PACS switch-on and initial functional tests
PACS has successfully been switched-on and passed the first activity in orbit, the so-called Short Functional Tests, on 24 May 2009. Results confirm that all mechanisms are moving on a very similar way than during the last ground test in Kourou, calibration sources are heated up, the sorption cooler is electrically functional. During a period of one hour the spectrometer's photoconductor arrays were fully operated, signal in the blue array is nominal, for the red array the spacecraft temperature conditions were still a bit high. Functional tests of the photometer's bolometer detectors have proven that we have no new "dead" pixels in any of the arrays.
In the coming days the bolometer's sorption cooler will be recycled before the acquisition of its first real optical signal and both spectrometer and photometer array settings will be fine tuned for in-orbit environment.
The PACS PI Albrecht Poglitsch reports "under the given boundary conditions of this phase of the mission and the scope of this test, our general impression is that things went as well as they possibly could have. Let's hope it will continue like this!"
[R.Vavrek from MOC ESOC, posted 25 May 2009]