Astronomers are marking the decommissioning of a satellite that has spent 16 years peering into black holes and neutron stars.

NASA's Rossi X-ray Timing Explorer (RXTE) helped astronomers establish the existence of highly magnetised neutron stars and collected the first evidence of the spacetime-distorting frame-dragging effect around a black hole as predicted by Einstein's general theory of relativity.

Although the data it streamed down to Earth resulted in more than 2,200 academic papers and 92 doctoral theses, RXTE and its instruments had started to show their age, according to Tod Strohmayer, RXTE project scientist at NASA's Goddard Space Flight Centre.

“In the end RXTE had accomplished everything we put it up there to do, and much more," he said.

Named after X-ray astronomy pioneer Bruno Rossi, RXTE was the first instrument to view growing millisecond pulsars, which had never been seen before. Its instruments could measure X-ray emissions in bursts of just microseconds between them and in a range from 2,000 to 250,000 electron volts. The probe's Earth orbit, which takes 90 minutes to complete, has a height of 600km.

NASA bosses decided to decommission the successful space lab after a review board last year ranked it low among other operating astrophysics missions. RXTE sent its last transmission of data to Earth on 4 January. A day later, NASA pulled the plug.

“After two days we listened to verify that none of the systems we turned off had autonomously re-activated, and we've heard nothing,” said Deborah Knapp, RXTE mission director at Goddard.

NASA boffins said that RXTE would re-enter the Earth's atmosphere and burn up somewhere “between 2014 and 2023”. ®