Artist's impression of Planck
Credit: ESA/AOES Medialab

Planck was an ESA space telescope, active from 2009 to 2013, designed to map the small fluctuations in the cosmic microwave background radiation (CMB). Planck greatly improved upon the observations of WMAP, a NASA probe which operated from 2001 to 2010. As of 2013, Planck has provided the most accurate estimates of several important measurements, such as the densities of normal matter and of dark matter in the Universe.

Some facts about the telescope:

  • Mass: 1,950 kg
  • Mirror dimensions: 1.9 x 1.5 metres
  • Launch date: 14th May 2009

On 21st March 2013, Planck's first all-sky map of the cosmic microwave background was released (pictured below). The spacecraft carried two instruments, one which detected higher frequencies than the other. The telescope operated in the microwave and infra-red regions of the electromagnetic spectrum.

Alongside mapping the CMB, the scientific goals of Planck included:

At the end of its mission, Planck was moved into an orbit around the Sun. This prevents the spacecraft from colliding with or endangering any future missions. 

Map of fluctuations in the cosmic microwave background taken by Planck
Map of the fluctuations in the cosmic microwave background radiation
Credit: ESA/Planck