How much carbon monoxide is there in space?

This is one of the questions that ESA’s Planck mission tries to answer. At an international conference in Bologna (Italy), attended by astronomers from all over the world, its leaders have unveiled thefirst carbon monoxide distribution mapthat covers the whole sky. Carbon monoxide is an ingredient in cold clouds in the Milky Way and other galaxies. It is in these clouds, mainly made up of hydrogen molecules,where the stars are born.

However, hydrogen molecules are difficult to detect because they hardly emit radiation. Carbon monoxide forms under similar conditions and, although it is much rarer, it emits light more easily and is therefore better detected. Astronomers use it as an indicator of the presence of hydrogen clouds. “Planck turns out to be an excellent all-sky carbon monoxide detector,” says Jonathan Aumont of the Institut d? Astrophysique Spatiale, Universite Paris XI, in Orsay, France.

Observations of carbon monoxide carried out with radio telescopes on the ground require a long observation time, and therefore are limited to the regions of the sky where molecular clouds are known to exist – or are expected to exist. The great advantage of Planck is that it scans the entire sky, and allows you to detect concentrations of molecular gas anywhere.

Planck has also detected a mysteriousmicrowave hazewhich for now constitutes a mystery. It comes from the region around the galactic center, and appears to be synchrotron-type radiation. This radiation is produced when electrons pass through magnetic fields after being accelerated in supernova explosions.