NASA may have finally identified a problem with Hubble’s telescope systems

Hubble’s telescope systems have been hacked several times, but now it was different. Restartes did not help, and the system kept falling into safe mode when the computer operating the scientific instruments on board the telescope did not report to the main computer. At the same time, NASA quickly found out that there would be no problem in the memory and probably not even in the payload computer itself. –

–

The Payload Computer is part of the Science Instrument Command and Data Handling (SI C&DH) unit, which has another identical backup scientific computer. Both use the necessary memory, which is available to both in a total of four identical versions. Then there is also the STINT (Standard Interface), which connects the main CPM (Central Processing Module) with other components, and in addition there is also, for example, the Command Unit / Science Data Formatter (CU / SDF), which processes and sends commands and data to scientific instruments or other parts of the telescope and, conversely, formats them accordingly before sending them to Earth.

Without detailed tests, NASA could not be sure where the problem was, so it was not worthwhile to continue to headlessly test backup systems. However, the Payload Computer backup was already tested and the telescope operator collected the necessary information from these unsuccessful attempts for later analysis, which pointed towards the PCU – Power Control Unit.

The PCU is another part of the entire SI C&DH unit and, as is clear from its designation, it is simply a power supply, the purpose of which is to supply as stable 5 V as possible for the Payload Computer and its memory modules. The PCU also carries a circuit that monitors the stability of the voltage, which, if the voltage falls below or exceeds a specified limit, instructs the computer to shut down.

Now there are two options. Either the voltage regulation in the PCU is defective, or the mentioned circuit monitoring the voltage stability is defective, while NASA has so far failed in its attempts to reset the PCU used so far, so it will probably have to be written off altogether. Fortunately, the SI C&DH unit also carries a backup power supply, the switch to it has already been approved by NASA management, and this procedure will be performed today.

NASA had to take a similar step in 2008, when the above-mentioned Command Unit / Science Data Formatter (CU / SDF) module failed and a backup had to be taken. However, a year later, as part of the last service mission, the entire SI C&DH unit was replaced, which now has the necessary backups available in case of further problems. But if the PCU backup failed, it would be really bad.

Prices of related products:

–