Posted on 04/17/2007 4:41:52 PM PDT by Lonesome in Massachussets
Last September, when a tiny asteroid drifted into Earth’s vicinity, our planet’s gravity captured it. The meter-size object, designated 6R10DB9, is now making its third wide swing around Earth. It was quite faint, magnitude 19.3, when discovered September 14th with the 0.68-meter (27-inch) Schmidt telescope of the Catalina Sky Survey in Arizona, and it won’t get much brighter than that.
“Certainly 6R10DB9, with a geocentric eccentricity less than 1, is currently orbiting the Earth ,” says Gareth V. Williams of the Minor Planet Center, “although it will leave the Earth-Moon system after next June’s perigee.” Williams’s calculations show that prior to capture 6R10DB9 was in a low-inclination orbit around the Sun with a period of about 11 months. That’s typical of the paths followed by spent rocket boosters left over from space missions of the 1960s and 70s.
But if 6R10DB9 is the hollow shell of a spent spacecraft, it would be vulnerable to solar radiation pressure and exhibit noticeable changes in its orbit. Bill J. Gray of Project Pluto has analyzed 111 positional measurements made at eight observatories, including those of amateur astronomers James McGaha in Tucson, Arizona, and Peter Birtwhistle near Swindon, England. Gray finds that 6R10DB9 is behaving more like a rocky body than space junk. “I hate to say this, because it seems so implausible,” Gray comments, “but this looks a heck of a lot like a natural object.”
Still, Alan W. Harris (Space Science Institute) sounds a cautionary note. “Claiming some bit of fluff in a temporary looping orbit to be a ‘satellite,’ with all the baggage that term carries, is mere hype,” he warns. “To find a natural body in a stable Earth orbit would be a real coup. About the only place it could come from is the Moon.”
When 6R10DB9 makes its final and closest pass in June, “threading the needle” and dipping just inside the Moon’s orbit, astronomers will get their best view of it for years to come. Spectroscopic studies with large telescopes, for example, could help to reveal its true nature.
When Earth is viewed from the direction of the constellation Aries, asteroid 6R10DB9 is seen drifting up to our planet, making three complete loops, and then meandering off again. To help in visualizing the trajectory, parts of the path closer to the observer have been made “brighter.” The four dates nearest Earth are those of successive perigees. This plot is based on an ephemeris generated by the Jet Propulsion Laboratory’s Horizons software. S&T: Gregg Dinderman
le kewl!
Cruithne never has a geocentric eccentricy less than one, so it’s not actually in orbit around the Earth. It is in an odd sort of resonance with the Earth. Check out the Wikipedia article. http://en.wikipedia.org/wiki/3753_Cruithne
I knew that, but thought it was kinda fun info in need of getting shared anyway. :o)
NORAD can track objects the size of a .22 cal bullet in orbit.
Good work! Thanks!
So what ever became of J002E3?
Is it or is it not a moon?
I had a friend in college that used to say to me “You’re a veritable cesspool or useless knowledge.”
Maybe God doesn’t play dice, but it sure looks like he plays Spirograph.
Occam would be impressed by your thinking. Not necessarily positively.
Of course, if the observations are accurate enough for a terrestial observer to rule out an expended rocket body based on the reaction to radiation pressure, the aliens would have to possess an extremely subtle grasp of dynamics - and anticipate the capabilities of terrestial observers - to mask their mission that well.
University of Arizona astronomers found that the object’s electromagnetic spectrum was consistent with white titanium dioxide paint, the same paint used by NASA for the Saturn V rockets. *snip* It is thought that J002E3 left Earth orbit in June, 2003, and that it may return to orbit the Earth in about 2032.
http://en.wikipedia.org/wiki/J002E3
Meanwhile over at the Near Earth Object Program...
http://neo.jpl.nasa.gov/j002e3a.html
More simply, I’ve no idea. LOL
LOL Nice of you to consider him/her to be a friend after that assessment. ;o)
I suck at trivia games, cuz they never use any of the stuff that I inadvertently keep in my mental collection. Mathematical astronomy sounds quite specialized, while I’m talking about something a bit more random.
He was a very good friend may God rest his soul.
And God willing he will be again.
If you hadn’t asked for more info on J002E3, I wouldna looked. I’ve been having a lot of fun watching all of the paths on the “NEO Earth Close Approaches” page.
Sorry to hear your friend is no longer with us & I’ve little doubt about you meeting up with him again.
I could never understand how anyone can study “math”. I want to solve problems. In order to solve a problem I may have to learn some math or physics, so that’s ok.
Finding an interest and digging into it is the way I learn. Almost everything interests me. (Unlike Jean Francois Kerry, I am not intrigued by rap music, for instance.)
I do ok in trivial games, in part because I’m a game player (poker, monopoly, bridge, chess, football, basketball...) and I learn how to “game” the answers. That’s really important in Jeopardy or Trivial Pursuit, for instance.
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