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SOME constellations force you to look at them. Their brightest stars are so clear, even in a night sky full of light pollution, that they draw you in. Others sit there quietly, waiting for you to find them.

This week, we are looking for one of the latter. Cancer is a humble constellation, nestled in between its louder neighbours Gemini and Leo. Without any particularly bright stars of its own, Cancer is the faintest of all the zodiacal constellations, which makes it tricky to find. But once you have spotted it, there will be something beautiful waiting for you: the Beehive cluster (pictured right).

Cancer is visible from all over the world, and April is a great time to see it. Start by locating three bright stars: Regulus in Leo and the twins Castor and Pollux in Gemini. To find Castor and Pollux, first find the three stars in Orion’s belt. From there, look for the blueish white Rigel in Orion’s right foot and the red giant in Orion’s left shoulder, called Betelgeuse. Draw a line from Rigel through Betelgeuse and continue that line until you see two bright stars. These are Castor and Pollux.

Next you need to find Regulus, the brightest star in Leo. You can do this using Procyon, which is the brightest star in Canis Minor

If you are in the northern hemisphere, then Gemini will be sitting above Orion, and Procyon will be to the left of the two of them. If you are in the southern hemisphere, Gemini will appear below Orion, and Procyon will be to the right. Either way, draw a line from Rigel to Procyon, then continue this until, if you are in the northern hemisphere, you see a bright star nestled at the bottom of what looks like a question mark. In the southern hemisphere, it will be an upside down question mark. This bright star is Regulus.

Now you have found Leo and Gemini, look directly between the two. The faint, upside-down Y, as seen in the northern hemisphere, is Cancer; in the southern hemisphere, it looks like a normal Y. In a brightly lit area, you won’t see much in this patch of the sky, but if you have dark skies and little moonlight, you will be able to make out the Beehive cluster.

Sitting at the centre of Cancer, this is one of the brightest open star clusters – a group of young stars that all formed from the same cloud of gas and dust – in the night sky, containing about 1000 stars. Like the Pleiades and the V-shaped Hyades in Taurus, the Beehive cluster is about 600 million years old, and astronomers think it is possible all three formed from the same cloud of dust.

With the naked eye, the Beehive cluster looks like a fuzzy blob about 1.5 times the size of the full moon. But use binoculars or a telescope and you will see lots of beautiful stars. In fact, this cluster was one of the first bits of the night sky Galileo observed with his telescope, in 1609.

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