“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 Shawn Domagal-Goldman, director of the Astrophysics Division at NASA Headquarters in Washington, after the space agency announced that the Neil Gehrels Swift Observatory ended its science mission. The satellite is expected to re-enter Earth’s atmosphere in the coming weeks.
Orbital Decay Forces Mission End
NASA shut down the telescope’s science operations on a Tuesday after the observatory fell too low in its orbit to continue taking reliable measurements of the cosmos, according to Live Science. As of that week, the satellite was orbiting about 171 miles above Earth’s surface. The increasingly low orbit and greater atmospheric drag forced NASA to pull the plug because the observatory could no longer steadily observe astronomical targets.
Live Science noted that the spacecraft became the latest victim of intense solar activity, which increases atmospheric drag on satellites and makes it harder for them to stay aloft. The final operational blow arrived in August when a private spacecraft mission to boost Swift’s orbit failed. Hardware malfunctions doomed that rescue attempt, and the rescue craft burned up in the atmosphere. Tracking units from the U.S. Space Force projected the observatory’s uncontrolled plunge would occur on or around Friday, bringing an end to the 1 1/2-ton platform’s time in orbit.
Two Decades of Cosmic Discoveries
The observatory launched in November 2004 on a primary mission scheduled for just two years, according to Live Science. It ultimately survived for 22 years. S. Bradley Cenko, the mission’s principal investigator at NASA’s Goddard Space Flight Center, explained to Live Science that the hardware was built specifically to track gamma-ray bursts that came and went too quickly for large telescopes to target.
During its extended lifespan, Swift collected more than 1.5 million images and generated over 12 terabytes of scientific data, contributing findings to approximately 7,000 research papers. Its multiwavelength capabilities allowed it to track supernovas, black-hole-related stellar destruction, comets, asteroids, and an all-sky X-ray survey.
Friction Heat Vaporizes Most Spacecraft Debris During Re-Entry
As the spacecraft descends deeper into the atmosphere, intense friction heat will cause it to begin burning up. Any remaining debris is expected to be minimal because most satellites break apart and largely disintegrate during re-entry. Orbital speeds generate friction hot enough to vaporize high-density aerospace alloys, ensuring that the vast majority of the hardware burns into ash long before reaching the ground.
Frequently Asked Questions About the Swift Observatory Re-entry
What altitude was the Swift Observatory at when operations ended?
The satellite was orbiting at approximately 171 miles above Earth’s surface when NASA shut down its science operations in October.
How much did the Swift Observatory weigh during its descent?
According to U.S. Space Force tracking data, the spacecraft had a total mass of roughly 1 1/2 tons.
What caused the failure of the mission’s orbit-boosting attempt?
Live Science reported that a private spacecraft mission intended to boost Swift’s orbit failed in August due to a series of hardware malfunctions, causing the rescue craft to burn up in the atmosphere instead.
More on Space Force
Related reading