Astro FOTD: Taking Out the Trash

Stars seem to be born in clusters of several hundred or more stars, out of clouds of cool dust and gas with 1000 or so solar masses. This process usually leaves a lot of left over dust and gas, as in the Pleiades cluster:


The Pleiades were born 100 million years or so ago, with the largest stars having recently become blue giants. Notice all the dust reflecting their light.  This is good evidence that the cluster did not produce any stars that have become supernovae - yet anyway.  If it had, they would have swept all that dust (and gas) out.  The largest, brightest stars are about 5 solar masses, probably too small to go super, unless they are part of a binary and go the Type Ia route.

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