The situation for the Hubble Space telescope is not good right now. The telescope's payload computer stopped functioning on Sunday, June 13, prompting the main computer in safe mode to restart the telescope. The telescope and its science instruments are still in operation, but science operations were suspended while the operations team tries to restore the payload computer.The operations team attempted to restart the computer but failed. They also tried to locate the problem to the components of the payload computer and switched to their backup modules. The team started investigating the Command Unit/Science Data Formatter and the Power Control Unit (PCU) on June 30th. NASA is currently testing and preparing procedures to switch to backup hardware in the event that either of these components are involved.The Science Instrument Command and data Handling (SI C&DH), which controls and coordinates the scientific instruments aboard the spacecraft, includes the payload computer. The payload computer's keep-alive signal, which allows the main computer to know everything is functioning, stopped being received by the main computer. This caused the current problems.NASA - The Hubble Space Telescope is being lifted from the cargo bay on the Space Shuttle Discovery in 1990. Credit to NASAThe operations team started investigating possible sources of the problem using different hardware pieces from the SI C&DH. The team first thought the problem was caused by a memory module that was failing. They tried multiple backups to try to change to the correct module but to no avail. The team attempted to bring the modules online again on Thursday, June 17th. However, these failed as well.They began investigating other possible causes of the shutdown, such as the Standard Interface (STINT), hardware. They began to investigate this component, which is responsible for connecting the computers Central Processing Modules (CPM) together. The team is currently investigating the Command Unit/Science Data Formatter and a power regulator in the Power Control Unit.The CU/SDF formats and sends commands and data, while the PCU ensures a steady voltage supply for the payload computers hardware. The team must go through another operation procedure to switch to backup units if either of these systems are responsible for shutting down. The procedure this time is more complicated and risky than those used last time.Because of their connection to the SI C&DH, it is necessary to switch to the backup backup CU/SDF/backup power regulator. This task was last performed by the operations team in 2008. It was also the last time that the CU/SDF failed. This was the reason for the final servicing mission of 2009 that replaced the entire SI C&DH unit.Mike Good, Astronaut, working on the Space Telescope Imaging Spectrograph Repair (STIS) during Hubble's final servicing mission in May 2009. Credit to NASAThe complexity of switching several systems to their backups means that the operations team is reviewing and updating all Hubbles procedures, commands and other information relating to the switch to backup hardware. The team will test their plans of execution next week, and then run a high-fidelity simulator.Hubble launched in 1990 and has since taken more than 1.5 million images. More than 600,000. of these were taken since 2009, when it was last serviced. These stunning images of the Universe have been used to make important discoveries about the Universe's nature. It has helped us to understand the Kuiper Belt, Trans-Neptunian Objects and Eris.It also saw the Kuiper Belt Object, (KBO), Arrokoth, the furthest object ever seen by a spacecraft in 2014. The New Horizons mission made a close approach with it on January 1st 2019. It also saw aurora in the atmospheres Jupiter, Saturn, and Jupiter's moon Ganymede. Hubble also provided the data that allowed astronomers conclude that Ganymede probably has a large saltwater sea in its interior.Hubble's contributions to the Solar System extend beyond the Solar System. They helped in the first atmospheric studies on exoplanets. They also helped to constrain the size and mass the Milky Way. The evolution of galaxies has been studied over time. Hubble also revealed the accelerating expansion in the Universe, which led to the theory Dark Energy. Hubble's 31-year, 2-month, or two-day space journey is a celebration of these and other achievements.Hubble deserves a speedy recovery. I believe I am speaking for everyone. I hope she has a few more years to live!Additional Reading:
