NASA’s Swift Observatory made its final observation on Oct. 20, when atmospheric drag pulled it below 171 miles, and the agency expects the spacecraft to reenter the atmosphere within weeks, NASA said. NASA tried to save Swift with a commercial spacecraft built in about a year, and that attempt failed. Swift stopped pointed science from mid-February to late August to hold its altitude, and the rescue never grabbed it. The six months of lost science bought time for a boost that did not happen.
What Swift Observed in 22 Years
Swift launched on Nov. 20, 2004. NASA renamed it in 2018 for Neil Gehrels, its first principal investigator. In that time it observed more than 2,000 gamma-ray bursts and more than 1,400 supernova explosions, and its data contributed to about 7,000 published papers. Two thousand bursts over 22 years is at least 90 a year, a calculation from NASA’s count and the mission’s length.
In May 2005, Swift detected GRB 050509B, a short burst that lasted 0.03 seconds, and captured 11 X-ray photons from its afterglow. NASA calls it the first short burst with a detected afterglow, and it supported the theory that short bursts come from neutron star mergers. S. Bradley Cenko, the mission’s principal investigator at NASA’s Goddard Space Flight Center, said, “Swift was designed as a satellite dedicated to studying gamma-ray bursts.” Shawn Domagal-Goldman, director of NASA’s Astrophysics Division, said Swift delivered an incredible, lasting return on investment for the nation.
How the Katalyst Rescue Failed
NASA contracted Katalyst Space of Flagstaff, Arizona, in September 2025 to design, build and launch a servicing spacecraft called LINK within about a year. LINK launched in July on a Northrop Grumman Pegasus XL rocket from Kwajalein Atoll in the Marshall Islands. After launch it lost communications intermittently and had trouble controlling its orientation.
NASA ended its involvement on Sept. 3, and LINK reentered the atmosphere on Sept. 25. It ran demonstrations of its xenon-powered propulsion system and three robotic arms instead of boosting Swift. Domagal-Goldman said in September that “this was a high-risk, high-reward mission,” according to NASA’s lessons-learned account. Katalyst CEO Ghonhee Lee said in the same account that the company went from concept to launch in less than a year.
Why Swift Fell Faster This Fall
Swift resumed observations in late August and observed hundreds of targets, including stellar explosion remnants, active supermassive black holes and comets, according to NASA’s mission blog. Resuming observations increased drag, and Swift again began to descend quickly. On Oct. 20 it reached 275 kilometers, could no longer offset the drag and entered safe mode. That is less than two months of renewed science, a calculation from NASA’s dates.
The operations team at Penn State then sent a command that ended operations and prepared the spacecraft for reentry. NASA said it will look for new ways to respond quickly to cosmic events using current missions. The Swift archive holds nearly 22 years of data, including more than 1.5 million images from its Ultraviolet/Optical Telescope, about 12 terabytes in all, and it is publicly available.
