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EVERY star you can see in the sky with the naked eye belongs to our galaxy, the Milky Way. Most of these, including our sun, are part of a spiral arm that stretches out from the heart of the galaxy.

But the Milky Way鈥檚 dense centre is packed with stars and other spiral arms that sit in a flat disc in space. From our position, the view towards the middle of this disc looks like a band arching across the sky.

Astronomers aren鈥檛 sure precisely how many stars are contained in our galaxy, but estimates put it at between 100 billion and 400 billion. The central core is one of the densest parts of the galaxy, which means that a lot of these billions of stars lie there.

They are held in place by the huge force of gravity created by a supermassive black hole at the heart of the Milky Way called Sagittarius A*, which is about 4 million times the mass of the sun. Most spiral and elliptical galaxies have a black hole like this at the centre.

Sagittarius A* sits some 26,000 light years from the sun. We can鈥檛 see the black hole directly, but it is possible to see the bright cluster of stars that lie around it, making up what is called the galaxy鈥檚 central bulge.

Some part of the disc of the Milky Way is visible all year round, and the area you can see will vary depending on when and where you are looking. The best time to see it is from March to September. The rest of the year, Earth is on the wrong side of the sun for you to get a perfect view of the centre of the galaxy.

To see the Milky Way鈥檚 centre, you need dark skies and a clear night. Pick a time when there is little or no moonlight to reduce the glare from our natural satellite and try to go as far away from city lights as you can.

The new moons on 10 July or 8 August would be perfect. Give your eyes time to adjust to the darkness, which should take around 40 minutes.

Make sure that the night is as dark as it can be. This is particularly important in the northern hemisphere if you are trying to see it in the summer months and might mean staying up until the early hours. In the southern hemisphere in July, your best view is at around midnight.

If the conditions are right, you should have no trouble finding the band of the Milky Way. It will appear as a large, hazy streak across the sky.

The black hole at the core of the galaxy is in the Sagittarius constellation, on the border with the constellation Scorpius. In dark skies, you can clearly see the central bulge and a brighter collection of stars in the region.

In the northern hemisphere, this will be visible when looking south. The best views of the central bulge will be from the southern hemisphere, where it will be high in the sky.

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