Coolest Spacecraft Ever In Orbit (-273 Degrees Celsius)
Friday, July 3, 2009 - 23:35
in Astronomy & Space
On July 2 the detectors of Planck's High Frequency Instrument reached their amazingly low operational temperature of -273°C, making them the coldest known objects in space. The spacecraft has also just entered its final orbit around the second Lagrange point of the Sun-Earth system, L2.