Fomalhaut; the loneliest star?

17th October 2017

For the stargazing among us Autumn can be a particularly grim time of year. That chill of the night only gets worse the closer we edge toward Christmas and the casual stargazer could be forgiven for not wanting to be outside too much for extended periods of time.

Winter is coming

If you’re looking for a quick astronomy fix, Fomalhaut in the constellation of Pisces is the most easily visible in the northern hemisphere throughout the autumn months. One of the brighter stars in the sky, it is only outshone by Pollux and our own sun. With no apparent neighbours, it stands out even when there’s a lot of moonlight.

To spot Fomalhaut, look to the south. If you know Pisces, you’ll recognise it as the brightest star in the constellation group.

Where to spot Fomalhaut

Fomalhaut was once thought to be a solitary being, given the absence of easily spotted neighbours. If there ever was a cause to adopt a star surely it would be Fomalhaut. Yet, on closer inspection, scientists have determined that it has quite a bit of company, being surrounded by an asteroid belt and being accompanied by fellow stars within its gravity well.

In the star map, two dimmer stars  are labelled; Fomalhaut B and Fomalhaut C.  All three of the Fomalhauts closely interact with each other when moving through the cosmos together and are designated as a triple star system.

Eye of Sauron

Their relative closeness to Earth means the three stars combined cover a wide berth in the autumn sky, a whole 8°.

The above image is from Hubble telescope and has been nicknamed the Eye of Sauron, due to the way the asteroids’ orbit appear under false colouring. The white dot in the centre of the image highlights Fomalhaut’s location, while the small white box at lower right pinpoints Fomalhaut b’s location.

The lonely star of Pisces may not turn out to be so lonely after all. And if you’re looking at naming a star close by to Fomalhaut on the intergalactic star database check out the Pisces section of the Star Registry website.

Though if it’s not a Pisces star you’re looking to get, you can get another star named after you as part of a binary star system, similar to Fomalhaut.