Herschel sees super-massive stars forming
Mon, 10th May 2010
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from the show Does Beer Kill Brain Cells?
The recently-launched Herschel space telescope has revealed a new way in which massive stars might form.
Stars are the major building block of the Universe, and our star - the Sun - powers almost all the life on Earth, so understanding the workings of the Sun and other stars like it is very important.
One big problem is that, according to present theories, stars shouldn't get bigger than 8 times the mass of the Sun. This is because the light they produce should blow away the surrounding material before it can become part of the star. Nevertheless, there are many stars of this size in the galaxy, so space scientists know that there must be a piece of the puzzle missing. But investigating this sort of problem has been difficult until now because young stars are surrounded by clouds of opaque dust and gas, which obscure our ability to see what's going on.
However, in May 2009, the European space telescope Herschel was launched. It is the largest space telescope ever deployed and is equipped with a 3.5m mirror and is set up to study the the Infra Red region of the spectrum. This means that it can see straight through the dust that has hampered earlier attempts to witness the births of new stars and it can also see objects that are relatively cool, which means that it can peer into the deepest recesses of space where new stars are forming.
Recently, Herschel spotted a "bubble" of hot gas that is expanding supersonically through a cloud of gas and dust, producing a high density shock wave at the surface. Intriguingly, on this surface, a star is beginning to form and already has a mass of between eight and ten times that of the Sun and is still growing. Shock waves like this might therefore be the way that these stars form.
Herschel has also been sending back beautiful pictures of stars forming in stellar nurseries and galaxies forming stars in the early universe. There should me much more to come.