Planck will be the third spacecraft to investigate the CMB, after Nasa's COBE and WMAP satellites.

BBC: Telescopes ready for rocket ride

WMAP's data are in close agreement with this model, but that agreement is not perfect.

ECONOMIST: The shape of the universe

WMAP's picture is detailed enough to discern the relevant blips (assuming they are there) is not yet clear.

ECONOMIST: Planck-scale physics

The first was COBE, launched in 1989, followed by WMAP, launched in 2001.

CNN: Better 'baby picture' of universe emerges

Currently, only one spacecraft inhabits L2: the US space agency's WMAP probe (which is making observations on which Planck hopes to build).

BBC: World's most daunting parking job

Data from the WMAP probe was seen as a major confirmation of this last point when it was first made public in 2003.

FORBES: While Physicists Celebrate Higgs, Cosmologists Fret About The Big Bang Model

In July, astronomers from the Sloan Digital Sky Survey (SDSS), which aims to map out a million galaxies, published a research paper in which they superimposed their own galaxy-clustering data on Wmap's microwave data.

BBC: NEWS | Science/Nature | Dark energy tops science class

Details of these predicted variations have been confirmed by the Wilkinson Microwave Anisotropy Probe (WMAP) and other experiments, and will be further tested by the Planck satellite, data from which is currently under analysis.

BBC: The observable Universe and beyond

Steinhardt and Turok believe that there may even be direct observational evidence of events that occurred prior to the Bang, but the instruments to capture this will depend on satellites far more subtle than WMAP.

FORBES: While Physicists Celebrate Higgs, Cosmologists Fret About The Big Bang Model

In February, the Wilkinson Microwave Anisotropy Probe (Wmap) satellite took the most detailed picture yet of the cosmic microwave background - an image of the infant cosmos when it was less than 400, 000 years old.

BBC: NEWS | Science/Nature | Dark energy tops science class