NASA’s Neil Gehrels Swift Observatory is expected to meet a fiery end early Wednesday morning, nearly 22 years after it launched to study the most powerful explosions in the universe, reports BritPanorama.
While most of the 3,200-pound spacecraft is anticipated to burn up as it blazes through the thick inner band of Earth’s atmosphere, NASA predicts that some fragments of the vehicle will reach the ground.
“The risk of harm coming to anyone on Earth is unlikely, approximately 1 in 2,100,” NASA stated on Monday.
The agency also anticipates that Swift’s debris could land somewhere between 20.6 degrees south latitude and 20.6 degrees north latitude, roughly 1,420 miles (2,285 kilometers) below and above the equator. This zone encompasses large areas of Central and South America, Central Africa, southern India, Southeast Asia, and northern Australia, along with vast stretches of ocean.
A risky reentry
It remains uncertain when exactly Swift will make its final descent to Earth. Prediction models usually carry a margin of error of several hours. An estimate from the nonprofit Aerospace Corporation projected reentry at 5:19 a.m. ET, plus or minus two hours. A more recent U.S. Space Force prediction set a timeframe for 7:42 a.m. ET with the same margin of error.
If Swift were launched today, it would likely have to adhere to much stricter safety guidelines regarding end-of-life planning, according to The Aerospace Corporation, a federally funded research and development center. Current orbital debris mitigation standards, updated in 2019, require that “uncontrolled reentries have an expected casualty of less than 1 in 10,000,” said Parker Wishik, a spokesperson for The Aerospace Corporation.
NASA had long anticipated that Swift would need to make an unpredictable plunge back to Earth but hoped a daring rescue mission launched in July could latch onto and boost the observatory as atmospheric drag gradually pulled it from a once-stable orbit. The mission ultimately failed, and the spacecraft descended to just 171 miles (275 kilometers) above the planet before officially halting scientific data collection.
“At this point, the spacecraft was no longer able to compensate for the effects of the increased drag and entered safe mode,” NASA explained in a news release.
A team of researchers at Penn State, NASA’s partner on the project, sent the final kill-switch command to Swift on October 20.
Swift’s demise was accelerated by a rise in solar activity over the past couple of years as the sun approached the peak of its 11-year cycle in 2024. Intense flares and coronal mass ejections caused Earth’s atmosphere to expand, increasing the drag on Swift and leading scientists to predict its descent toward our planet this fall.
Arizona-based Katalyst Space Technologies orchestrated a last-ditch effort to stabilize the Swift observatory earlier this year, launching the mission within nine months. The company quickly produced a spacecraft called LINK, aiming to grapple with the telescope and restore it to a stable orbit. However, this mission failed shortly after LINK’s launch in July, as the satellite spun out of control before reaching Swift.
Another rescue attempt
As Swift’s fate was sealed, mission scientists gradually turned the telescope’s instruments back on to collect data and observations until the end. These instruments had been shut off for months to conserve power and slow the spacecraft’s descent from orbit.
The Swift Observatory, which does not have an established observational replacement in the pipeline, has functioned as an astrophysics multi-tool in low-Earth orbit since its launch in November 2004. Its design allowed rapid pivots to observe fleeting cosmic events, such as flaring black holes.
Despite the failed attempt to rescue Swift, NASA has indicated it may pursue similar lifeline-extension missions for other valuable space-based instruments. Last week, the agency issued a solicitation—formally a Request for Proposals (RFP)—to commercial companies, inquiring how they might boost, service, or otherwise prolong the life of the iconic Hubble Space Telescope.
NASA’s analysis shows a 10% chance Hubble will plunge out of orbit by 2032 and a 50% chance it will deorbit by 2033. The beloved telescope, launched in 1990, has produced some of the most recognizable images in astronomy and has significantly reshaped scientists’ understanding of the cosmos. No replacement for Hubble is expected before the 2040s, according to the RFP.
