Ponder the Pleiades

This piece was originally broadcast on Radio Scilly in February 2019
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Have you ever looked up at the stars on a clear Winter night and noticed a faint but bright fuzzy patch, somewhere near Orion? Unmistakeably a glowing thing, but not the pinpoint of light like a regular star. You might have rubbed your eyes or wondered…what IS that cloudy starry thing?

Well that would be the Pleiades – also known as the Seven Sisters. Officially part of the constellation Taurus. The Pleiades are one of the nearest star clusters to us here on planet Earth. A star cluster being simply a group of stars, bound together by gravity. The Pleiades are an open cluster – which means they’re all relatively young stars. These types of clusters are only found in spiral galaxies, like ours, the Milky Way.

To find the Pleiades, follow the line of Orion’s belt up, through red-looking star Aldebaran (the main star in Taurus, and easy to spot as it’s a bright one). Keep going in pretty much a straight line and you’ll reach your cluster destination. This is much easier to master with the naked eye. Once you’ve found it, then grab your binoculars and point them in the area you were just looking!

The Pleiades are a fuzzy mystery with the naked eye but through binoculars are a real treat – you can clearly make out the 7 brightest stars, and many, many more. Grab any pair you can find and give it a go – you won’t be disappointed. You might need to scout around a bit to locate the cluster but once you’ve found it, it’s unmistakeable.

With the naked eye, if you want to make sure you’ve found it, just direct your eyes’ focus ever so slightly to one side of the fuzzy patch. Funnily enough it will look clearer – that’s because the edge  of our vision is more sensitive to subtle light, because the majority of our light-sensing rod cells are located in the peripheral retina. The opposite is true for colour though, so don’t be attempt this technique when trying to be sure that you’re looking at red planet Mars! Enough of the eye science.

Back to the Pleiades. In mythology, the Pleiades are the seven divine sisters – supposedly very attractive ones at that – daughters of the titan Atlas and the sea-nymph Pleione, hence Pleiades. However it’s thought that the name of the cluster actually comes from the Ancient Greek plein, meaning to sail, as the appearance of the star group in the sky marked the beginning of the Greek sailing and navigation season. Interesting fact for those – like us on Scilly – reliant on boating!
Here and now, the Pleiades dropping lower in our sky is more likely to indicate the start of our tourist season. Winter having been fairly rubbish all round for stargazing, we’re hoping to spend more time up at the Observatory as Spring comes along. Anyway, grab a look at the wondrous Pleiades while you can – stay hopeful for a patch of clear sky!

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