Wednesday, 4 June 2008

Twinkle twinkle little Star

Back when people used to look up at the sky and wonder what all those lights in the sky were, back when so little was known about the processes by which the cosmos is lit, and by which almost everything we are was created... back then eh!

Nowadays we know that those lights in the sky are in fact massive balls of gas, converting hydrogen into helium at their cores though a process of nuclear fusion. Of course this is just a simplistic description of your standard main sequence star, there are many many other stages of stellar evolution, and indeed types of star.

The point is that we now know this. Through a multitude of methods we can determine the composition, size and distance of those stars that we see. They are no longer unfathomable objects in the sky.

That said, nothing beats a close up look. Most of the time stars other than our Sun are mere points of light. However, one of the better known beasties, Betelgeuse, is both large enough (absolutely freakin' huge) and close enough for surface features to be resolved.

So having read through all that, i'd like to direct you to this short article from the Cavendish Astrophysics website where you can read up on the imaging methods used to obtain the pictures of the stellar disk in question. The images don't show much detail - but you have to remember that this object is 430 lightyears away. Thats 27 million times the distance from the Earth to the Sun, so you can forgive it for not looking quite as impressive!