On November 2, The Aerospace Corporation’s listing forecast that NASA’s Neil Gehrels Swift Observatory would reenter on November 4, 2026, at 09:30 UTC, with an uncertainty of ±26 hours. NASA says Swift made its final observation on October 20, below 275 kilometers, where atmospheric drag prevented steady tracking. NASA announced the end of science operations on October 23. The Aerospace Corporation’s reentry listing NASA’s mission-end notice
Swift could follow a gamma-ray burst in about a minute
Swift was built to detect gamma-ray bursts, brief, powerful outbursts, and quickly observe them at other wavelengths. Its Burst Alert Telescope detected the gamma rays; the X-Ray Telescope and Ultraviolet/Optical Telescope provided follow-up observations. NASA says the typical sequence of detecting and locating a burst, relaying its position, and turning Swift’s telescopes toward it took about a minute.
Swift’s final campaign included a distant burst
Science News reported that the final observing campaign included technical checks, observations of Earth’s atmosphere at low altitude, a comet, and a distant, unusually energetic gamma-ray burst in late September. That burst was one of the campaign’s reported observations.
NASA’s public archive holds nearly 22 years of observations
NASA says the public archive contains nearly 22 years of brightness measurements and multiwavelength spectra, more than 1.5 million images from the Ultraviolet/Optical Telescope, and about 12 terabytes of data. NASA also credits Swift with observing more than 2,000 gamma-ray bursts and more than 1,400 supernovae; its data contributed to about 7,000 published scientific papers.
NASA is exploring whether existing space telescopes, commercial fast-to-orbit capabilities, or new missions could support rapid-response observations after Swift.
