The Neil Gehrels Swift Observatory will not celebrate its 22nd birthday in orbit. After an attempted rescue failed, the remarkable space telescope returned to Earth in early November, less than 20 days before its launch anniversary.

The spacecraft burned in the atmosphere at 7:39 am EST, or 12:39 pm UTC, on November 4. The US Space Force confirmed its demise that afternoon, hours after the event.

Swift reentered above the North Sumatra region of Indonesia, near 3.4 degrees north latitude and 98.6 degrees east longitude. NASA said it expected most of the spacecraft to burn up, with very little reaching the ground.

Dean Sladen, Quality Manager and Aerospace Engineer at UK precision components supplier Accu Components, said the six heavy reaction wheels, lenses and mirrors were the most likely parts to survive.

“Its mask of around 52,000 tiny lead tiles will almost certainly melt. Only a handful of small, scorched fragments are expected to make it down, nothing recognisable as a telescope.”

Launched in 2004 for a mission originally planned to last two years, Swift was built to study gamma-ray bursts, described as the most powerful explosions in the universe. Its productive life ultimately stretched far beyond that initial assignment.

During its career, Swift observed more than 2,000 gamma-ray bursts and over 1,400 supernovae. It also recorded stars being torn apart by black holes during tidal disruption events.

The observatory watched active galaxies both near and far. Closer to Earth, it studied asteroids and comets, including the interstellar object comet 3I/ATLAS.

Its observations have contributed to roughly 7,000 published scientific papers. That works out to an average of about six papers for every week Swift spent in space.

“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,” Shawn Domagal-Goldman, director, Astrophysics Division at NASA Headquarters in Washington, said in a statement.

“And Swift leaves us with an extraordinary archive of multiwavelength observations that will fuel new discoveries for decades more.”

Swift originally traveled in an orbit ranging from 585 kilometers to 604 kilometers, or 364 to 375 miles, from Earth. Although the atmosphere is extremely thin at that altitude, it still produced enough drag to affect the spacecraft.

As Swift slowed, its orbits became shorter and lower. NASA eventually determined that the observatory was going to return to Earth, prompting plans for an ambitious rescue effort.

NASA gave private company Katalyst an opportunity to fly a robotic craft to Swift and attempt to raise its orbit. Because the telescope was not designed for such an operation, the mission was considered risky, and NASA was prepared for failure.

The LINK spacecraft launched on July 3, and the effort initially appeared to be progressing toward a possible rescue. The robotic craft ultimately failed, however, so no attempt to lift Swift took place.

With Swift’s fate sealed, its mission team continued gathering scientific observations until the end. The telescope had no rockets that could have been used to raise its orbit, making its reentry uncontrolled.

Sladen explained that once an object falls to around 120 kilometers, or 75 miles, its final descent generally takes only a few minutes. Solar panels and antennas typically tear away first, followed by the breakup of the main body near 78 kilometers, or 48 miles.

Tracking company Leonid Space had predicted that Swift would descend on November 4 at 12:12 pm UTC. That timing was consistent with the US Space Force prediction and fell within an uncertainty window of about two hours.

Several tracking websites continued showing Swift in orbit even after its predicted and confirmed demise. Dr Alysa Obertas, an astronomer who works in orbital dynamics, said she saw sites reporting that Swift remained about 150 kilometers, or 93 miles, above Earth.

Obertas explained that orbit predictions rely on spacecraft data processed by computers to generate orbital elements. Orbital decay and uncontrolled reentry were not reflected in many of the displayed predictions, meaning the sites were not necessarily showing Swift’s actual position.

“This means that the websites I was watching all morning weren’t showing real-time positions of Swift, but rather a prediction.”

Swift’s fall represents an enormous loss for high energy astronomy, but its scientific work did not vanish with the spacecraft. Its vast archive of observations is expected to support discoveries for decades to come.