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Asteroid Once Seen As Dangerous Offers Chance For Close Study

Posted by CmdrTaco on from the no-relationship-to-sg1 dept.

RedEaredSlider writes "An asteroid that once was seen as a danger to the Earth may soon provide a once-in-a-century opportunity to get a close look at one — and learn more about the ones that really are a hazard. The asteroid is called Apophis. It's a near-Earth asteroid that is a type called a chondrite, essentially a stony body that has high silicate content and few metals. It is about 330 meters across, and it's due to pass the Earth in 2029."

4 of 122 comments (clear)

  1. Not too much of a difference... by sznupi · · Score: 4, Informative

    The speed, relative to Earth, during the encounter will be quite high - so a probe / lander / etc. allowing for really close study would need to get quite a kick from its rocket. And very rapidly (basically ruling out more efficient means of propulsion, those tend to have very low thrust) Probably much larger than sending it to some more optimal (regarding transfer orbits and delta-v) targets, a thing ... which we are already doing!

    If it turns to be practical, another nice target is good to have of course.

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    One that hath name thou can not otter
  2. Re:How do they know the content by sensei+moreh · · Score: 3, Informative

    Spectroscopes

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    Geology - it's not rocket science; it's rock science
  3. Re:How do they know the content by Nyeerrmm · · Score: 4, Informative

    We have a good idea of the composition of asteroids in general, from meteorites, planetary formation models, etc.

    We believe Apophis is chondritic because based on its apparent brightness and the way that brightness varies, we have a decent estimate of its size and albedo. If it had a different albedo it would indicate a different composition.

    Of course, as with all remote observations based on a lot of educated guesses, there is a chance its wrong. However, if it is its probably a pathological case we could never gotten right, and that would make it even more interesting to visit.

  4. Re:Capture it! by Covalent · · Score: 4, Informative

    Hard to do! It's speed is about 31 km/s...geosynchronous orbit is more like 3 km/s. So delta V is about 28km/s...for an asteroid with a mass of 2.7×10^10 kg, that's a kinetic energy of about 1E19 J or around 2.5 billion tons of TNT (2.5 gigatons). Yeah...that's a lot.

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    Great warrior...hrmph! Wars not make one great.