
Astronomers find Earth's first trojan asteroid - evo_9
http://arstechnica.com/science/news/2011/07/astronomers-find-earths-first-trojan-asteroid.ars
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marze
Not mentioned in the article but significant is that this find represents a
very easy asteroid to visit and return to Earth, either a manned mission or an
unmanned sample return mission.

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chime
> Due to the gravitational influence of other planets and the significant
> contribution of chaos to an asteroid’s orbit, it is impossible to accurately
> predict 2010 TK7’s behavior over more than a 250 year span, so it may not
> continue the cycle described above.

The erratic behavior might not make this as easy as it sounds.

See:
[http://blogs.discovermagazine.com/badastronomy/2011/07/27/wi...](http://blogs.discovermagazine.com/badastronomy/2011/07/27/wise-
finds-the-very-first-earth-trojan-asteroid/)

> ...As soon as I heard about this, I wondered if it would make a good target
> for exploration; since it’s not moving much relative to Earth, it wouldn’t
> take much fuel to get there. Unfortunately, the Lissajous orbit of the
> asteroid takes it well above and below the Earth’s orbital plane (as shown
> in green in this not-to-scale diagram; click to odysseyenate), making a
> rendezvous difficult.

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iwwr
There's at least another asteroid following Earth in a quasi-orbital fashion:
<http://en.wikipedia.org/wiki/3753_Cruithne>

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gcb
maybe it's my mind, but that was the worst angle possible for that animation
at the bottom!

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T-hawk
It's okay once you understand what it's doing. It's showing the asteroid's
movement in relation to Earth - from a vantage point mostly fixed relative to
Earth. The viewpoint sweeps above and below Earth's orbit to give you some
idea of what the asteroid is doing in three dimensions.

It is not showing the asteroid's path around the Sun and isn't trying to. The
asteroid's path relative to Earth is actually more relevant, for us to
calculate how to observe it and to project any possible collision.

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_THE_PLAGUE_II
"That's no moon. That's a space station."

~~~
alanh
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