What Is J002E3?

The object, named J002E3, was discovered Sept. 3, 2002 on a near earth orbit by Canadian amateur astronomer Bill Yeung, observing from El Centro, Calif.

Initially thought to be an asteroid, it has since been tentatively identified as the S-IVB third stage of the Apollo 12 Saturn V rocket (designated S-IVB-507). When the third stage of the Apollo 12 mission failed to crash on the Moon as planned (NASA used such impacts to generate ‘Moonquakes’ that could be studied by lunar seismographs to gain information on the Moon’s interior), its subsequent orbital evolution was alternatively dominated by the attraction of the Sun and Earth.

Later study discovered that the object’s spectral signature matched the white paint used on Apollo rockets. J002E3’s orbit was quite unusual, spending some time in the Sun-Earth first Lagrange point before swooping close enough to Earth to endanger operational satellites.

NASA had originally planned to direct the S-IVB into a solar orbit, but an extra long burn of the ullage motors meant that venting the remaining propellant in the tank of the S-IVB did not give the rocket stage enough energy to escape the Earth–Moon system, and instead the stage ended up in a semi-stable orbit around the Earth after passing by the Moon on November 18, 1969.
It is thought that J002E3 left Earth orbit in June 2003, and that it may return to orbit the Earth in the mid-2040s.

► Animation explanation: Computer simulation of J002E3's motion, alternating between six Earth orbits and a heliocentric orbit.
The motion of J002E3, showing how the object was captured into its chaotic orbit around the Earth by passing near the L1 point, looping around the Earth for 6 orbits, and then leaving Earth's orbit. The Sun is to the left in these animations.
► Animation link>> https://upload.wikimedia.org/wikipedia/commons/3/39/J002e3f_orbit.gif

Further Reading and References

► http://science.nasa.gov/science-news/science-at-nasa/2002/20sep_mysteryobject/

► http://www.jpl.nasa.gov/releases/2002/release_2002_178.cfm

► https://en.wikipedia.org/wiki/J002E3

► http://science.nasa.gov/science-news/science-at-nasa/2006/15mar_moonquakes/

► https://en.wikipedia.org/wiki/Perturbation_%28astronomy%29