KOURU, FRENCH GUIANA - The Ariane 5 rocket is to launch today, carrying two telescopes which are expected to reveal important information about star birth and galaxy formation. They may also even help answer questions such as how the universe began.
The Herschel and Planck observatories are the last missions to be launched under ESA’s Horizon 2000 long-term plan for space science, which started in 1985. They will separate soon after lift-off and head to L2, the second Lagrange point - a point in space where an object appears to be stationary with regard to two larger objects, such as the Earth and the Moon - where they will operate from independent orbits.
L2 is a local gravitational point that is fixed in the Earth-Sun system and is situated on Earth’s night-side. This location allows Herschel and Planck to shield their sensitive instruments from solar radiation.
Herschel contains the biggest ever mirror to be put into space - 3.5 meters across. It will observe the cool regions of the universe through long-range infra-red - a first for an astronomy mission. It will also study comets and asteroids, and investigate how planets are formed.
Meanwhile, Planck will examine light from just 400,000 years after the Big Bang through microwave wavelengths, with more sensitivity and accuracy than has previously been possible. Scientists are also hoping that it will be possible to use it to calculate the total number of atoms in the universe, and thus establish the total mass of dark matter.
The National Aeronautics and Space Administration's Herschel Science Center at the California Institute of Technology will work with US and European Planck scientists to analyze the satellites' data.
The launch can be watched live, here.