Skylog: Looking Up!

Herschel Space Observatory sees cool cocoons where stars form

The Herschel Space Observatory is a  space observatory that was carried into orbit in May 2009. Herschel is a European Space Agency mission with significant participation from NASA. It is the fourth 'cornerstone' mission in the ESA science program.
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.

This image is taken looking towards a region of the Galaxy in the Eagle constellation, closer to the Galactic centre than our Sun. Here, we see the outstanding end-products of the stellar assembly line. At the centre and the left of the image, the two massive star-forming regions G29.9 and W43 are clearly visible. These mini-starbursts are forming, as we speak, hundreds and hundreds of stars of all sizes: from those similar to our Sun, to monsters several tens of times heavier than our Sun. These newborn large stars are catastrophically disrupting their original gas embryos by kicking away their surroundings and excavating giant cavities in the Galaxy. This is clearly visible in the 'fluffy chimney' below W43.


This image, in the constellation of Vulpecula, shows an entire assembly line of newborn stars. The diffuse glow reveals the widespread cold reservoir of raw material that our Galaxy has in stock for building stars. Large-scale turbulence from the giant colliding Galactic flows causes this material to condense into the web of filaments that we see all over the image. These are the ‘pregnant’ entities where the material becomes colder and denser. At this point, gravitational forces take over and fragment these filaments into chains of stellar embryos that can finally collapse to form baby stars.

For more information about the Herschel Space Observatory click here and here

Sources for this article: ESA Portal, SpaceRef, NASA-Herschel, wikipedia.org