Don't Look Up: After spending more than 20 years in space, the Neil Gehrels Swift Observatory is now expected to undergo a "catastrophic" reentry into Earth's atmosphere. Most of the telescope should burn up during the process, but a few surviving pieces could eventually reach the ground and pose a risk to people.
The Swift Observatory could plunge back to Earth as early as this Friday, US authorities said. The telescope is expected to undergo an uncontrolled reentry after NASA and Katalyst Space Technologies tried – and failed – to correct the spacecraft's orbit using a robotic device in September.
According to US Space Force predictions, the Swift Observatory should burn up in the atmosphere during reentry. A few components, including tungsten-made parts and mirrors, might survive the atmospheric plunge and eventually reach the ground.
The Space Force is tracking Swift's orbit to determine where these components could land. Parts of Africa, Australia, India, Southeast Asia, Central America, and South America could potentially be affected. Most likely, however, the surviving debris will end up in the ocean.
According to John Nousek, an astronomer at Pennsylvania State University who is in charge of Swift's control team, the aging telescope is going down with a bang.
"We've known this day would come since before Swift was launched. At least in low-Earth orbit, what goes up must come down," Nousek said.
The Neil Gehrels Swift Observatory launched on November 20, 2004, aboard a Delta II rocket. Led by astrophysicist Neil Gehrels, the mission was tasked with studying extremely energetic events known as gamma-ray bursts. Eventually, the orbiting observatory was also used as a "general-purpose" telescope to observe transient events across other parts of the electromagnetic spectrum.
Despite its catastrophic end, Swift was an extremely successful mission. Its primary mission was expected to last just two years, but the telescope kept operating for 21 years and 11 months. Over the past few years, the spacecraft's orbit had been affected by the expansion of Earth's atmosphere caused by increased solar activity.
NASA and Katalyst launched the "Swift boost mission" in July, sending a robotic probe to try to correct Swift's deteriorating orbit. The mission failed, and the probe returned to Earth in September 2026.
Like other legendary space observatories, including Hubble and the James Webb Space Telescope, Swift made major contributions to astrophysics research. The telescope observed more than 2,000 gamma-ray bursts, 1,400 exploding stars, as well as comets, asteroids, and black holes.