Astroblast 2008 - Space and Astronomy Fun Day for all Ages

With less than two months to go the preparations for Astroblast are progressing well. I've updated the web site at www.astroblast.org.uk to show some of the participants. These are being added to all the time. The date is Sunday 2nd November 2008; the venue is Bedford School; the time is 10 am to 4 pm and entry is free. We hope you can join us for what will be a great day out.

Astronomy for Absolute Beginners

Dr Jeffrey Barham will be giving his popular one-day course for astronomy beginners on Saturday 18th October. Meet at the Green Witch Showroom at 9:45 am for a good basic introduction to the subject.

You can find details here on our web site or give us a call on 01954 211288.

Two Eyes are better than One.

Have you considered enhancing the pleasure of using your telescope by adding a bino viewer? These are becoming increasingly popular, especially since their price has fallen along with the price of eyepieces. It's no longer prohibitively expensive to duplicate your favourite eyepieces for the bino viewer.

Everyone we know who has purchased a bino viewer says the same - it makes observing so much better. The brain does a very good job of combining the signal from both eyes to produce a better view than each eye alone can give. Minor defects in each eye do not affect what you see. And keeping both eyes open is so much more comfortable and less tiring than keeping one closed.

If you can use binoculars then I recommend the Baader Bino Viewer which you can find here on our web site. If you are working on a more constrained budget then the Bino Viewer from Optical Vision is very good value. It is shown below the Baader.

Green Witch now sells Takahashi

You have probably heard of Takahashi Telescopes. They have a reputation for producing outstanding refractors and are considered to be right at the top end of the quality range available commercially. But they also produce high quality catadioptric telescopes and mounts.

We are now an authorised Takahashi dealer and can supply any of their range. You can see some of their equipment in the Takahashi Section on our web site. At the time of writing I still have a lot of work to do adding the accessories but please feel free to contact us if you have any questions or need anything that is not yet shown.

Why not join Moon Watch?

Astronomers usually regard the Moon as a niusance if it's in the sky during a meteor shower. But some astronomers have taken to observing the night side of the Moon during showers to watch for the impact of meteors on the lunar surface. According to an article on the NASA web site, an 8 or 10-inch telescope is sufficient to see the flash produced by the impact.

You can read the article here. It describes the equipment being used and the results obtained. If you like the idea of monitoring the Moon for meteorite impacts you could contribute to the safety of the next manned mission to the Moon.

High Quality Refractors from Meade

Back in June I mentioned the 127mm apochromatic ED refractors from Meade. At that time there were very few available but a new delivery has just arrived. They're still only available in small quantities so please contact us soon if you are interested. The 127ED sells for 1299 pounds which is excellent value for an ED triplet of this quality.

New ExtraFlat Eyepieces from Optical Vision

Most eyepieces have focal planes that are slightly curved. The effect is to make the best focus position different for different parts of the focal plane. Optical Vision's new range of eyepieces tries to overcome this problem by producing a much flatter focal plane. And it does it at a very affordable price.

We haven't had chance to carry out any extensive testing but the eyepieces look and feel good. Lee is going to test them as the opportunity arises and we'll let you know how we get on. In the meantime, you can find them on our web site on this page . If you fancy trying them yourself please let us know what you think to them.

Big Bang? or Let There be Light?

Next week physicists at CERN will turn on the world's largest scientific experiment in an attempt to find the Higgs Boson and a host of other exotic particles. They plan to recreate conditions that prevailed billions of years ago in the first millionth of a second after the Big Bang. A monster of a machine built in a 27km circular tunnel, using enormous magnetic fields produced by super-conducting magnets will be used to search for the smallest of particles.

Meanwhile, across the pond, one of the candidates to become Vice-President of the most powerful nation on Earth appears to believe that the world (and presumably the Universe) was created eight thousand years ago.

One of the possible (but unlikely) effects of the CERN experiment, according to this morning's radio, will be to convert the Earth into 'strange matter'. I think they're too late; it's a strange old world already.

Looking South at 10 pm from Cambridge, UK

Now that the evenings are darker we can move our observing time back to 10 pm. This means the sky won't appear to have moved as far as it usually does between newsletters, but as the Summer Triangle is due south there is plenty to talk about.

Starting near the horizon, Jupiter is still the brightest object, about 15 degrees to the right of our meridian which runs down the boundary between Sagittarius and Capricorn. Down here near the horizon the Milky Way is also to the right of our meridian and Jupiter is in front of it.

Moving up we find the bright star Altair which marks the bottom of the Summer Triangle. It's in the constellation Aquila, the Eagle and is one of the closest stars to us, being around 17 light-years away. It is about 1.7 times the mass of the Sun so is burning its hydrogen much faster. It is estimated that it is only a few hundred million years old and will complete its time on the main sequence in about a billion years, about ten times faster than the Sun.

Altair is also rotating much faster than the Sun. It completes a revolution in 10.4 hours compared with the Sun's 25.4 days at the equator. This rapid rotation causes it to bulge like Jupiter and it is 14% wider than it is tall.

Just above Aquila lies the third smallest constellation, Sagitta. In mythology it is supposed to be an arrow shot (or loosed as archers prefer to call it) by Hercules. It is an easy shape to recognise even though its main stars are only fourth magnitude.

Sagitta contains one of the most interesting variable stars called FG Sagittae. It is a White Dwarf in the making and has started to shed its outer atmosphere to create a planetary nebula. The interesting thing about it is that these changes can be observed over a timescale of a few decades. Compare this to the typical life cycles of stars which are measured in billions of years and you can appreciate how unlikely it is that we can observe this process taking place.

Unfortunately, FG Sagittae is around 15th magnitude so beyond the reach of most of us. If you would like to learn more about it try this link to the American Association of Variable Star Observers which is featuring it as their 'variable star of the season'.

Just above Sagitta in the constellation of Vulpecula the Fox lies the Dumbbell Nebula, oneof the most photographed objects in the Summer Sky. Looking a little like an hour-glass it is a good object to practice your astro-navigation on, being visible in binoculars and small telescopes. It was the first planetary nebula to be discovered by Charles Messier in 1764 and is number 27 in his famous catalogue.

Above Vulpecula we find ourselves in Cygnus the Swan, flying down the Milky Way. Also known as the Northern Cross this area is rich in deep-sky objects and is good to browse in binoculars. Being almost overhead it is worth getting out a deck chair or similar recliner to avoid getting a stiff neck.

On a clear dark night the Milky Way really stands out and you can see the dark area called the Cygnus Drift or Northern Coalsack. This a a dust cloud obscuring the background stars.

Having told you about one interesting object that you can't see on your meridian, let me frustrate you further by telling you about another. What is thought to be the first black hole ever discovered, Cygnus X-1, is about half a degree from eta Cygni, the bright star about half way down the shaft of the cross. Cygnus X-1 is an x-ray object orbiting a 9th magnitude blue supergiant star.

And Finally...

If you look to the west just after sunset you may be able to see Venus very close to the horizon. It was very bright and easy to see a couple of nights ago. Mars and Mercury are very close to it, making a small group less than five degrees across. These two are much harder to spot but you might like to try with your binoculars. You should be able to get all three planets in one field of view.

Clear Skies and Best Wishes

Neil

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