Astronomy Know How
Helping you See the Night Sky - Newsletter No. 23 September 2008
In this issue:
September brings dark skies noticeably early now and with it a wealth of things to see in the night sky.
The Autumn (or Fall if you prefer) equinox arrives on the 22nd of this month when the Sun enter the southern celestial hemisphere. The word 'equinox' means equal day and equal night, so we get 12 hours of daylight and 12 hours of darkness. It also means that, for those in the northern hemisphere the night will increasingly become longer. Arguably a good thing for us astronomers!
This month brings us the Piscid meteor shower. Not a particularly active shower or very bright meteors, but worth looking out for in a clear dark sky. The ZHR (Zenithal Hourly Rate) is around 10 meteors per hour.
The elusive planet Mercury is on show this month when it reaches its greatest eastern elongation on the 11th. However, due to the angle at which we can view it from here on Earth at the moment it is not particularly well placed, being quite low down and near to the horizon just after sunset. So you are going to need a clear horizon and good visibility if you have any hope of seeing it. Helpfully, Venus is going to be close by, which might help you locate it, as Venus is considerably brighter than Mercury. If you are planning to use binoculars or any other optical aid, make sure that the Sun has properly set before sweeping for it around the western horizon.
Jupiter is also on show this month, although it is now rapidly disappearing from our view in the northern hemisphere. Look out for the four Galilean moons as the perform their nightly dance about the planet. Also, see if you can see the great red spot on the planet's surface. You will of course need a small telescope for this and you will certainly be rewarded with stunning views, in spite of the planets low altitude.
The planet Uranus comes to opposition this month, that it is opposite the sun in the skies from our perspective. This happen on the 13th of the month and it can be found in the constellation of Aquarius. You will almost certainly need a star chart and at least binoculars to be able to find it unless you have exceptionally dark skies.
The Stars of Early Autumn
September brings us darkness noticeably earlier than in August and with it a greater opportunity to go observing! If you are familiar with the stars of the summer triangle (Deneb, Altair and Vega), you see them now sinking towards to western horizon by mid-evening in the middle of the month, to be replaced by the square of Pegasus now hanging high in the south.
If you have a clear southern horizon then now is the time to see if you can spot a star in a constellation normally only visible from the southern hemisphere. This is the star Formalhaut or alpha Pisces Austrinus and is the southern most visible star of first magnitude (very bright) available to be seen from mid-northern latitudes. You can find it by dropping an imaginary line down from the right hand or western-most stars of the square of Pegasus. THe bright star that you come to just above the horizon is formalhaut.
Just below the square of Pegasus you can find the 'watery' constellations of Aquarius (the water carrier), Pisces (the fishes) and Cetus (the whale). Directly below the Square of Pegasus you can find the asterism - another name for a familiar group of stars - of the 'circlet'. this is one of the fishes of the constellation of Pisces, which is tied by a cord (I can't imagine why) to its twin that can be found off the left or east of the Square of Pegasus. To the west (right) of the 'circlet' can be found another asterism, this time in the constellation of Aquarius. This one is the 'water jar' or to bring it up to date the 'steering wheel'. It does look more like a a steering wheel than a water jar! Finally, if you drop another imaginary line from the left or eastern-most two stars of the Square of Pegasus, you will come to the star Deneb Kaitos or beta Ceti the second brightest star in Cetus. Again, this is very low to the southern horizon and you will need a clear view in order to see it.
Andromeda on Display
Everyone seemingly wants to be able to see the Andromeda Galaxy, but many people have difficulty in finding it. I hope that this guide might help you track it down...
The constellation of Andromeda is a little like a distorted letter 'V' that has its point at the top left star of the Square of Pegasus. This is in fact the star alpha Andromedae also known as Alpheratz. If you take the left hand 'fork' of the 'V' of the constellation and move up two stars, you will come to a reasonably bright star that is beta andromedae and is the second brightest star in the constellation. Now head right or westwards and you should see another bright(ish) star. If you then draw an imaginary line between these two stars and keep heading westward you should pick up a fainter but still noticeable star and next to it a faint fuzzy patch. You've found it! If you are observing from a light polluted area then binoculars will help you find your quarry. This fuzzy patch of light is the Andromeda Galaxy and is the furthest object that can be seen (from a dark site) with the naked eye.
Binoculars will show this object to best effect as it is really quite large although it is faint. If you would like to find out more about how to find and observe such beautiful objects then I can recommend my online course 'Basic Astronomy With A Telescope', as recommend by no less than Sir Patrick Moore. You can find out more at www.astronomy-course.com
Lunar Occultation of Neptune
In the early hours of 13th September the Moon will pass in front of the planet Neptune for observers based in the UK and northern Europe.
Neptune is quite faint, so you will definitely need binoculars to witness this event. The action takes place quite low down in the western skies at around 02:00hrs UT (universal time - similar to GMT). Over the next 30 minutes you should be able to make out the tiny disk of Neptune being 'stalked' by the moon approaching from the west. As the dark limb of the Moon passes in front of Neptune it will appear to 'wink out. Unlike a star it will not vanish instantly but take a few seconds as the Moon occludes its disc.
Neptune should reappear some 25 to 30 minutes later depending on your observing latitude. Enjoy the show!
Photographing the Night Sky with a Digital Camera
If you are the proud owner of a Digital SLR camera, then you can use it to taking amazing images of the night sky!
Everything that you need to know to get started will be in a new eBook that I am writing, which you can download from the internet. It's written in a friendly and accessible style and answers many of the questions that beginners to the subject usually ask.
It is co-authored with my friend and talented astro-imager John Walton and will come with some superb bonuses that I think will frankly amaze you.
We are now set for publication in mid September. So if you would are interested in this eBook, keep checking your emails, as we will be notifying all our 'newsletter' readers first so that you can take advantage of the introductory discount!
Here are some links to some other recent news stories that I thought you would find interesting...
Hubble Telescope Spies Magnetic Monster in Erupting Galaxy
Greenbelt, Maryland - NASA's Hubble Space Telescope has found an answer to a long-standing puzzle by resolving giant but delicate filaments shaped by a strong magnetic field around the active galaxy NGC 1275. It is the most striking example of the influence of the immense tentacles of extragalactic magnetic fields, say researchers. more...
Teacher finds new cosmic object
A new class of cosmic object has been found by a Dutch schoolteacher, through a project which allows the public to take part in astronomy research online. more...
Medieval astronomy tool helped tell time
A rare astronomy tool that helped medieval scientists tell time will remain in Britain after the British Museum scrambled to come up with the money to buy it. more...
Shuttles Will Not Fly Earlier
Managers on NASA's space shuttle, International Space Station and Hubble Space Telescope programs have decided not to advance launch dates for the two shuttle missions remaining this year. more...
Do you want to learn more about the night sky and how
to use telescopes and binoculars to see it better?..
My online course gives you all the essential information to be a good astronomer, without lots of jargon or difficult maths. You'll get loads of free bonuses and it also has videos and animations to help make the explanations clear and concise. So if you want to know what Sir Patrick wished for...
...please take a look at my eCourse called 'Basic Astronomy with a Telescope'. It's what Sir Patrick wished he'd had when he started out in astronomy!
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