“Double Hubble toil and trouble…” -While some stargazers will recognise the slight liberty taken with the witches’ famous words in Shakespeare’s ‘Macbeth’, more than a double take of Hubble telescope images should help us decorate our night sky for the month that hosts Hallowe’en.
Perhaps the most interesting direction this month to find some constellations on show, is in the east. To commence this month’s star hunt therefore, position yourself looking towards where the Sun rises in the morning as we look for the constellation of Andromeda the princess. This fair celestial maiden of myth had no easy ride to earn her place in the heavens. Her easily most distressing life experience was brought about thanks to the behaviour of her apparently not-so-loving mother, Queen Cassiopeia. When some divine wrath began to lay waste the shores of her father’s kingdom and the royal household sought the solution from an oracle, they were informed that a human sacrifice, namely Andromeda could appease the perpetrator’s vengeance. Instead of an outright refusal, Cassiopeia ordered her daughter be chained to a rock to be served up to the beast as requested. However before being devoured by the creature a newcomer on a winged horse entered the scene, Perseus.
Although initially being too shy to speak, the reality of her desperate situation soon had Andromeda pouring out the details of her terrible plight to this ultimately heroic stranger. When the beast eventually emerged the princess chose to mark the occasion, rather understandably with an ear-splitting scream. So what do we think: was she eaten? Of course not! -while some of the Greek mythology concerning the heavens can have dark and turbulent undercurrents, this one in particular has a truly happy ending. After somewhat predictably achieving her deliverance, Perseus was rewarded with Andromeda falling in love with him and being offered her hand in marriage. Although there are the usual variations between how some astronomers choose to connect the stars within this constellation, a popular way to recognise Andromeda in space is to look for a capital letter ‘A’ lying on its side, with the top of the ‘A’ pointing like an arrow to your right. This star is called Alpheratz. It in fact forms the top left hand corner star of a useful heavenly marker, the Great Square.
Where one light year presents 9.5 trillion kilometres, the most distant naked-eye dark sky object in space is Messier 31, the Andromeda galaxy, located an incredible 2.5 million light years away. With clear skies look just above and halfway along Andromeda’s side to see its small grey ellipse.
Moving down in the east one step nearer to the horizon we come to a somewhat aquatic star pattern, Pisces the fish. While the first fish is swimming up just beneath Andromeda and depicted with a narrow ribbon of stars running down from its tail to the horizon, this challengingly-obscure star pattern then forks off toward the south with a vaguely ‘V’-like formation of stars to reach the second fish. But, why fish? Well according to myth when the dragon-headed storm god Typhon was once again terrorising the neighbourhood, the fish symbolised the two fish that brought the goddess of beauty, Aphrodite (or Venus) and her son Eros (or Cupid) from their precarious hiding place in the rushes of the river Euphrates to safety. Approximately halfway down the left-hand fork of the ‘V’ of Pisces and beside the star Eta keep your eyes peeled for M74, a galaxy whose galactic disc we ‘look down on’ from Earth and in which we can therefore clearly view its wide-open spiral arms.
The Egyptians believed that this next celestial character was responsible for the annual flood of the River Nile, Aquarius ‘the water carrier’. You will find Aquarius’s pattern of stars just to the right of Pisces’ south-facing fish. Often depicted as a handsome youth pouring water from a pitcher, he is generally recognised as the son of the king of Troy, Ganymede who was chosen to be a cupbearer in the court of the god-king Zeus. With a theme of water pervading all the constellations in the celestial vicinity the Babylonians claimed that Aquarius was in charge of them all.
Now however let’s take a short break from stars, constellations, and planets, and try and track down some nebulae that appear to have a chilling affinity with the spirit of Hallowe’en! First up, with the aid of the Hubble telescope and our mind’s eye we may just spot some space gremlins perched on the brim of a witch’s hat 1200 light years deep within the constellation of Cepheus. This tiny star-forming nebula SH2 136 comes complete with dark dust and what appears to be two mischievous ‘dust devils’.
If we then turn our eyes to the constellation of Taurus a cosmic den of iniquity could well be lurking beyond these stars! Just as if some sinister spotlight were catching the top of its shroud, what looks very like a towering hooded phantom can be seen with its orange-eyed ghoulish stooge, holding vigil upon some shadowy peak in the reflection nebula IRAS 05437 + 2502.
One of the most formidable foes of fiction existing in space? “The eye was rimmed with fire, but was itself glazed, yellow as a cat’s, watchful and content, and the black slit of its pupil opened on a pit, a window into nothing.”-J.R.R. Tolkien. In astronomical terms the current explanation of this recently-discovered 266 Earth-Sun-distance wide (AU) space object is a debris ring and an excess of infra-red radiation from the star and extra-solar planetary system, Fomalhaut. However to those familiar with J.R.R. Tolkien’s ‘evil eye of Middle-Earth’ from The Lord Of The Rings, to all intents and purposes they will be disturbed to recognise it as the eye of Sauron, apparently revealing his malevolent presence in space.
If we look down one of space’s deep dark alleys with a good telescope, in the constellation of Orion we will see emerging from the gloom, the vast, eerie form of a witch’s head… no kidding! Even professional astronomers tell us so, and for that reason have named the object ‘The Witch-head Nebula’. Her creepy bluish pallor is generated by illumination of this cosmic cloud of gas by the adjacent blue hypergiant star Rigel.
While we keep our observational powder dry for next month let’s take a sneak peek at Sun-grazing Comet ISON, now estimated to slingshot round our Sun next month at more than 1 000 000km/h!
So “Double Hubble toil and trouble…”! As you raise your eyes to the heavens to observe the great sights of the night sky in October, happy hunting and enjoy your interstellar voyage!
(Article by Nick Parke, Education Support Officer)