Planck’s first light

Planck first light

Credits: ESA, LFI & HFI Consortia. Background optical image: Axel Mellinger. ESA’s Herschel space telescope sent its first view back some months ago. Its companion microwave observatory, Planck, which was launched at the same time, has now achieved first light [BBC report]. From the ESA press release.

The ‘first light’ survey, which began on 13 August, was a two-week period during which Planck surveyed the sky continuously. It was carried out to verify the stability of the instruments and the ability to calibrate them over long periods to the exquisite accuracy needed. This survey was completed on 27 August, yielding maps of a strip of the sky, one for each of Planck’s nine frequencies. Each map is a ring, about 15° wide, stretching across the full sky. Preliminary analysis indicates that the quality of the data is excellent.

ESA’s video introduction to Planck. Credit ESA TV 2009.