J002E3

J002E3 is the designation given to an asteroid discovered by amateur astronomer Bill Yeung on September 3, 2002 that later turned out to be the S-IVB third stage of the Apollo 12 Saturn V.

When it was first discovered it was quickly found that the object was in an orbit around Earth. Astronomers were surprised at this as the Moon is the only large object in orbit around the Earth and anything else would have been ejected long ago due to perturbations with the Earth, the Moon and the Sun.

Therefore it must have entered into Earth orbit very recently, yet there was no recently-launched spacecraft that matched the orbit of J002E3. One explanation could have been that it was a 30-metre wide piece of rock, but University of Arizona astronomers found that the object's spectrum was consistent with white titanium dioxide paint, the same paint used by NASA for the Saturn V rockets. Back-tracing its orbit showed that the object had been orbiting the Sun for 31 years and had last been in the vicinity of the Earth in 1971. This seemed to suggest that it was a part of the Apollo 14 mission but NASA knew the whereabouts of all hardware used for this mission; the third stage, for instance, was deliberately crashed into the Moon for seismic studies.

The only other explanation was that it was the S-IVB third stage for Apollo 12. 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 in November 18, 1969. The Apollo 12 S-IVB eventually vanished.

It is thought that J002E3 left Earth orbit in June, 2003, and that it may return to orbit the Earth in about 2032.

See also

• 3753 Cruithne

==Note==Also in orbit around the Earth are also so-called Kordylewski clouds which are large transient concentrations of dust at the Trojan points of the Earth-Moon system which were discovered in 1956 by the Polish astronomer Kazimierz Kordylewski.

External links

• Mystery Object Orbits Earth
• UA Astronomers Discover That Earth's Second Moon Wears Apollo Paint
• Animations of the orbit of J002E3
• Animations of the complete Earth encounter of J002E3
• Gallery of images of J002E3
• Technical information on J002E3