14 DAY TRIAL // The recently refurbished Hubble Space Telescope gave engineers at NASA a startle, when it froze up just weeks after the STS-125 space shuttle Atlantis mission to repair it. During the downtime, which lasted for about 14 hours on Monday morning, the most famous observatory in the world locked its handlers from accessing its instruments, and experts believe that a glitch in the newly installed data handling unit may be responsible for this event.
“It locked up on us. It wouldn't send any telemetry and wouldn't accept any commands. It totally isolated the instruments from either onboard or on the ground,” Preston Burch, the Hubble program manager, told Space. It was only after engineers remotely rebooted the telescope that they were able to access the telemetry and the instruments aboard it. The satellite was first turned off, and then remotely restarted, from its control center at the Goddard Space Flight Center, in Greenbelt, Maryland.
According to the readings NASA engineers have seen, the instruments aboard Hubble are operating at full capacity at this time, but the glitch that happened this week has delayed the checkout process of the newly installed equipment by more than a week. The telescope got its fifth and last servicing mission last month, when astronauts aboard Atlantis performed a series of five back-to-back spacewalks, in which they replaced two instruments, installed two new ones, changed batteries and heat insulators, and also added new gyroscopes.
The observatory has two strings of data-handling units onboard, String A and String B, which can be switched in case something happens to one of them. However, Hubble has been using String B since it was first launched, and the reboot on Monday was the only option left before engineers would consider switching to the redundancy gear. The main concern about doing that is the fact that those back-up equipments are already more than 19 years old, and there's no telling how they might react if they are brought suddenly online, Space informs.