Engineers from NASA are attempting to repair the Hubble Space Telescope, which was shut down on June 13 due to an issue with the payload computer on board.
NASA reported that their engineers were unable to restart the computer — or its backup — after a month of trying, so the Hubble crew will switch to an alternative power unit on Thursday. According to NASA, restoring the observatory to normal operations will take several days if it is successful.
For more than 30 years, the Hubble Telescope has revolutionized our understanding of the universe. It detected Pluto's moons and demonstrated that nearly every galaxy has a supermassive black hole at its centre.
It was also helpful in the discovery of dark matter, an enigmatic, intangible substance.
Hubble's scientific instruments are controlled and coordinated by the payload computer, which is a NASA Standard Spacecraft Computer-1, or NSSC-1, system. The data collected by the computer is also analysed and manipulated by the computer's programmes.
The Power Control Unit, or PCU, which maintains a consistent power supply to the payload computer, is thought to be the source of the problem, according to NASA engineers. The PCU is contained in the Science Instrument Command and Data Handling (SI C&DH) unit, together with the payload computer.
"The team's analysis suggests that either the voltage level from the regulator is outside of acceptable levels (thereby tripping the secondary protection circuit), or the secondary protection circuit has degraded over time and is stuck in this inhibit state," according to the NASA statement.
The telescope and scientific instruments are still "healthy and in a safe configuration," according to the announcement.
The Hubble Space Telescope, which orbits 340 miles above the surface of the Earth, hasn't always worked perfectly. According to NASA, another portion of the SI C&DH unit failed in 2008, prompting a similar repair. After a servicing flight in 2009, the entire SI C&DH unit was replaced.
Hubble was serviced five times by the Space Shuttle. The most recent mission was in 2009, and with the shuttle's decommissioning, NASA has no way of sending humans to the space telescope for repairs.
Hubble will be replaced in the near future. The James Webb Space Telescope will be launched by NASA later this year. The big infrared telescope appears to be on track to become the universe's next great detective.
But, according to Don Lincoln, a veteran physicist at the Fermi National Accelerator Laboratory, it's too soon to give up on Hubble.
"Astronomers have relied on the instrument for about 30 years. It has generated scientific data leading to countless papers and also gorgeous images that have transfixed the science-interested public. In that sense, an inoperable Hubble would be a devastating loss," he wrote in an opinion piece for CNN.
"The best-case scenario is one in which both are operating, and we must wait for those clever engineers to work their magic to see if that is possible," he added.