Our home galaxy. It's a spiral galaxy, approximately 100 000 light years across. To get a better understanding of this number: if you want to travel from one end of the galaxy to the other at the speed of a modern jet plane (1000 km/h) you'd need about 108 billion years, or almost 8 times the universe's current age of 13.8 billion years! The Milky Way contains between 200 and 400 billion stars and, as you know, our Sun is just one of them. And there are at least as many planets, probably many more. Probability calculations show that there are likely to be tens of billions of Earth-sized planets in the habitable zones of other stars just in our Milky Way, which means that their temperature is just right for there to be liquid water on their surface. That's mind-blowing!

In the centre of the Milky Way there is a massive black hole; or more precisely: a supermassive black hole. It has a mass of several million times that of our Sun, but with its distance of 27000 light years from our Solar System the required safety distance is more than respected. Every star and all the gas orbit around the centre of the Milky Way. The Sun's orbital speed is 220 km/s and it takes our home star about 240 million years to complete one full orbit.

The Milky Way is part of the Local Group of galaxies, which itself lies on the outskirts of the Virgo Supercluster, our home supercluster in the universe.

If you want to know how the Milky Way might look from far away you have two options: have a look at our artist's impression images of the Milky Way or check our image of the galaxy NGC 6744 which is considered to closely resemble our own galaxy.


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Published by Published or last modified on 2014-03-05