Planck

Mapped the CMBcosmic microwave backgroundThermal radiation released 380,000 years after the Big Bang, now at 2.7255 K and peaking near 160 GHz. Its temperature and polarisation anisotropies, at the 10⁻⁵ level, constrain the content and geometry of the Universe. over the whole sky in nine bands from 30 to 857 GHz, with HEMT radiometers in the Low Frequency Instrument and bolometersbolometerA detector that measures incoming power through the heating of an absorber. Transition-edge sensors, held at the edge of a superconducting transition, are the standard for CMB and submillimetre cameras. cooled to 0.1 K in the High Frequency Instrument. Its temperature and polarisationpolarimetryMeasuring the polarisation of incoming radiation. It encodes magnetic-field geometry, scattering and emission mechanisms; in the CMB it separates E- and B-mode patterns. power spectra fix the six ΛCDMΛCDMThe standard cosmological model: a flat universe with dark energy as a cosmological constant (Λ), cold dark matter and ordinary matter, fit by six parameters. parameters to around a percent, and its maps define the Galactic dust and synchrotron foregroundsforegroundsEmission between us and the signal of interest; for the CMB, Galactic synchrotron, free–free and dust. Component separation uses their different spectra across many frequencies to remove them..

Operator

ESA

Orbit

Sun–Earth L2

Aperture

1.9 × 1.5 m primary mirror

Passband

30 GHz – 857 GHz

Launch

14 May 2009

End

23 October 2013