The Night Sky in October 2005
Looking at the night sky with the naked eye or using a telescope is fascinating and each month these notes keep you up-to-date with unfolding events.Maps of the current night sky can be see by clicking HERE
Phases of the Moon
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| New Moon Monday 3 |
First quarter Monday 10 |
Full Moon Tuesday 18 |
Last quarter Tuesday 25 |
Click HERE to see the phase of the Moon on each day of the month.
Monthly Highlights
As we slowly creep towards winter we will gradually see less and less daylight. The good news is that we don't have to stay up too late to get a good look at the night sky. The same is true for the Liverpool telescope, which is sited in the Canary Islands, except that the nights are much darker and clearer - perfect for requesting images of astronomical objects using Go Observing.
October 3rd - Total annular eclipse of the Sun
Annular eclipse of the Sun
Early on the morning of 3rd October there will a total annular eclipse of the Sun visible across parts of Portugal, Spain and North Africa. An eclipse occurs where the Moon passes in front of the Sun and blocks out some of the sunlight, causing it to go dark for a few minutes. In other words, we pass through the shadow of the Moon. A total annular eclipse is one where the Moon is directly in front of the Sun but is not large enough to block out all the light, such that a ring of brightness remains around the Moon. At most, around 90% of the Sun's light will be blocked out during this eclipse, even from the best viewing locations.
From the UK, we will only be able to see a partial eclipse of the Sun because we do not lie directly beneath the Moon's path, thus only around 60% of the Sun's light is blocked out. Remember, you should never look directly at the Sun because it can easily damage your eyes. It you want to view eclipses, you need special glasses and equipment - ask your teacher for more details. If the weather is clear and you want see the eclipse then you will need to bear in mind the following times -
London 08:49
Manchester 08:50
Edinburgh 08:53
Last Contact (when the Moon stops covering the Sun)
London 11:18
Manchester 11:15
Edinburgh 11:13
If you didn't get to see the eclipse this time then don't worry .... another one will be visible on the 29th March 2006. If you want to learn more about eclipses then follow this link .
October 21st - Orionids Meteor Shower
Halley's Comet
At certain times of the year, the Earth passes through a trail of dust and debris that was left by a passing comet many years ago. When it does so, we see an increase in the number of meteors or shooting stars as this debris collides with and burns up in the Earth's atmosphere. When these events occur they are known as meteor showers and are often quite spectacular to behold. The cause of the Orionids is actually the most famous of comets, Halley's Comet, which orbits the Sun every 76 years and has been recorded by astronomers since 240 BC, making its last appearence in 1986.
The left-over comet trail is quite extensive; so although there's an increase in the number of meteors from the 15th October onwards, the peak of the Orionid meteor shower occurs on the evening of the 21st October before reducing again toward the 29th. During the peak, you can expect to see in the region of 20 meteors per hour. These will appear to originate close to the star Betelgeuse in the constellation of Orion. We learnt how to find Orion in last December's night sky article. Unfortunately, the Moon will be close to full around that time, so may hide some of the fainter meteors. Best viewing will be toward the east after midnight.
The Planets
Click HERE and start the Electric Orrery to see where all the planets are today in relation to each other.
MercuryMercury starts the month as a rather dim evening 'star', remaining low in the west for about 20 minutes after sunset. As the month moves on, Mercury's visibility improves and it remains longer in the dusk sky as it moves towards us in preparation for passing in front of the Sun. Mercury reaches maximum separation from the Sun during the first week of november, so should remain visible throughout the month. Why not try confirming this using the electric orrery to track its orbital motion during October.
VenusVenus remains clearly visible as a brilliant evening star and will continue to increase in size as it moves closer to us, although it's brightness will change little. It may be seen low toward the west-northwest for a little over 60 minutes after sunset, shining brighter than all the other planets. Remember that planets appear to shine steadily in the night sky, whereas stars tend to twinkle; that's how we can tell them apart. Towards the middle of next month, Venus will slowly start to make its way in front of the Sun as it undertakes us.
MarsMars continues to become more prominant, rising toward the east-northeast around 90 minutes after sunset. This moves earlier into the evening as the month progresses and we slowly start to overtake it on the inside. On October 30th, Mars will be at its closest point to us for the next 13 years. Why not check this using the electric orrery. Although it can be seen with the naked eye, Mar's salmon-pink or orange colours will be far more vivid through binoculars or a telescope. Now is by far the best time to look at Mars using the Liverpool telescope, as you should be able to make out some surface features!
JupiterJupiter can just about be seen in the western sky for about 30 minutes after sunset. This reduces sharply as Jupiter moves behind the Sun. In truth, because Earth's orbit is much shorter than Jupiters (1 year as opposed to just under 12 years), it is us that is moving behind the Sun, and as a result Jupiter will soon disappear from view for a few weeks. It will be at superior conjunction (opposite side of the Sun to the Earth) around October 23rd and will unfortunately not be visible to the Liverpool telescope again until the beginning of next year.
SaturnSaturn rises shortly after midnight towards the east-northeast and is currently passing through the constellation of Cancer. Although it remains dim to the naked eye, Saturn is once again starting to become a reasonable target to observe with the Liverpool Telescope using Go Observing. However, the beginning of next year should provide the best opportunity to observe this gas-giant planet, and with Saturn's rings remaining open throughout the period, any images should be quite stunning.
Constellation of the monthEach month, new constellations are highlighted for you to identify in the night sky.This month, we are going to see if we can find the constellations of Pegasus, the winged horse of the gods, and Andromeda, named after an ancient Greek princess. The constellations are adjacent to each other and can be seen high in the southern sky close to midnight.
 October Night Sky You can easily identify the constellation of Pegasus by looking for four bright stars which make up the shape of a box, known as the Great Square of Pegasus. From there it should be fairly straight forward to identify the line of stars that make up Andromeda. The most notable feature of Andromeda is that it hosts the nearest spiral galaxy to our own galaxy. The Andromeda Galaxy, better known to astronomers as M31, is thought to be very similar in nature to our own Milky Way. As a result, it is the most studied of all the other billions of other galaxies out there in the Universe.
 The Andromeda Galaxy M31 is just about visible to the naked eye if you look carefully enough, although it helps if you are observing from somewhere with dark skies. It appears as a large fuzzy blob in the location marked in the Sky Map above (green circle) and is easier for your eyes to pick up if you look just to one side of it. With binoculars, you should be able to see more shape to the galaxy. Mythology: Andromeda Andromeda was the beautiful Princess of Ethiopia, daughter of Cepheus and Cassiopeia. Cassiopeia was a vain woman who claimed that her daughter was more beautiful than the sea nymphs, the Nereids. Insulted by this, the Nereids complained to Poseidon, god of the sea, who sent a flood and a sea-monster, the Kraken, to destroy the Kingdom in order to avenge his nymphs. The King, Cepheus, was advised by the Oracle, Ammon, to sacrifice Andromeda to the Kraken by chaining her to a sea cliff to be devoured by the monster. Chained in this way she was seen by Perseus, fresh from slaying the Gorgon, Medusa. At first he thought Andromeda was a statue, but when the wind ruffled her hair and Perseus saw she was crying he fell instantly in love with her. Dazzled by such beauty, he stopped and asked her her name, and why she was there. At first she did not reply as it was not the custom in those days for a girl to speak to strangers. When Perseus asked her again and again how she came there, she became afraid in case her unwillingness to answer might make her seem guilty; so she told him her name, where she came from, and how her mother, a beautiful woman, had been too vain. Before she had finished telling Perseus these things, the waters roared and the Kraken arose from the sea. Andromeda screamed. Perseus told Cepheus and Cassiopeia that he would kill the monster if they let him marry Andromeda. They, of course, agreed. Perseus then killed the monster by holding up the head of Medusa, thus turning it to stone. Andromeda was set free, and later married Perseus. After the wedding, Andromeda left her country to live with Perseus who later became King of Tiryns and Mycenae. The Goddess Athena placed the image of Andromeda among the stars as a reward for keeping her parents' promise.
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