Herschel, an infrared space observatory, was launched on an Ariane 5 space rocket from French Guyana on May 14, 2009. After a few short weeks it reached its nominal orbit 1.5 million km away from the Earth, facing away from both Earth and Sun. From this vantage point Herschel will direct its giant telescope not only towards our own galaxy, the Milky
Way, but also at very young galaxies in the far reaches
of the universe.
Since Herschel’s useful life is limited to four years,
infrared astronomers will be exceedingly busy during this
time. The brief lifetime is due to the fact that Herschel consumes its liquid Helium to keep its science instruments cold.
After the coolant runs out, Herschel's three instruments,
which only function close to absolute zero temperatures
(-273°C), will become useless.
During its
short but intense life Herschel will allow astronomers
to see far-infrared and sub-millimeter light from stars,
galaxies, and other matter in space, such as cold and
dark material between stars. The primary focus of Herschel's
mission will be to determine how stars and galaxies are
born. Star formation occurs in our own galaxy (the Milky
Way), and Herschel will closely examine regions where
dust and gas is in the process of turning into a new star.
Herschel will also look beyond our Milky Way Galaxy, much
deeper into space and time, studying remote (very old)
galaxies of our universe, providing information infrared
astronomers require to determine how galaxies are born.
