ACR-News

A CRYOGENIC refrigeration system may help mankind learn more about the creation of the universe.
The Herschel space telescope launched last week with its companion spacecraft Planck will measure radiation from the 'Big Bang', providing scientists with information about planet and star formation.

The Herschel telescope, which has a diameter of 11.5ft, is said to be the biggest telescope ever sent into space. The primary detectors on both telescopes have to be kept as cold as possible to be able to obtain high-resolution data while they make their observations.

Herschel carries what is basically a vacuum flask or cryostat, filled with more than 2,000 litres of liquid helium supercooled to 1.65K, ie just 1.65°C above absolute zero.

Two of the instruments also have built-in coolers to bring the operating temperatures of the detectors down to -272.7ºC, just a third of a degree above absolute zero.

The Planck spacecraft incorporates a passive cooling system using radiative shields facing deep space to achieve temperatures down to about 60K before active cryogenic cooling systems bring the detector temperatures down as low as tenth of a degree above absolute zero.

The Herschel telescope and Planck will take several weeks to reach their separate orbits, nearly a million miles from Earth.