NASA has ended the science mission of its Swift space telescope after nearly 22 years, and the spacecraft is now falling back toward Earth. Swift made its final observation on 20 October, and NASA said it is expected to re-enter the atmosphere in the next few weeks.
The end came because Swift had sunk to less than 171 miles above Earth, where atmospheric drag stopped its telescopes from holding steady on their targets. After the spacecraft slipped into safe mode, ground controllers sent a command that effectively ended operations to prepare it for re-entry. Swift carried no propulsion system of its own, so nothing on board could push it back to a higher orbit.
A rescue attempt also fell short. NASA hired Arizona firm Katalyst Space Technologies to send a servicing spacecraft called LINK to grab Swift and lift it higher. LINK ran into propulsion and attitude control problems weeks after its July launch and could not complete the rendezvous, though it did approach within a few miles of the telescope.
Swift launched on 20 November 2004 on a mission planned to last two years. It went on to observe more than 2,000 gamma-ray bursts and more than 1,400 supernovae, and it carried out an all-sky X-ray survey. NASA said the mission’s roughly 12-terabyte archive remains open to researchers.
Source: The Register
