere with a bit of luck. So maybe 'deflecting' it, as you said, might be a safer bet.

Susan,
The problem with shattering an asteroid is, as you say, that fragments would still impact Earth. Many fragments would most likely be of sufficient mass to do considerable damage. From the little I know about the composition of Apophis, it is mostly IRON and rock. Rock tends to pulverise relatively easily in the right circumstances, but enormous heat would be required to reduce the iron content into small enough fragments, probably enough to vaporise the metal. That would have to be one helluva big explosion.

Explosives cause damage by means of a pressure wave, caused by tremendous release of heat in air, rock or some other medium, so simply dropping a nuke onto, or near, the surface of Apophis would achieve nothing, as there is no material to provide a pressure wave strong enough to cause damage. Therefore, blowing up the asteroid would require the drilling of a hole deep into the interior of Apophis. A rather risky option, since the material is largely unknown, and may resist drilling. A manned mission would also be necessary, in this option.

landing a rocket motor or two, and setting them off may be the way to go. However, even this option is a hit and miss affair, as Apophis is most likely tumbling on it's axis, meaning the thrust from any rocket motor would be directed according to Apophis' attitude. Very inexact, and VERY dangerous.

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landing a rocket motor or two, and setting them off may be the way to go. However, even this option is a hit and miss affair, as Apophis is most likely tumbling on it's axis, meaning the thrust from any rocket motor would be directed according to Apophis' attitude. Very inexact, and VERY dangerous.

But the earlier we start doing something like this the less we actually have to move it. Still dangerous, but starting sooner rather than later give us a chance to correct any mistakes and would require much less power.

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But the earlier we start doing something like this the less we actually have to move it. Still dangerous, but starting sooner rather than later give us a chance to correct any mistakes and would require much less power.

Of course, you are right!
Procrastination will only make it harder.
However, according to the available information, Apophis will miss us this time. The danger will come that the slingshot effect Apophis undergoes in it's passage through Earth's gravitational field will change Apophis' orbit in such a way as to make it dangerous NEXT time round, 7 years later.
If a practical model can be designed during that 7 year gap, it will have to be applied as early as possible.
Of course, there will be a trade-off. The nearer Apophis gets, the larger any payload will have to be in order to effect sufficient deflection. A smaller payload, delivered sufficiently early will also require a large amount of fuel.
Delivering the payload early will also carry the added risk of in-flight damage to any craft sent to Apophis.
Space travel is pretty chancy stuff!
If I were in NASA or ESA, I would be pushing for a probe to be launched, which would examine Apophis before it's closest approach to Earth, so more could be learned about it's composition, whether it is tumbling, etc. That is the sort of information that would be needed before launching any "Armageddon" style mission to destroy or deflect the asteroid.

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But the earlier we start doing something like this the less we actually have to move it. Still dangerous, but starting sooner rather than later give us a chance to correct any mistakes and would require much less power.

Of course, you are right!
Procrastination will only make it harder.
If I were in NASA or ESA, I would be pushing for a probe to be launched, which would examine Apophis before it's closest approach to Earth, so more could be learned about it's composition, whether it is tumbling, etc. That is the sort of information that would be needed before launching any "Armageddon" style mission to destroy or deflect the asteroid.

Ditto

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However, it just may be that the whole thing is a valuable resource. Wouldn't it be good to put it into lunar orbit and mine metals and volatiles from it?

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However, it just may be that the whole thing is a valuable resource. Wouldn't it be good to put it into lunar orbit and mine metals and volatiles from it?

Very good idea.
Just thnk a bit about how to modify it's trajectory to get it orbiting the Moon..........
Maybe in a few hundred years?

Peter

Rail guns would be a good way to get it changed. The technology is only early days yet, but there is a university in Victoria, Australia that is looking at the technology of firing a packet of metal down a rail using ?a standing wave of generated magnetism. Apparently they can get a nail up to about 20,000 Km/hr in three meters with the launcher. If you can't throw out a lot of reaction mass, then throw out a little bit at high speed. You would only fire a packet off when its aimed at an earth orbit. Or one of the more stable Lagrange points.
Damn, I shouldn't smoke this stuff.

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Perhaps we could safely nudge Apophis into an elliptical capture orbit around the Earth and utilize it for space resources.

However, it just may be that the whole thing is a valuable resource. Wouldn't it be good to put it into lunar orbit and mine metals and volatiles from it?

It's only 300 metres across... the effort wouldn't be worth it.

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I say we use Walla's idea of a gravitational tractor and alter Aphopis's orbit. And yes, littlegreenmanfrom, i do agree that a 300m rock is not gonna give us much in terms of resources. But it will give plenty of damage when it hits :(

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I say we use Walla's idea of a gravitational tractor and alter Aphopis's orbit. And yes, littlegreenmanfrom, i do agree that a 300m rock is not gonna give us much in terms of resources. But it will give plenty of damage when it hits :(

I certainly won't argue about the damage it would do!

My vote is that a probe be sent to Apophis, to study it and learn as much as possible. The ideal time, of course, would be during it's "fly by" in 2036. This gives us 23 years to design, fund and build the probe!

The proximity of Apophis at that time would reduce the need for vast amounts of propellant, and allow, perhaps, for extra instrumentation to be sent. The possibilities would be endless in regards to experiments, observations, etc.

If the probe could be landed on the asteroid's surface, it could be easily set up to act as a radio beacon, enabling observers to track the asteroid's progress through space, and accurately plot it's orbit. This would give the longest possible advance warning of any likelihood of collision with Earth. It would also allow the transmission of data about the physical composition of the asteroid, along with the results of experiments and observations. Such data would be invaluable in deciding what to do if the asteroid is on a collision course with Earth.

Apophis could be the richest source of information for astronomers and astrophysicists yet!

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