CAPE CANAVERAL, Oct 31: NASA’s Swift Observatory is nearing the end of its 22-year journey in space, with the ageing telescope expected to plunge back into Earth’s atmosphere after an unsuccessful attempt to save it.
The US Space Force has predicted that the 1.5-tonne observatory could re-enter the atmosphere on or around Friday. While most of the spacecraft is expected to disintegrate during re-entry, some heavier components, including tungsten parts and sections of its mirrors, could survive the intense heat, according to NASA mission chief scientist Brad Cenko.
Any surviving debris is likely to fall into the ocean. However, parts of Africa, Australia, India, Southeast Asia, and Central and South America fall within the potential re-entry zone. The Space Force is closely monitoring the telescope’s declining orbit to track its expected descent.
The approaching end of the mission has left scientists saddened but grateful for the observatory’s remarkable scientific contributions. Launched on November 20, 2004, Swift was designed to detect some of the universe’s most energetic events, particularly gamma-ray bursts and supernovas.
John Nousek, an astronomer at Pennsylvania State University who led Swift’s control team, said scientists had anticipated the eventual end of the mission even before its launch.
He noted that objects operating in low-Earth orbit inevitably return to the planet, describing the process as a catastrophic end for the spacecraft.
Swift’s descent accelerated over the past few years due to intense solar activity, which increased atmospheric drag and gradually lowered its orbit.
In an effort to extend the telescope’s operational life, NASA hired Katalyst Space about a year ago to carry out an emergency rescue mission. The company deployed a three-armed robotic spacecraft called Link, which was launched in July.
However, the rescue operation encountered technical difficulties. The robot managed to approach Swift only within approximately 12 to 15 kilometres before the attempt was abandoned. Link subsequently re-entered Earth’s atmosphere in September.
Despite the unsuccessful rescue, Swift continued collecting scientific data and identifying gamma-ray bursts and other extremely energetic cosmic events. By late October, however, its orbit had become too low to maintain the stability required for scientific observations, forcing the mission team to shut down its systems.
Over its operational lifetime, the observatory detected more than 2,000 gamma-ray bursts and 1,400 exploding stars. It also observed numerous comets, asteroids and black holes tearing apart nearby stars.
One of Swift’s most important capabilities was its ability to rapidly change direction and focus on sudden cosmic explosions. This distinctive feature allowed astronomers to study short-lived celestial events that might otherwise have gone undetected.
NASA regarded Swift as an important early-warning observatory for major space telescopes, including Hubble and James Webb. Its alerts enabled other observatories to turn towards newly detected events and conduct more detailed investigations.
With Swift approaching the end of its mission, scientists are now examining how its capabilities can be replaced and how future observatories can build on its achievements.
Nousek expressed hope that the scientific knowledge and operational experience gained through Swift would help shape future space missions and accelerate humanity’s understanding of the universe.