NASA predicts when Swift will fall to Earth—but not where debris will land
NASA expects the retired Swift observatory to reenter around November 4, with an 11-hour uncertainty and some components likely to survive.
NASA’s Swift Observatory to Re-Enter Atmosphere - NASA Science
NASA’s Swift Mission Ends Ahead of Re-Entry - NASA Science
NASA’s Swift space telescope is about to crash to Earth. Where will it fall?
NASA telescope is predicted to come crashing down after failed rescue mission
Where Pieces of NASA's Swift Observatory May Crash This Week
A forecast with an 11-hour margin
NASA said Monday that its Neil Gehrels Swift Observatory is expected to reenter Earth’s atmosphere around 3:30 a.m. Eastern time on Wednesday, November 4. The U.S. Space Force prediction carries an uncertainty of 11 hours in either direction, and the agencies will keep updating it. The telescope’s nearly 22-year mission has already ended; its descent is uncontrolled.science +1
Most of the roughly 3,200-pound spacecraft is expected to burn up, but NASA says some components should survive. Where they could land depends on when Swift reenters. NASA estimates the chance of harm to anyone on Earth at about 1 in 2,100; that is an aggregate risk, not the chance for any particular person.science
Where debris could fall
NASA says surviving fragments are limited to a band between 20.6 degrees north and south latitude. Much of that band is ocean, but it also crosses populated parts of Africa, South and Southeast Asia, and Latin America. An exact impact location is not yet known.science +1
Swift’s tungsten components and parts of its mirrors could survive, the mission’s chief scientist told the Associated Press.apnews Astrophysicist Jonathan McDowell told Gizmodo that, given the spacecraft’s size and dense telescope equipment, it would not be surprising if at least 100 kilograms survived. That is an expert estimate, not a confirmed debris total.gizmodo
Why Swift is coming down
Atmospheric drag gradually pulls low-orbiting satellites downward, and increased solar activity accelerated Swift’s descent. NASA tried to extend its life with a commercial robotic mission, but Katalyst Space’s LINK spacecraft encountered problems before it could boost Swift. The observatory resumed science afterward, until it entered safe mode at an altitude of 171 miles on October 20 and controllers ended operations.science +1
The science that remains
Launched in 2004 for a planned two-year mission, Swift was built to detect gamma-ray bursts and quickly point its other instruments at their fading afterglows. It went on to observe more than 2,000 bursts and 1,400 supernovae; its data contributed to about 7,000 papers.science
NASA says it is exploring ways to respond to fleeting cosmic events with existing telescopes and other capabilities. In the meantime, the agency and Space Force will continue tracking Swift and refining the reentry forecast.science +1