NASA’s Neil Gehrels Swift Observatory concluded its 22-year mission on November 4, 2026, following an uncontrolled reentry into Earth’s atmosphere over northern Sumatra.
The 1,450-kilogram telescope, which entered the atmosphere at 7:39 a.m. EST, was expected to burn up during its descent, with officials estimating the risk of surviving debris causing harm at 1 in 2,100.
“This was designed to be a two-year mission,” said astrophysicist S. Bradley Cenko of NASA's Goddard Space Flight Center. Launched in November 2004, the spacecraft was built to detect and pinpoint gamma-ray bursts, the most powerful explosions in the universe.
Its name reflected its unique agility: the observatory could swing its suite of instruments toward a burst within about a minute of detection, allowing it to capture data before the light faded.
Space Force reports SWIFT reentered at 1239 UTC Nov 4 over 99 deg E, 3 deg N over Northern Sumatra
“Swift needed to detect and locate gamma-ray bursts, communicate their position to other observatories, and then swing its telescopes around to image the burst locations before their afterglows faded out,” said S. Bradley Cenko, the mission’s principal investigator at NASA’s Goddard Space Flight Center, in an October 23 statement.
A Failed Rescue Attempt
The observatory’s orbit had been steadily decaying due to atmospheric drag, a process exacerbated by high solar activity in recent years. Because Swift lacked onboard thrusters to adjust its altitude, NASA contracted the Arizona-based firm Katalyst Space Technologies in September 2025 to attempt a rescue. The company developed a robotic servicing spacecraft called LINK, designed to grapple the telescope and boost it into a higher orbit.
Likely reentry of @NASA's #Swift observatory over Sumatra & Malaysia at 12:39 UTC today. https://t.co/yLCfhics3U
The LINK spacecraft launched on July 3, but suffered propulsion and orientation issues approximately three weeks later. While the rescue craft successfully approached within 7.5 to 9.3 miles of the observatory and captured photographs, it could not perform the boost. LINK eventually fell back to Earth in September.
“From the beginning, this was a high-risk, high-reward mission,” said Shawn Domagal-Goldman, director of the Astrophysics Division at NASA Headquarters, in a statement on September 25.
Scientific Legacy
Throughout its career, which included a 2018 renaming to honor its first principal investigator, Neil Gehrels, the telescope observed more than 2,000 gamma-ray bursts and 1,400 supernovae. Its observations also extended to black holes, comets, and asteroids, contributing to approximately 7,000 published scientific papers.
“Swift delivered an incredible, lasting return on investment for the nation, designed for a two-year primary mission but productive for more than 10 times as long,” said Domagal-Goldman.
The observatory gathered its final scientific data on October 20. According to NASA officials, the mission concluded without a replacement for the telescope’s unique, rapid-response capabilities.
