Swift Observatory science mission ends before expected reentry

The Neil Gehrels Swift Observatory has ended its science mission. The spacecraft is now less than 275 kilometers above Earth's surface, where stronger atmospheric drag stops its telescopes from holding steady on targets. It is anticipated to return to Earth's atmosphere within a few weeks.

The observatory is flying less than 275 kilometers above Earth's surface. At that altitude, increased atmospheric drag keeps its telescopes from pointing steadily at astronomical targets. Its science mission has ended.

Swift is anticipated to return to Earth's atmosphere within a few weeks.

The spacecraft's vehicle specification was 2 years, and it remained productive for more than 10 times as long.

Swift observed more than 2,000 gamma-ray bursts and studied more than 1,400 supernova explosions. Its data contributed to about 7,000 published scientific papers.

The observatory carried co-aligned optical/ultraviolet and X-ray telescopes. It could command target-of-opportunity observations in as little as a few minutes and observe up to 75 independent targets a day. It also watched stars torn apart by black holes, tracked active galaxies, performed an all-sky X-ray survey, and examined asteroids and comets.

The mission's end removes a rapid-response, multiwavelength observatory from NASA's existing space telescope fleet. Its low-altitude drag issue shows why orbit height can constrain steady observations. NASA is exploring the ability to use and augment its existing space telescope fleet.

Swift is anticipated to return to Earth's atmosphere within a few weeks.