The fourth spacewalk to upgrade the Hubble: replacing an electrical panel and a little drama

As of the writing of this news, the fourth spacewalk is in the final stages * Astronaut Mike Massimino feared a leak in his space suit, the air pressure was checked and found to be normal

Astronauts on mission STS-125, Mike Massimino and Mike Good performed the fourth and penultimate spacewalk tonight to upgrade the Hubble Space Telescope. They continued with repairs and improvements that would extend the life of the telescope into the next decade.

The spacewalk began at 09:45 EST (16:45 Israel time) and lasted about six and a half hours.
The main task was work on the Space Telescope Imaging Spectrograph (STIS). Massimino and Goode replaced a low-voltage power supply board containing an electrical converter that had failed. Due to these problems with the power supply, the STIS device has been operating in a safe mode since August 2004. In a test conducted on the device from the control room on the ground, it testified that it is alive and that it is receiving the electricity it needs.

A little drama ensued when Massimino noticed a drop of white liquid on his glove. He feared that this was a hole through which the air exits the space suit. He photographed the suspicious drop, and at the same time the control room personnel checked the air pressure in his suit which was normal and did not require him to run quickly to the Atlantis airlock.

The spacewalkers also installed on the Hubble one of the two isolation sheets they brought with them on the Atlantis shuttle. The insulating material was installed on the bay 8 door of the telescope.

correction

A few days ago it was reported that the astronauts were unable to install the Wide Field Camera/Planetary Camera #3 which is supposed to be the Hubble's main workhorse like its predecessor which was removed this week after 16 years of successful operation. It turns out that despite the unruly screw, the camera is attached to its place and it works well, at least its devices, as can be seen from the test sessions conducted by NASA personnel from the ground. The news was updated at the time of writing, but for some reason no mention of this update was found before.