NASA’s Swift Powers On Third Instrument, Restarts Automated Slewing
NASA’s Neil Gehrels Swift Observatory has resumed use of its third science instrument, the Burst Alert Telescope, after the mission returned to data collection in August. Flight controllers have also allowed the spacecraft to resume automatically repointing its other telescopes to examine new high-energy flashes in the sky.
The return to normal operations follows the scaling back of a commercial mission that would have boosted Swift to a higher altitude.
Swift team members confirmed that the Burst Alert Telescope was calibrated and detecting gamma rays, the highest energy form of light, on Sept. 18. They had halted use of the instrument, which sees 16% of the sky at a time, in April to reduce power consumption. This allowed Swift’s solar panels to be best positioned to reduce drag and extend the satellite’s time in orbit ahead of the boost effort.
Usually, the flight operations team at Penn State in University Park sends a plan to Swift that tells the observatory which cosmic objects and events to observe each day. When the Burst Alert Telescope detects a flare of gamma rays, though, Swift is designed to interrupt the plan and automatically point its Ultraviolet/Optical and X-ray telescopes at the outburst.
In December 2025, the science operations team started swapping around 25% of the planned science targets for points in the sky that would minimize drag when Swift was trained on them. By February, the team had switched over to this approach entirely, eliminating Burst Alert Telescope detection slews.
The team allowed Swift to return to automated pointing on Sept. 21 after the gamma-ray instrument resumed data collection.
The return to science has caused Swift to resume its rapid sinking. It is now located around 200 miles (325 kilometers) above Earth. Below 185 miles (300 kilometers), spacecraft operations become more difficult and science observations will likely cease. The team estimates Swift will reach this threshold sometime in early to mid-October.
Monitor the Swift blog for more updates:
https://science.nasa.gov/blogs/swift
