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View Full Version : Strange Asteroid 2009 BD Stalks the Earth



Fraser
2009-Jan-26, 12:00 AM
A 10 meter-wide asteroid named 2009 BD discovered earlier this month is making a slow pass of the Earth, coming within 400,000 miles of our planet. The near-Earth asteroid (NEO) poses no threat to us, but it is an oddity worth studying. Astronomers believe the rock is a rare "co-orbital asteroid" which follows the orbit [...]

More... (http://www.universetoday.com/2009/01/25/strange-asteroid-2009-bd-stalks-the-earth/)

frankuitaalst
2009-Jan-26, 06:49 PM
As time goes by more observations will become available about this coorbital body ...
Using the JPL ephemeris ( as for 26/01/2009) for this body I came up with the following animation of the orbit , starting at 01/02/2007, in a rotating frame to Earth ( the "line" at 10 'o clock )
The asteroid will make some close orbits but seems to leave us from 02/05/2011 on after a close encounter of 0.0023 AU .
http://www.orbitsimulator.com/cgi-bin/yabb/YaBB.pl?num=1175113160/190#190

KaiYeves
2009-Jan-27, 01:15 AM
Right, now how do we report this stalker? ;-)

aurora
2009-Jan-27, 05:13 PM
As I recall, there was something similar discovered several years ago, and it turned out to be an old booster rocket.

ten meters? I wonder if this is a rock, or is a leftover from a previous mission?

frankuitaalst
2009-Jan-28, 06:36 PM
As I recall, there was something similar discovered several years ago, and it turned out to be an old booster rocket.

ten meters? I wonder if this is a rock, or is a leftover from a previous mission?
Good point . Good idea to have this investigated ... At first glance the asteoid was close 50 years ago ...

frankuitaalst
2009-Jan-29, 06:58 AM
Seems as 2009BD is not man-made as it is calculated to have been close to Earth around june 19555 , given it follows the nominal path calculated by JPL ...
http://www.orbitsimulator.com/cgi-bin/yabb/YaBB.pl?num=1175113160/195#195

WalrusLike
2009-Jan-29, 08:16 AM
Seems as 2009BD is not man-made as it is calculated to have been close to Earth around june 19555 , given it follows the nominal path calculated by JPL ...
http://www.orbitsimulator.com/cgi-bin/yabb/YaBB.pl?num=1175113160/195#195

Um, er, correct me if I am wrong but if it was a man made object that boosted to its current orbit wouldn't it be erroneous to back track its orbit prior to the point that the rocket shut down? And how would you know where that was? Or whether there was more than one boost (unlikely I suspect).

I am most definitely not a rocket scientist... (is there an opposite? :confused:) so I may be talking nonsense here... happy to get educated...

frankuitaalst
2009-Jan-29, 09:21 PM
Um, er, correct me if I am wrong but if it was a man made object that boosted to its current orbit wouldn't it be erroneous to back track its orbit prior to the point that the rocket shut down? And how would you know where that was? Or whether there was more than one boost (unlikely I suspect).

I am most definitely not a rocket scientist... (is there an opposite? :confused:) so I may be talking nonsense here... happy to get educated...
Yes , I know what you mean ....
I can be manmade after all , but in this case the rocket ( launched after 1957 or 1959 ) would have to be firing far beyond the orbit of the moon , as the asteroid was far away from Earth in 1957 or 1959 .
It made it's close pass to Earth in 1955 , at a time were no spacecraft could have been launched if I remember correctly ....

WalrusLike
2009-Jan-29, 10:01 PM
...but in this case the rocket ( launched after 1957 or 1959 ) would have to be firing far beyond the orbit of the moon....

Thanks Frank(?) for clearing that up for me. These objects are pretty interesting because (and again I could be wrong) they are within our reach and may be the first targets for experimental space based resource exploitation. I look forward to hearing more in the future.

frankuitaalst
2009-Jan-29, 10:33 PM
Well , running the simulation I was hoping that the asteroid would have been close to Earth around 1959 . But this isn't the case . 1959 was the first year in which rockets were fired towards the moon I think as fo Pioneer 4 which missed the moon . The probe should be in solar orbit since then .
You're right : this type of objects ar easliy to reach for unmanned probes .

Chunky
2009-Jan-30, 09:21 AM
what did it mean by " it will shadow up for months if not years to come"

does it mean just follow?

frankuitaalst
2009-Jan-30, 04:55 PM
what did it mean by " it will shadow up for months if not years to come"

does it mean just follow?
Yes , that's what they mean .
In the meantime there' another publication here
http://www.newscientist.com/article/dn16510-dancing-asteroid-spirals-close-to-earth.html
which confirms my calculations about the close approach in 1955.