Fomalhaut (alpha [α] PsA), the principal star of Piscis Austrinus, the ‘Southern Fish’, and the eighteenth-brightest star in the heavens, is the most southerly first-magnitude star visible right across the UK. It takes its name from the Arabic phrase meaning ‘the mouth of the southern fish’. It’s always great fun to try to observe these horizon-hugging southern stars.
How to observe:
Fomalhaut has a declination of –29.5°, which means when it culminates (crosses the southern meridian) it achieves at best a tree-scraping elevation of just nine and 5.5 degrees from London and Edinburgh, respectively. Ion early October, culmination occurs at about 11.15pm BST.
If you can secure an observing location with an uninterrupted southern horizon then Fomalhaut should be easy to spot, shining at magnitude +1.16. Piscis Austrinus lies almost 45 degrees below Markab (alpha [a] Pegasi), the star marking the south-western corner of the Great Square of Pegasus. Follow an imaginary line down through western Pisces and Aquarius to land on Fomalhaut. A pair of binoculars may come in handy in case of thin cloud or excessive haze close to the southern horizon.
GRAPHIC] Fomalhaut finder.jpg
DESIGN] Please show a wide-field finder with the Square of Pegasus included per text in my penultimate paragraph.
CAPTION] Fomalhaut is the principal star of the southern constellation of Piscis Austrinus, the ‘Southern Fish’. Find a flat observing horizon and look there south of Markab in