HST’s ACS Camera Back In Service

By Michael on October 8, 2006 at 11:30 am | In Blog Posts | No Comments

In a little reported story, the Advanced Camera for Surveys (ACS) onboard the Hubble Space Telescope (HST) went offline on Sept. 23, 2006.

After an initial analysis, the Board determined that the ACS anomaly is confined to only one of the three channels – the High Resolution Channel (HRC), which performs about 18% of ACS science.

The unaffected channels are the Wide Field Channel (WFC), that provides nearly 72% of all ACS observations, and the Solar Blind Channel (SBC), which is used only about 10% of the time.

Hubble engineers were able to successfully bring the Wide Field Channel back on line September 30, and resumed normal WFC science observations on October 1. Among its many major scientific accomplishments, the WFC enabled the famous Hubble Ultra Deep Field (HUDF) discovery – a stunning view of more than 10,000 galaxies that assisted astronomers in determining how galaxies originally formed in the early universe.

Engineers are examining strategies for potentially returning the HRC to service. They report that all other subsystems on the telescope are functioning nominally.

So some of the ACS was brought back online on Oct. 1, 2006.

As you may or may not know, HST’s spectrograph, the Space Telescope Imaging Spectrograph or STIS, is offline permanently, which is a huge blow to astronomy. STIS was the only high-resolution spectrograph capable of ultra-violet observations, something you can’t do from the ground.

I agree with the many astronomers who believe that HST is too valuable to let decay. We should proceed with the scheduled servicing mission as soon as possible.