Planck, ESA's time machine, is Europe's first mission that will look at the
very edge of the observable Universe by studying the cosmic microwave
background, the relic radiation of the Big Bang.
This radiation, which permeates space in all directions, is our direct link
to the birth of the Universe. It carries a picture of the cosmos as it was
about 300 000 years after the Big Bang, or about 14 thousand million years
ago, when light started to travel freely in space.
The third and most advanced space experiment of its kind, the Planck
telescope will measure tiny variations in the temperature of the cosmic
microwave background with the highest-ever precision. These variations will
reveal the fingerprints left by the 'seeds' of the structures, such as galaxies, that we observe in our Universe today. With its sensitivity, Planck will reveal much more about the infant Universe than any mission has done so far.
Planck will help determine the properties of the Universe with great
accuracy: its geometry, the total density of normal and dark matter, the
total amount of atoms in the Universe, and the nature of dark energy.
The spacecraft carries a telescope and two powerful instruments operating at
radio to sub-millimetre wavelengths. Their detectors are kept at temperatures close to absolute zero by a sophisticated cryogenic system.
Launch: 2009, on an Ariane 5 ECA rocket from Kourou, French Guyana
Orbit: around the 2nd Lagrangian Point, or L2, located at about 1.5 million
km from Earth in the direction opposite to the Sun
Lifetime: a minimum of 15 months
Captions of inset images
Image 1
Planck balance tests
Planck mounted on the Centre of Gravity and Inertia measurement machine
during balance tests at Thales facilities in Cannes, France. The conical
structure visible below the spacecraft is the mass properties adapter, a
device that attaches it to the measurement machine.
A spin-stabilised spacecraft, Planck will rotate about its axis as it
operates. The balance tests are carried out to ensure that the spacecraft
spins smoothly around its axis.
Image 2
Preparing for Transport
The payload module of the Planck spacecraft was wrapped inside a protective
textile cover to prepare the spacecraft for transport on 21 April 2008.
This image shows engineers wrapping the upper part of the payload module,
including the telescope mirrors and baffle. The 1.75 x 1.5 m primary mirror
is visible on the left with the focal plane unit just below.
Image 3
Planck focal plane unit
A close-up of the Planck focal plane unit while being prepared for thermal
balance and thermal vacuum test
