NASA continues to work on a problem that has suspended the scientific operations of the Hubble Space Telescope. After detecting the loss of a specific data synchronization message, the scientific instrument entered the safe mode configuration on October 25.
The Hubble team is focusing on isolating problems in the hardware that controls the instrument and is part of the scientific instrument command and data management unit. Specifically, the team is analyzing the circuit of the control unit, which generates synchronization messages and transmits them to the instrument.
While analyzing the control unit, the team is working to determine possible solutions to the problem. These include possible changes to the instrument flight software, which can check for these missing messages and compensate them without putting the instruments in safe mode. These workarounds will first be verified using a ground simulator to ensure that they work as planned.
On the weekend of October 30th, the team is going to turn on some equipment of the near-infrared camera and multi-target spectrometer (NICMOS) to collect data about this problem, so that the team can determine the cause of the problem frequently. NICMOS was installed in 1997 and has been inactive since the wide-angle camera 3 started operation in 2010. NICMOS allows teams to use instruments to collect information about these missing messages, while shutting down active instruments as a safety measure. Since NICMOS was restored on November 1, no other sync messages were lost.
The team is now taking steps to restore Hubble’s Advanced Survey Camera (ACS) instrument from safe mode and will begin using it to collect scientific data early next week. The team will make a decision on Sunday after analyzing the latest data. If you view the lost messages before that date, the decision to activate ACS will also be reviewed. The team is proceeding cautiously to ensure instrument safety and avoid additional stress on the hardware. Therefore, only ACS will be used for this capacity next week. ACS was chosen as the first recovery tool because it has the fewest complications when losing messages.
In the next week, the team will continue to analyze the control unit design drawings and data related to the missing messages to determine the possible cause of this problem. They will also investigate possible changes to the instrument software that can help solve this problem. Once the team better understands the frequency of problems and determines the time required to implement possible software changes, they will discuss plans to return other instruments to scientific operation.