There's lots of stuff in and around Earth's orbit. There's those troublesome chunks of asteroid which NASA keeps an eye on lest they come too close to our planet. Then there's the satellite and rocket debris from the space age junk heap. It's important to know about that stuff because even if a sand grain sized piece collides with the space shuttle it could mean really bad news. NASA keeps a close eye on all these objects and all in all it's a pretty routine job. All that changed a few weeks ago when an amateur astronomer spotted an object he named J002E3.
Amateur astronomer Bill Yeung was using his telescope to gaze around the stars of the constellation Pisces when he spotted an odd object that hadn't been there the last time he looked. The object was elongated and didn't look like a chunk of asteroid. Very soon thereafter the object became the interest of NASA's Near Earth Object. NASA was fascinated by it. There are automated asteroid surveys of the skies every few weeks and the object did not show up on earlier surveys. So where did the object come from? And, what was it? NASA had a mystery on it's hands.
Further studies showed the object to be an elongated shape about sixty feet long. The object rotates in a tumbling manner every minute or so, causing the brightness to vary. NASA immediately ruled out extraterrestrial origins. If they were aliens, they were the galaxy's worst drivers! The object looked like it was a piece of spacecraft, but it didn't look like anything launched from Earth recently. NASA then began tracing it's past orbit to try and find out where (and when) the object came from.
Once enough orbital data is collected it's possible to plot past and future orbits of J002E3. Scientists soon found out that the object had indeed come from Earth, in about 1971. After a brief Earth orbit, the object moved to a solar orbit for the next about 30 years and just a few months ago was snatched back by it's planet of origin.
Once we knew when the object went into orbit, it was possible to make a good educated guess as to what the object was. The Apollo program was in full stride in 1971 and that object fit the description of a chunk of the third stage of the giant Saturn V rocket. The likelihood of it being a chunk of Saturn rocket was increased more so when NASA did a spectroscopic study of the colours of J002E3. These test results matched perfectly the titanium dioxide paint used on the Apollo rockets. Now the only question was: which Apollo mission did J002E3 come from?
NASA keeps track of every piece of everything it ever launched so it was possible to figure out just which Apollo rocket our object came from. The most obvious guess was that it was from Apollo 14, launched in January of 1971. Unfortunately this was immediately ruled out because every piece of that entire rocket is accounted for. The most likely culprit is Apollo 12, launched in 1969. When it came time to jettison the third stage fuel tank and rocket motor there was a little glitch. It was meant to enter a Sun centered orbit but that final burn lasted too long and the tank went into a barely stable Earth-Moon orbit. That orbit is very similar to the one J002E3 is in right now. Then, at some point, the tank disappeared. NASA theorized that gravitational tugs from the Sun eventually pulled the tank into a solar orbit where it stayed for the next three decades. No one gave it much more thought. It appears however, that this remnant from the Apollo era has come back to visit, if only for a short while. Sometime in 2002, the object was recaptured by Earth's gravity and pulled back into it's original orbit. How long will it hang around? Right now it looks like J002E3 will remain in an Earth-Moon orbit until June of 2003, where it will again leave Earth's orbit and resume it's trek around the Sun. And, it's just as possible that in about 31 years, the tank may return for another Earthly visit!
Copyright © 2002 Kathy A. Miles and Charles F. Peters II