NASA’s Rossi X-Ray Timing Explorer (RXTE) was decommissioned this month, following a productive 16-year mission focused on the workings of black holes, neutron stars and white dwarfs.

The spacecraft’s final transmissions were logged by the Goddard Space Flight Center on Jan. 4. The 7,000-lb. spacecraft is expected to re-enter the Earth’s atmosphere between 2014 and 2023, depending on the influence of solar activity.

The RXTE was honored Jan. 10 at the 219th meeting of the American Astronomical Society in Austin, Texas. The observatory’s three instruments helped to establish the existence of magnetstars, characterize rapidly spinning millisecond pulsars and confirm the frame-dragging phenomena around black holes predicted by Albert Einstein’s general theory of relativity. The probe helped to identify white dwarf stars as the source of the Milky Way’s diffuse X-ray glow.

“The spacecraft and its instruments had been showing their age, and in the end RXTE had accomplished everything we put it up there to do, and much more,” Tod Strohmayer, the RXTE project scientist, said in a statement.

Launched on Dec. 30, 1995, the spacecraft was renamed a year later for Bruno Rossi, the 20th century pioneer in X-ray astronomy from the Massachusetts Institute of Technology. Findings from the observatory served as the basis for 2,200 scientific papers and nearly 100 doctoral degrees, NASA says.