NASA has a plan to fix the Neil Gehrels Swift Observatory, a space-based telescope for investigating gamma-ray bursts which suffered a mechanical issue in January and has been in safe mode since then.
Last month, the observatory was put into safe mode and science operations were suspended due to a failure of one of the spacecraft’s reaction wheels. The six reaction wheels control the spacecraft’s rotation, which allows the telescope to maintain its position accurately and continue pointing in the right direction. This is important for the telescope to be able to record data accurately. With the failure of the wheel, the observatory was placed into safe mode so that the issue could be further investigated.
In an update shared earlier this week, NASA confirmed that there had indeed been a failure in one reaction wheel, which seemed to stem from a mechanical issue. Although the team could have attempted to recover the failed wheel, they decided not to as the observatory can work using just five wheels. For now, they intend to perform testing using five wheels and reassess the situation in several weeks’ time.
“Swift can fully carry out its science mission with five wheels,” NASA wrote. “After careful analysis, the team has determined that the five-wheel configuration will minimally impact the movements necessary for Swift to make science observations. The team expects the change will slightly delay the spacecraft’s initial response time when responding to onboard gamma-ray burst triggers, but this will not impact Swift’s ability to make these observations and meet its original operational requirements.”
The next step is for the team to perform tests on configuring the spacecraft with five wheels. Once they have found a configuration they are happy with, they can upload the instructions to the spacecraft next week. After that, according to NASA, the observatory should get up and running once and start collecting science data again: “Once the new configuration is uploaded to the spacecraft and verified in orbit, the team will begin a phased return to science operations.”
