How exactly do new stars and planets form, from the clouds of gas and dust in the space between the stars? There is still so much we don’t know, about the ‘childhood’ of stars and planets. How can we obtain this missing knowledge?
Clouds of gas and dust in space slowly contract under the influence of their gravity. The more dust and gas clump together, the busier it gets in the centre of the cloud. Until the pressure is so high that hydrogen atoms start fusing with each other to form helium atoms. That is the process by which a new star ‘turns on’ and starts emitting light. Meanwhile, the dust around the baby star changes from a convex cloud to a flattened rotating dust disk. Not smooth and even, but with irregularities. Those irregularities become clumps of gas and dust that grow into planets like a snowball.
What happens to baby stars and baby planets?
When we look at our own solar system or other mature planetary systems, we only see the end result. But prior to that, how did a diffuse cloud of atoms turn into a dense star-forming cloud of molecules? How does star formation affect the dust cloud around the young star? As planets form, they sweep their orbits in the process. How quickly does a young planetary system become dust-free? How different is a second-generation star, formed from the remnants of stars from a first generation?
What else can we discover with infrared telescopes in space clouds?
SRON astronomers are trying to find ever clearer answers to these questions, by looking into space clouds with infrared telescopes. Visible light does not penetrate these clouds, so the nurseries of stars remain shrouded in mist. Infrared radiation does, however, effortlessly radiate through the dust. For example, infrared telescopes allow us to see dust discs in which baby planets have already clearly swept their orbits, but where the dust still swarms between them.
