All the scientific instruments of the Hubble Space Telescope are back online. After an experienced worrying month of trying to get the Veteran Observatory working again, NASA approved a bold approach last week. Over the course of several days, the solution worked and the ground team was able to slowly get the telescope back completely online. NASA reported an error after Hubble’s payload computer stopped working on June 13. It was reported a month later that the Power Protection Unit’s (PCU) secondary protection circuit was receiving a voltage level higher than acceptable levels (this may be true, the fault Was meant to be somewhere else) or has deteriorated so much that it is stuck in this protection mode. Attempts to restart the PCU failed.
Most of Hubble’s hardware is double, so if anyone fails, there’s a backup. It is not ideal to move backups as you no longer have the means, but desperate times call for frustrations and the mission team planned to move everything towards the backup of the Science Instrument Command and Data Handling (SI C&DH) planned unit. Several tests were conducted to prepare this switch. They all succeeded and the space agency actually tried to keep the switch going.
Once this was successful, it was time to gradually remove scientific instruments from their safe mode configuration – an activity that has now been successfully completed. NASA Administrator Bill Nelson said in a statement, “Hubble is an icon that has given us incredible insights into the universe over the last three decades.” “I am proud of the Hubble team, from current members to former Hubble members who took the initiative to give their support and skills. Thanks to their dedication and thoughtful work, Hubble will continue his 31-year legacy and broaden our horizons with a vision of the universe.”
This is not the first time that Hubble has had such a backup – an example of which dates back to 2008. The only difference is that the entire SI C&DH was replaced in the 2009 service, to Hubble during the last space shuttle mission. If there is no space shuttle, there is no servicing mission. While this is worrying, NASA believes that Hubble is still several years ahead.