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ASTRONOMY

If Polaris is the North Star, is there a ‘south star’?

In the Northern Hemisphere, astronomers are very fortunate to have a star, Polaris, very close to the north celestial pole. Polaris will appear to stay fixed in position while the constellations seem to rotate around it due to the Earth’s spin about its axis. It is a sensible assumption that there might be a similar guide at the south celestial pole (SCP), the point of sky around which the Southern Hemisphere stars appear to rotate.

However, Polaris is above the celestial pole purely by chance, and there is no useful beacon marking the SCP outright. The closest star, Sigma Octantis in the constellation Octans, is a very dim, fifth-magnitude star which is extremely hard to make out with the naked eye. While Sigma Octantis is the ‘south star’ to our ‘North Star’, it does not have the same usefulness as Polaris for astronomers, so often falls by