SPIRE – the coldest place in space!

In-flight testing of SPIRE has continued during the last three days, with members of the SPIRE team at  the European Space Agency’s control centre in Darmstadt, Germany, commanding the instrument in real time and monitoring the data being transmitted back to Earth.

On Wednesday May 21, they checked out the delicate moving mechanism used in the SPIRE spectrometer, and found it to be in perfect condition.

On Friday, May 22, they operated SPIRE’s internal refrigerator for the first time and it also worked perfectly, cooling the detectors down to only 0.29 degrees above absolute zero. Other SPIRE team members at the Rutherford Laboratory in Oxfordshire were able to see the data live on their screens and follow the events.

SPIRE now holds the record for the coldest known place in space.  In a few weeks, a similar cooler in the Herschel-PACS instrument will be operated – it will be interesting to see if PACS can beat SPIRE’s record.  The competition will be fun, but soon we will both be out-done by the Planck-HFI cooler, which is designed to get to 0.1 K.