October 2018
WorldMags.net October at a glance October’s a great time to explore the aquatic constellations
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he early evening sky is dominated by Pegasus, with the Great Square of Pegasus creating a large void among the stars. To the south and southeast of the Great Square is an ill-defined region of sky known informally as The Sea. It gets this name because it contains a number of waterrelated constellations. To the east, southeast and south of the Great Square sits Pisces, the Fish, most notable because of the Circlet located south of the Great Square. Southwest of Pisces lies Aquarius, the Water Bearer. Although generally brighter than Pisces, Aquarius is a large, sprawling and ill-defined constellation. The most prominent pattern here is the Water Jar, sometimes referred to by its more contemporary title: the Steering Wheel. Southwest of Aquarius is Capricornus, the Sea Goat. This is a very ancient constellation that resembles a southpointing triangle. If you struggle to see this, look for Mars, as the Red Planet is passing eastward through Capricornus. The watery theme continues southeast of Capricornus and south of Aquarius with Piscis Austrinus, the Southern Fish. The brightest star here is Fomalhaut, the most southerly first-magnitude star in the sky as seen from the UK. An easy way to locate Fomalhaut is to extend the line made by the western side of the Great Square of Pegasus south. If you do this, you’ll eventually arrive
Þ Both Northern and Southern Taurid meteor showers peak under favourable conditions. Both have a low ZHR of five meteors per hour, but have shown good fireball activity in the past at Fomalhaut, assuming it’s not hidden by a foreground object such as a house or tree!
Heroes and monsters South of Pisces is Cetus, the Whale/Sea Monster, another large and sprawling maritime constellation. This pattern is odd because its outline, as shown on star charts, looks like a whale with a tail to the northeast and nose to the west. But seeing it this way round, the brightest star in the supposed tail is orange Menkar, a name Distant Uranus reaches opposition on 24 October and should just be visible to the naked eye from a dark site
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that means ‘nostril’. The brightest star close to the whale’s supposed mouth is Deneb Kaitos, which means ‘whale’s tail’. So what initially looked like a west-facing whale is actually the wrong way round. Returning to the Great Square of Pegasus, a wedge-shaped pattern spreads out from its northeast corner. This is Andromeda, the Chained Princess. Just north of the middle of the wedge’s northern edge you’ll find the Andromeda Galaxy, M31. Its faint, elongated smudge is the furthest thing you can see with your just your eyes under normal conditions. It lies a staggering 2.5 million lightyears away. Andromeda stretches east towards her mythological husband, Perseus, the Greek Hero. Perseus contains the eclipsing binary star Algol, which appears to dim every two days, 20 hours and 49 minutes. In mythology the Gorgon Medusa had a stare capable of turning any living thing into stone. Perseus cut Medusa’s head off and revealed it to Cetus to save Andromeda, who had been chained to a rock as a sacrifice to the sea monster. Algol is supposed to represent the Gorgon’s eye and is also known as the winking demon. The ‘W’-shaped pattern to the north of Andromeda is Cassiopeia, the Seated Queen. She and her husband, king Cepheus, represented by a house-shaped pattern to the northeast of Cassiopeia, are Andromeda’s parents.
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