You've probably heard there's a supermassive black hole at the center of the Milky Way - and also that near the center of our galaxy there are a lot more stars. But did you ever think hard about what the Galactic Center is like?

I haven't, until recently. As a kid I read about it in science fiction - like Asimov's Foundation trilogy, where the capital of the Empire is near the Galactic Center on the world of Trantor, with a population of 40 billion. That shaped my impressions.

But now we know a lot more. At the center there's a black hole of about 4 million solar masses - a whole story on its own. But within 4 light years of the center there are over 10 million stars! Remember, the nearest stars to our Sun are that far away.

Even weirder, among these stars there are lots of old red giants - but also many big, young stars that formed in a single event a few million years ago. These include about 100 'OB stars', which are blue-hot, and 'Wolf-Rayet stars', which have blown off their outer atmosphere and are shining mainly in the ultraviolet.

Nobody knows how many stars were able to form despite the gravitational disruption of central black hole: this is called the 'paradox of youth'.

Stars don't seem to be forming now at the Galactic Center. But there's a big ring of thick gas - molecules rather than atoms - orbiting the center at a distance of 6 light years. This is called the Circumnuclear Disk, and some predict that it will cause a 'starburst' in 200 million years, with many stars forming rapidly, and supernovae going off at a hundred times the current rate! As gas from these falls into the central black hole, life may get very exciting.

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