The first scientific results from the European Space Agency’s (ESA) Herschel infrared space observatory are revealing previously hidden details of star formation.
New images show thousands of distant galaxies furiously building stars and beautiful star-forming clouds draped across the Milky Way. One picture even catches an ‘impossible’ star in the act of formation.
Herschel is the largest astronomical telescope ever to be placed into space. The diameter of its main mirror is four times larger than any previous infrared space telescope and one and a half times larger than Hubble.
As stars begin to form, the surrounding dust and gas is warmed up to a few tens of degrees above absolute zero and starts to emit at far-infrared wavelengths. The Earth’s atmosphere completely blocks the majority of these wavelengths and thus observations from space are necessary.
Using its unprecedented resolution and sensitivity, Herschel is conducting a census of star-forming regions in our Galaxy.
“Before Herschel, it was not clear how the material in the Milky Way came together in high enough densities and at sufficiently low temperatures to form stars,” says Sergio Molinari, Istituto di Fisica dello Spazio Interplanetario, Roma.
Herschel is also a prime instrument for detecting one of the smallest forms of matter: molecules. It has made the first discovery in space of a new ‘phase’ of water. It is electrically charged and unlike the more familiar phases, namely solid ice, liquid water and gaseous steam, it does not occur naturally on Earth.
In the birth clouds surrounding young stars, however, where ultraviolet light is pumping through the gas, this irradiation can knock an electron out of the water molecule, leaving it with an electrical change.
“These are still early days for Herschel and this is just the beginning of all the science that we will get from this mission in the years to come,” says Goran Pilbratt, ESA Herschel Project Scientist.