Danish Space Research Institute to build the mirrors of ESA's Planck telescope
05 June 2000The Danish Space Research Institute (DSRI) will develop the main elements of the telescope of ESA's Planck satellite, according to a document signed yesterday by ESA and the DSRI at ESA headquarters in Paris. Planck, due to be launched in 2007, will study the origin and evolution of the Universe by observing the Cosmic Microwave Background radiation, the first light that filled the Universe after the Big Bang.
The Planck telescope system is one of the three basic payload components of the mission. Its main elements, to be developed by the DSRI, are both the primary and secondary mirrors.
The primary mirror is the 'light collector' of the payload -where the light from the astronomical sources first enters the system- it directs the light to the secondary mirror, which finally focuses the beam onto the Planck detectors.
The primary mirror will be 1.5 metres in beam diameter. Both mirrors will be made of carbon fibre, a material able to withstand the extreme conditions of the launch and outer space. Minor changes in the shape of the mirrors, or in the degree of smoothness of their surface, could spoil the measurements.
The Planck telescope is of the so-called off-axis type, which means that the secondary mirror is beside the primary mirror instead of facing it. Thanks to this design the beam of light enters the telescope without any disturbance, a key requirement to preserve Planck's sensitivity.
DSRI has been involved in the design of the Planck telescope since its earliest phases, begun several years ago. DSRI represents a consortium of Danish scientific institutions, namely DSRI itself, the Theoretical Astrophysics Centre Copenhagen and the Niels Bohr Institute for Astronomy, Physics and Geophysics.
The document signed yesterday is the "Arrangement between the European Space Agency and the Danish Space Research Institute on the management, execution and funding of the main elements for the telescope for the Planck Project".
Footnote about Planck
The Planck satellite, one of ESA's main missions for this decade, has been designed to help answer key questions for humankind: how the Universe came to be and how it will evolve. To fulfil its mission Planck will examine with unprecedented sensitivity and angular resolution, the small anisotropies of the first light that filled the Universe after the Big Bang, the so-called Cosmic Microwave Background radiation. It will carry two arrays of highly sensitive detectors that are now being built by more than 40 institutes, most of them European and some from the United States. Planck will be launched in 2007 together with ESA's far-infrared space telescope, FIRST. They will separate shortly after launch and will be operated independently from different orbits around the second Lagrangian Point located about 1.5 million kilometres away from Earth.
Jan Tauber, Planck project scientist