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Small Asteroid Making 400,000 Mile Pass By Earth
AtariKee writes "Universe Today is reporting that a small 10m asteroid, discovered earlier this month and named 2009 BD, is passing within 400,000 miles of Earth. Although the asteroid poses no threat to the planet, the site reports that the asteroid is still very interesting, as it may be a rare co-orbital asteroid (as in, shares the same orbit as Earth)."
since the asteroid is coorbital, it's a little misleading to say that it's "passing" within 400,000 miles. what's really interesting is that it will be at more or less that same distance for many months, suggesting that it and earth share a common history.
according to this java simulation of the object's orbit, it won't be this close again until about 2100.
3753 Cruithne is in a Earth resonance orbit and is the first asteroid called "Earth's second moon". I don't know how many we are supposed to have now, but with this one, it is at least 3.
There are plenty of larger NEOs that are energetically easy to get to. In fact, there are quite a number that the Apollo spacecraft could have reached and returned from, and there were plans to do this in the late 1960's (using the Saturn V 3rd stage as living quarters in route, and replacing the LEM with provisions), but neither LBJ nor Nixon was really interested in manned exploration beyond the Moon. I have a feeling that JFK would have gone for this, though, as well as for the manned Venus orbiter plans using the same technology.
Well 640 000 km is, in cosmic terms, the same lane : it's only a little further out than the moon (at 400 000 km).
Think of the Earth/Moon as a car and the asteroid as a moped lane-splitting.
*Landing an object on an asteroid is neither cheap nor convenient...even a robotic device is difficult. *
Yes, but it has already been done:
http://en.wikipedia.org/wiki/Hayabusa
In fact, Hayabusa wasn't supposed to actually land, but it did, for about 30 minutes. It may have a sample of the asteroid that it is bringing back in 2010, just in time for a re-issue of the Late Michael Crichton's Andromeda Strain.
The asteroid was not destroyed by the landing....just like the comet that was hit by a space probe did not disintegrate either:
http://www.space.com/missionlaunches/050704_deepimpact_success.html
"Next to impossible": I do not think this means what you think it means.
Most asteroids are most likely actually just big piles of smaller material. They have very little structural integrity. If you tried to apply a force to one 'spot' on the asteroid the results would be at best unpredictable. Material would shift around, you might even just sort of push through it.
Another related problem is that you need to push against the asteroid THROUGH its center of mass. If that center of mass is not fixed, then you can't really do that.
Beyond that, even if the asteroid is a solid chunk of rock, you still have to despin it before you can push it, thus the whole operation becomes a lot harder, plus if it IS a rubble pile, then you may not even be able to despin it or it would be pretty hard to do so.
A gravity tractor on the other hand suffers none of these disadvantages. All parts of the asteroid are going to be attracted to the tractor. It may STILL be somewhat complicated, but probably less so. In any event we won't really know until we try.
Finally, what difference does it really make how fast you accelerate the asteroid? The point would be to put it on the desired course. Doesn't really matter if the mission is 1 hour long or 10 years as long as you get the results you want.
"Malo periculosam, libertatem quam quietam servitutem." -- Jefferson
Suddenly my whole life makes sense. Thanks.
Congratulations to "the most redundant explanation of a joke" award of the year. (-:
(Really, it was hinted at by the GGGP, literally spelled out by the GGP and GP and then thoroughly explained by you... geez...)
From Wikipedia: "There [must be] no other bodies of comparable size other than its own satellites" in a body's orbit for that body to be classified as a planet. Give the IAU some credit; they wouldn't make a definition that demoted Earth.
There was a planned manned Venus mission using Apollo technology. It would have been a fly-by, with only a few hours of time near Venus and over a year of travel time for three men. Other than to say we did it, there wasn't much of a point of doing it instead of unmanned probes, which is likely why it got cancelled.
http://en.wikipedia.org/wiki/Manned_Venus_Flyby