NASA’s Neil Gehrels Swift Observatory is expected to re-enter Earth’s atmosphere on Wednesday, 4 November, after its orbit could not be raised in a rescue attempt. The spacecraft can no longer steer or make observations, leaving its re-entry uncontrolled.
The US Space Force predicts that the 3,200-pound observatory will reach the atmosphere at about 3:30 a.m. EST. NASA expects most of the spacecraft to burn up, but says some components could survive. Any fragments that make it through are expected to fall within a band between 20.6 degrees north and 20.6 degrees south latitude. The agency estimates the risk of injury to anyone on Earth at about one in 2,100 and says NASA and the Space Force are monitoring the re-entry.
Launched in 2004, Swift was designed to operate for two years using three telescopes. It spent about two decades studying gamma-ray bursts, brief but intense flashes of radiation that occur roughly once a day. The observatory detected and tracked more than 2,000 of these events, which are among the most powerful explosions observed in the universe.
Swift also studied a range of other cosmic phenomena. In July, it observed a supermassive black hole far from its galaxy’s center tearing apart a star, an event known as a tidal disruption. NASA said the observatory’s work broadened scientific understanding of objects and events including active galaxies, supernovae, and X-ray flares from stars.
NASA tried to move Swift into a higher orbit last year with the help of a private space contractor, but the attempt failed after the spacecraft could not be reached. Last month, Swift was estimated to be orbiting 171 miles above Earth and was commanded to end operations ahead of its expected return.
Sources: The Guardian Science.