KABUL (Pajhwok): NASA’s Swift space telescope, which spent nearly 22 years studying some of the most powerful energy explosions in the universe, fell out of orbit as expected on Wednesday and burned up in the Earth’s atmosphere over Indonesia, the US space agency has reported.
The fiery end of the Neil Gehrels Swift Observatory, which weighed about 1,452 kilograms, came less than three months after a rescue spacecraft failed to move the satellite into a higher orbit and extend its operational life, Reuters reported.
The US Space Force confirmed that Swift re-entered the atmosphere at 7:39am EST (1239 GMT), travelling at about 22 times the speed of sound over Indonesia’s North Sumatra province, approximately 322 kilometresnorth of the equator, according to NASA.
NASA said it expected frictional heat during re-entry to destroy most of the satellite high above the Earth’s surface, although some fragments could survive. The agency reported no damage or injuries on the ground from falling debris.
It was not immediately clear how close the telescope’s re-entry point was to Medan, the capital and largest city of North Sumatra, which has a population of about 2.5 million. The province as a whole has around 16 million residents.
The US Space Force had earlier assessed the risk to populated areas as very low, estimating the probability of anyone on Earth being harmed at one in 2,100.
Dean Sladen, an aerospace engineer at UK-based industrial parts supplier Accu Components, said before the re-entry that only a handful of small, scorched fragments were expected to reach the ground, with nothing recognisable as part of a telescope.
“Satellites this size re-enter the atmosphere regularly, and in nearly 70 years of spaceflight no one has ever been killed by falling debris,” Sladen said in an email.
He added that the risk of a re-entry accident increased over the longer term, making it increasingly important to design satellites that could return to Earth safely.
NASA’s $500 million Swift satellite was primarily designed to study gamma-ray bursts — the most intense energy explosions in the universe — using its three telescopes, which observe different wavelengths.
Since its launch in 2004, Swift had also studied hundreds of supernova explosions, black holes that tear stars apart, stellar X-ray flares, asteroids and comets. Its observations contributed to around 7,000 published scientific papers. The telescope ceased operations on October 20.
The observatory, which had no propulsion system of its own, far exceeded its planned two-year operational lifespan and had been drifting towards orbital instability for months.
In July, NASA and Arizona-based start-up Katalystlaunched a specially designed rescue spacecraft called LINK to rendezvous with Swift, attach itself to the satellite and move it into a higher, more stable orbit.
However, LINK began spinning uncontrollably shortly after reaching space. By mid-August, mission managers had abandoned the rescue effort, leaving Swift to eventually fall back to Earth.
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