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Welcome to the October edition of Eyes on the Night Sky, where we select some of the best astronomical highlights for the month. Darkness falls earlier in the evening, so you don’t have to compromise on sleep to stargaze! The Milky Way emerges into the south-west as evening falls and will look spectacular in a dark sky, away from light pollution. Read on to find out what else there is to discover in our beautiful night skies.

Two Full Moons

There are two full Moons this month: the first occurs on 1st October, traditionally known as the Harvest Moon and the second on 31st October, known as the Hunter’s Moon, or Blue Moon, as it’s the second full Moon to occur in a month.

The New Moon falls on 16th October. 


The Orionids

Earthgrazer ©Sean Weekly

An earthgrazer over Craig Goch Dam ©Sean Weekly

The Orionid Meteor Shower peaks in the late night of 20th October and early morning of 21st October. There will be no Moon in the sky to interfere, so you may see up to 20 meteors per hour. Even though the ‘shooting stars’ are relatively faint, they do leave persistent trains of ionised gas.

In addition, as the radiant occurs near the Constellation of Orion which rises from 10.45pm, you may see rare Earth Grazers. Meteors skim the surface of our atmosphere like a flat stone travelling over the surface of water. From the low position on the horizon, they travel horizontally overhead, which is why they appear long and bright. 

Two Conjunctions

Moon/Mars Conjunction on 6th September 2020 ©Allen Lloyd

If you missed the Moon/Mars conjunction last month, you will have a second chance to see the Red Planet in very close proximity to the Moon.

On 3rd October the Moon and Mars will only be separated by 1.1°. Look south-west at around 6am to see this lovely sight. If you have a telescope, take some time to spot Mars’ white, polar ice cap, which contrasts nicely with the planet’s red surface.

On 22nd October, a second close encounter will occur where the Moon and Jupiter will be separated by 2.9° distance. It is a pleasing sight in the early evening sky. Look to the southern skies and try to spot Saturn trailing by the pair. Binoculars will reveal Jupiter’s moons and it’s always a treat to study the terminator of the Moon, where the shadow meets its illuminated features.


Constellation of the Month – Taurus

This month, we will look at the mythology behind the Constellation of Taurus the Bull. Rising in the North-eastern sky at around 8pm, you will see the stunning Pleiades Cluster with the rest of the constellation following. Look for the sideways ‘V’ asterism comprising five stars which is below the Pleiades Cluster. If you are under a rural sky, you will also notice the two ‘legs and arms’ of the constellation radiating from four positions from the ‘V’. The two left hand ‘legs’ are the Bull’s horns and the ‘V’ represents its head.

In Greek mythology, this bull represents Zeus. In his attempt to woo Europa, the beautiful daughter of King Agenor, Zeus became a bull and joined the royal herd of cattle. Europa noticed Zeus grazing and decided to sit on his back. Zeus whisked Europa over the Aegean Sea to Crete. One they reached their destination, he revealed his true identity and bestowed Europa with an abundance of lavish gifts. She fell for this and the pair had three sons together and lived happily ever after. In tribute to his life, Zeus placed the bull in the sky.

If you have binoculars or a telescope, look for a recent supernova fragment called the Crab Nebula, or Messier 1, which lies 6500 light years away. In binoculars under a dark sky, it will appear as a faint, grey blob and will appear to be brighter through small telescopes. Larger telescopes of 12 inches and upward may reveal its filamentary structure.

Credits: NASA, ESA, J. Hester and A. Loll (Arizona State University)

This nebula is a fairly new one; discovered in 1054 by Chinese astronomers, who saw an unfamiliar star among the constellation of Taurus, which was a supernova (exploding star at the end of its life). Historical records stated that this new star was brighter than Venus and was the third brightest object after the Sun and Moon. This spectacular sight lasted for three weeks and faded significantly over the next two years. There have been other accounts of this unusual phenomenon from other areas of the world at the time.

The nebula was not discovered until 1731, when John Bevis noticed a cloudy blob through his small telescope and comet hunter Charles Messier independently discovered it about 20 years later, adding it to his catalogue of objects that were not to be confused for comets. In 1844, the third Earl of Rosse studied it through his huge 34 inch telescope and compared it to a crab’s back, hence its name.

On 25th October at 2am, British Summertime ends, so adjust your clocks back by one hour.