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Sorry it was TiO not TiO2.

Paint Confirms Earth's New Satellite Not an Asteroid
By SPACE.com Staff
posted: 07:00 am ET
18 September 2002

Astronomers have the first direct evidence that a newly discovered object orbiting Earth is debris from one of the Apollo moon launches over 30 years ago.

Carl Hergenrother and Robert Whiteley, astronomers at the Lunar and Planetary Laboratory at the University of Arizona, measured reflected light from the object Sept. 12 and 13 and say it does not look like an asteroid. In fact, it has the colors of a rocket booster, just as had been suspected.

The researchers used the Steward Observatory 61-inch telescope near Mount Bigelow in the Santa Catalina Mountains north of Tucson for observations of J002E3.

Apollo astronauts left nuclear-powered science packages on the Moon, as seen in this photo. The inset shows a close-up of the Passive Seismic Experiment deployed on Moon by Apollo 14 moonwalkers.

The rocket that might have created the junk, and a space-based view of another Apollo mission's rocket booster similar to the one that might hit the Moon next year.

The Asteroid Research Team at the Fort Bend Astronomy Club made three 30-second images of J002E3 on Sept. 10. Background stars remain fixed as the object is seen moving in an animation of the three images. Click to see it.

The mysterious object was discovered in orbit around Earth on Sept. 3 by amateur astronomer Bill Yeung. It orbits Earth about twice as far away as the Moon.

The discovery made news headlines as it could be the only satellite, other than the moon, naturally captured by Earth to enter Earth orbit. After studying the object's past motion, Paul Chodas of the NASA Jet Propulsion Laboratory (JPL) in Pasadena, Calif., concluded that the object had been orbiting the sun until April of this year, when it was captured by Earth.

Researchers have believed that J002E3's small size and unusual orbit suggest the object is no asteroid or other natural object, but a piece of man-made "space junk," possibly a piece of one of the Saturn V rockets that launched American astronauts to the moon during the Apollo program.

Hergenrother and Whiteley made photometric measurements showing that the object spins once every minute or two seconds -- more observations are needed to pin down the exact time. "Such a rapid rate of rotation is not unheard of either for an asteroid or a piece of man-made space junk, but is very consistent with each," Hergenrother said in a statement.

The University of Arizona astronomers made their definitive observations with various filters to sample the colors, or spectra, that J002E3 reflects.

"Rather than looking like a known asteroid, the colors were consistent with the spectral properties of an object covered with white Titanium oxide (TiO) paint," Hergenrother said. "The Apollo Saturn S-IVB upper stages were painted with TiO paint."

Hergenrother and Whiteley checked their observations with some professional colleagues, " a kind of informal 'peer review' just in case we were way off on things," Hergenrother said. Those key colleagues include Richard Binzel and Andy Rivken of the Massachusetts Institute of Technology. Binzel and Rivken took infrared spectra on the unique object, and those spectra "confirm that J002E3 is a dead ringer for white TiO paint," Hergenrother added.

The object is most likely a S-IVB from either Apollo 8, 10, 11, or 12, with Apollo 12 being most likely, the researchers conclude. "As Bill Yeung said, this is the first recorded observation of any object being captured into a geocentric orbit," Hergenrother said.

A JPL scientist had previously concluded the object has a 20 percent chance of hitting the Moon next year. Scientists hope to monitor that collision.