NASA’s Swift Space Telescope to Make Its Fiery Return to Earth on November 4

The Neil Gehrels Swift Observatory, formerly known as the Swift Gamma-Ray Burst Explorer, has reached the final days of its mission and is expected to return to Earth in the early hours of November 4. The space telescope was launched into orbit on November 20, 2004, and now, nearly 22 years later, it is expected to disintegrate as it reenters Earth’s atmosphere on Wednesday.

NASA officially ended the Neil Gehrels Swift Observatory’s mission on October 23, after its altitude dropped below 171 miles above Earth, where increased atmospheric drag would have prevented it from consistently observing its targets. The observatory recorded its final observation on October 20, bringing an end to 22 years of service as NASA’s “first responder” to transient celestial events.

In a statement last month, Shawn Domagal-Goldman, director of NASA’s Astrophysics Division, said that Swift had provided the nation with an incredible and lasting return on investment. “It was designed for a two-year prime mission, but it remained productive for more than 10 times that duration,” Domagal-Goldman noted.

NASA expects the Neil Gehrels Swift Observatory to reenter Earth’s atmosphere on November 4 at approximately 3:30 a.m. ET.

Neil Gehrels Swift Observatory Set to Fall Back to Earth

The National Aeronautics and Space Administration (NASA) acknowledges an 11-hour window during which reentry could occur, meaning the observatory could fall during either the middle of the night or broad daylight. Although the news may sound alarming, NASA assures the public that most of the telescope is expected to burn up during reentry, with only a few components likely to reach Earth’s surface.

The location where those components could land will depend on the exact time Swift reenters the atmosphere. According to NASA, any surviving debris will be confined to an area between 20.6 degrees south latitude and 20.6 degrees north latitude. On a map, this would form a band stretching around roughly half of the Earth, just above and below the equator.

NASA estimates that the probability of anyone on Earth being harmed is extremely low, approximately 1 in 2,100, according to its official statement. To ensure everyone’s safety, NASA and the U.S. Space Force will continuously monitor the reentry and update their predictions.

Orbital Radar provides a live tracker for the Neil Gehrels Swift Observatory. At the time of publication, the spacecraft was above the Indian Ocean, approximately 350 km from Port Mathurin, Mauritius, at a latitude of 20.29° S.

The Legacy of the Neil Gehrels Swift Observatory

On October 20, the Neil Gehrels Swift Observatory reached an altitude of 171 miles, at which point the spacecraft could no longer compensate for the effects of increased atmospheric drag and entered safe mode. The operations team at Penn State University Park then sent a command to the spacecraft, effectively ending Swift’s operations and preparing it for atmospheric reentry.

“The Neil Gehrels Swift Observatory leaves behind a legacy of innovation and a treasure trove of scientific observations,” NASA stated.

Like all satellites in low Earth orbit, Swift was subject to atmospheric drag. Recent solar activity intensified this effect, causing the observatory’s altitude to decrease rapidly. In August, a high-risk, rapid-response servicing mission was completed without attempting to boost the observatory into a higher orbit. Swift subsequently resumed its scientific observations, which the team had temporarily suspended to minimize atmospheric drag and extend the spacecraft’s time in orbit while preparing for the boost mission.

The observatory has studied hundreds of astronomical phenomena and objects, including the remnants of stellar explosions, active supermassive black holes in distant galaxies, and comets within our own solar system.

“This is a sad moment at the Penn State Mission Operations Center, as we have carefully looked after Swift, managing its scientific operations, health, and safety, and responding to anomalies around the clock, every day for 22 years,” said John Nousek, Swift’s mission operations director and professor of astronomy and astrophysics at Penn State, in an email to CNET.