Countdown to Astroblast 2008

Less than three weeks to go and preparations for Astroblast are coming along well. It promises to be a great day with lots to interest everyone from the complete beginner to the experienced observer.

There are details on the Astroblast Web Site including speaker and talk list, timings for the planetarium shows, and a list of participants. There will be a lot happening, including live firing of a rocket motor in one of the talks, an amazing presentation on Saturn, and, weather permitting, a demonstration of radio-controlled rocket gliders by the Great Britain Team. There will be several workshops running throughout the day, some aimed at children and some for adults that will help people get started in astronomy and astrophotography.

Food and drinks will be on sale on the day by Friends of Everton Cubs who run a superb outdoor barbeque. If you prefer a three-course cooked lunch in the school dining hall these are available but must be booked in advance. See the web site for details or call 01954 211288 to book them.

Please mention Astroblast to your friends, acquaintances and especially to your local school and teachers. You can download a poster from the Astroblast web site to print out if you wish. Alternatively, click here to download it .

Astronomy for Absolute Beginners

This popular one-day course will be held this coming Saturday in the board room at Scotland Farm (just across the road from Green Witch). There are places available so please call us if you would like to attend. The cost is 30 pounds and it runs from 10 am until approx 4 pm. Meet at Green Witch at 9:45 am.

Whirlpool Star Party

Lucy and I attended the Whirlpool Star Party at Birr in County Offaly, Ireland, my first visit for a few years and the first time we have taken a trade stand. As always, the Irish reception was very friendly and we had a most enjoyable weekend. We travelled by fast ferry from Holyhead with a car load of equipment and despite the long drive this proved a comfortable way to travel.

If you've not seen Lord Rosse's Great Leviathan then I recommend you put the Whirlpool in your diary for next year. The telescope is set in the delightful grounds of Birr castle, known as the Desmesne, and there is an excellent scientific exhibition covering the pioneering work that led to the construction of the telescope, the early photography undertaken by the Third Earl's wife, and the history of the Parsons Family. This can be traced down to Grubb Parsons who built many major telescopes including the William Herschel on La Palma.

Earth being Bombarded?

I've heard anecdotal reports of a few fireballs in the last couple of weeks followed by an announcement on the morning radio that an asteroid had been detected that was just about to hit the atmosphere over the Sudan.

Meteosat subsequently observed and recorded the flash caused by the impact of Asteroid 2008 TC3, exactly where and when predicted. A KLM airliner that had been alerted to look for it also saw the flash from about 1400 km away. Ground stations in Kenya picked up the infra-sound signals caused by the impact which was estimated to be equivalent to be between 1.1 and 2.1 kilo-tons of TNT, ie a small atomic bomb.

Apparently several asteroids of this size, about the size of a car, hit the atmosphere each year, but this is the first one to have been detected before impact. Astronomers at Mount Lemmon in Arizona found it as part of the Catalina Project on Near-Earth Objects.

Astronomical Sketching

Jeffrey Barham sometimes brings in sketches of craters on the Moon that he has made at the telescope. They are very good and I've often wished I could do something as good, but I've never tried. At the Whirlpool Star Party two delightful ladies, Sally and Dee, gave a talk on their sketching then ran a short workshop on how to do it. Lucy and I had a go, copying from photographs, and I was amazed to produce something recognisable and much better than I expected.

I will give it a try at the eyepiece but the thing I really noticed was how much more closely I looked at the photo when I was trying to copy it. I am sure that sketching a small portion of the Moon, say a couple of craters, will encourage you to look much more closely and become a better observer.

There is a new book in the Patrick Moore Practical Astronomy Series called Astronomical Sketching which I plan to read. I am told that it gives a good introduction to sketching, especially for the Moon, Sun and planets. If you are a sketcher and can copy your sketches into electronic form I would like to publish some on our web site to encourage others to give it a try.

Protecting Your Telescope

While Lucy and I were at the Whirlpool Star Party, Lee was at the Kelling Sky Camp where he enjoyed some good observing, but coupled with a very heavy dew. In fact, conditions became so wet that several unfortunate people suffered damage to their telescope electronics and laptop computers.

The only answer to these conditions is to cover up your equipment to prevent the water getting into it. This is where the Green Witch scope cover comes in handy, and Lee quickly sold out of the stock he had taken with him. Quite a lot of other people had their Green Witch scope covers with them and it seems they are very popular. We are quite pleased as we spent a lot of time finding a suitable cover at a reasonable price. You can find them here on our web site .

Christmas Recommendation

If you know anyone thinking of buying a first telescope for Christmas then why not suggest they take a look at the SkyMax 127 Supa-Trak. With 5-inch Maksutov-Cassegrain optics it is quite a serious telescope, but is compact and comes on a simple alt-az mount with built-in motors for tracking and guiding.

It is much easier to set up than a German equatorial mount and is easier to handle. Once aligned it will track any star that you point it to. You can see it on our web site under the Recommended Starter Scope section. Just scroll down to the best buy.

Baader Planetarium Accessories

We've been impressed by the quality and value of all the Baader accessories we've tried. They make a good range of filters, especially the UHC-S and Oxygen III filters for deep-sky observation. The UHC-S is probably the most popular quality deep-sky filter we sell, and it performs as well as some other filters costing twice as much.

Baader Astrosolar film is well-known for white-light observation of the Sun and has become most people's first choice. You will find it in many ready-made filters from other manufacturers but it is easy and cheap to make your own filter from an A4 sheet. Sunspots are starting to reappear so now is a good time to equip yourself with a solar filter.

The new Baader Click-lock 2" Dielectric Star Diagonal combines an excellent mirror with a very quick but effective means of locking your eyepiece or accessory in place. A simple lever locks and releases the eyepiece and the connecton will support quite heavy accessories. As a key element in your optical train, upgrading to a high-quality diagonal can make quite a significant improvement to your image quality.

Bino-viewers are becoming more popular and Baader make one of the most versatile. It is available with a 1.25 or 2-inch fitting, or with an image erector and glass-path corrector for terrestrial viewing. Don't be put off by thinking that you need to double up on all your eyepieces. Start with the eyepiece you use most often and buy a second one. When you get used to using this you can decide which if any additional eyepieces you want to buy.

I recommend taking a look at the Baader Accessories Section of our web site. We'll be adding to this as new products become available and we check them out.

Build Yourself an Orrery

Orreries are named after the 4th Earl of Orrery and are mechanical models showing the movements of planets in the solar system. We've just discovered a model you can build for yourself which shows the motions of Mercury, Venus and the Earth and Moon. It's in the same range as the Stirling Engine and other kits we currently sell. These have proved very popular and are good value.

You may have seen a magazine advertised on TV that comes with part of an orrery in each issue to enable you to collect and build your own. If you work out how much the orrery will end up costing it is quite substantial. Our orrery costs much less and you get it all immediately. It makes an ideal gift and you can find it in our Astromedia Section. (The instructions have been translated properly into English from the original German, as is the case for all the models.)

Astronomy Books

With Christmas on the horizon now is the time to start dropping hints and there are four books from Cambridge University Press that you might like to consider. We will be matching Amazon's price on them so they will be good value. All are hardbacks so are gifts to use and treasure for a lifetime. Written by Steve O'Meara they make an excellent set describing over seven hundred deep-sky objects. You can find them here on our web site .

Looking South at 11 pm from Cambridge, UK

The Great Square of Pegasus sits astride our meridian with its centre about 60 degrees above the horizon. It is easy to spot provided you are looking for something of the right size. The sides of the 'square' vary between 13 degrees and 16.5 degrees approximately, so if you spread your fingers at arms length expect the sides to be about the distance between the tips of your index and little fingers.

Only three of the stars are officially in Pegasus. The top left one is actually alpha-Andromedae and is usually depicted as her head. It's also called Alpheratz or Sirrah, both of which apparently mean the horse's navel. I'm not sure Andromeda would be flattered to hear that her face was also a horse's navel.

Despite its size, the Square of Pegasus contains few stars bright enough for the naked eye, and the bright Moon off to your left may make it hard to see any. But on a clear, dark night you might like to see how many you can count. Compare notes with friends and try this on different nights.

Below the square lies the head of Pisces the fish, one of the signs of the Zodiac, so the ecliptic, the Sun's apparent path, runs through it. Just to the left and a little lower than the head lies the point where the ecliptic crosses the celestial equator. This is sometimes known as the First Point of Aries because it was in Aries when first defined. The reason it moves is that the Earth's axis wobbles around like the axis of a giant spinning top. Taking approx 26,000 years for one cycle it spends around 2,000 years in each sign of the Zodiac.

If you are old enough you may remember the 1967 musical 'Hair' and its opening song called Aquarius. This spoke of the dawning of the Age of Aquarius and referred to the fact that the First Point of Aries had moved a long way across Pisces and would soon be entering Aquarius. It was supposed to occur around the end of the 20th century and would usher in an era of peace and enlightenment. We're still waiting.

Uranus is just below the head of Pisces but a little to the right of our meridian. Although it is bright enough to be seen with the naked eye in very good conditions it wasn't discovered until 1781 by William Herschel. You should be able to see it easily in binoculars on a clear dark night and it is just big enough to distinguish from a star with good optics. However, finding it will be difficult without a good star chart and I usually use SkyMap Pro to produce a suitable finding chart. When the Moon moves away why not try to find it for yourself?

Close to the horizon and about ten degrees to the right of our meridian you may be able to see the bright star Fomalhout in the constellation of Piscis Australis. It is about 30 degrees south of the celestial equator so is quite a long way into the other half of the sky. You will need a clear southern horizon as it doesn't venture far above it.

And Finally...

I was pleased to hear that several councils are considering switching off street lights for part of the night to save money. This is good news from many points of view and will help to give us back one of the most over-looked sites of outstanding natural beauty, the night sky.

Objections to the idea usually revolve around security but councils who have tried the switch-off have generally experienced a drop in crime. The way forward is to use the right light in the right place at the right time. There is good advice about this from the Campaign for Dark Skies and on the Home Office Crime Reduction web site. If you have what I call 'insecurity lighting' why not replace it now with something more environmentally friendly and more effective?

Clear Skies and Best Wishes

Neil

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www.astroblast.org.uk
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