Look Up! October 2008
HantsAstro.org
ISSN 1758-2210
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Buyers Guide Part I news | reviews | views | what’s on | out there
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Butser Ancient Farm under a dark sky... Butser Ancient Farm is naturally shielded from the worst of the light pollution from three sides. It is ideal for deep sky observing and imaging and getting the best out of your telescope. Skies have been recorded here down (so far!) to Magnitude 20.7 per ArcSecond, and are as good as the West Country or the Norfolk Coast. For only £4 per session you can experience dark skies in a tranquil and safe setting. If it’s cold, a warm and welcoming fire awaits you in the ancient roundhouse.
Just off the A3, south of Butser Hill, and 10 miles north of Portsmouth it has easy access from all points of the compass, and is an hour and a half from London, and twenty minutes from the South Coast.
For further info and to book yourself a Pass, please contact HantsAstro on 023 9261 7092 or by e-mail: subscribe@hantsastro.org TM
Cover: Meade ETX90 - Picture by Graham Green for review photoshoot with a Canon EOS 350 DLSR. Telescope supplied by Neil Phillipson of Astronomia of Dorking.
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contents Look Up! October 2008 edition 06 News HantsAstro - September was aflame!
Hampshire is our Playground
Page 4
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Report - Chariot of Fire?
HantsAstro Exclusive! Fireball seen across Europe. First Analysis. We bagged the only image..!
Picture
First Type
Page 6
Page 9
Richie Jarvis - a 6” Newtonian? Impressive...
Review
Page 10
Review
Page 11
Buyers Guide Part I
Page 12-16
Yes, we called it Herstmonsoon... and loved it!
Baader Hyperion ClickStop 8-24mm Zoom Eyepiece
Small ‘scopes and binoculars. SkyMax 102T Review
Out There
Page 19
Look Up in October
Page 20
Astronomy in Hampshire for October
What’s in the Sky tonight for this month TM
Contacts and Details David Woods - Editor & Publisher Look Up! eZine Editorial David Woods - david.woods@hantsastro.org Web Site: - www.hantsastro.org Tel: 023 9261 7092 Fax: 023 9257 0283 Skype: iodesign Post: HantsAstro.org 11 Drift Road, Clanfield, Hants PO8 0JJ Look Up! Electronic Magazine is published 1st of the month ISSN 1758-2210 This eZine is published on behalf of the HantsAstro.orgTM. Any opinions and views expressed in this publication are not necessarily those of the Editor, Publisher, Sponsors or Advertisers of HantsAstro,org. HantsAstroTM is a society member of the Federation of Astronomical Societies (www.fedastro.org.uk). Where Links take you to other sites, the Editor, Publisher and Webmaster cannot be held responsible for the content of those sites. HantsAstro.orgTM and Look Up! eZine and related devices are protected by registered copyright ©2008 All Rights Reserved. HantsAstroTM a trading name of I.O Design Limited. No reproduction of any material is permitted without express permission of the owners.
What a month that was! Herstmonceux was a real boon for the group with nearly twenty members joining during the festival and the week after. Our first observing sessions were a real eyeopener and we now have a fleet of eight telescopes with every size and type of aperture catered for. All we need is you. The launch of our ClearSkies page with accurate weather reporting from astroforecast.org, is becoming something we can really trust as an observing group. As accurate weather reports are a pre-requiste if you do what we do. We’re also attending The National Space Week event on the 4th Oct at INTECH, Winchester and then 22nd Oct is the long awaited Telescope Amnesty, starting at 6pm. We kick off the event as co-hosts with a free drop-in advice session, with our own Core Team members and our fleet of telescopes. Then at 8pm a fantastic Planetarium Show with Ninian Boyle and Pete Lawrence of BBC Sky@Night fame will show you what you can do with your telescope. Our observing sessions are becoming something a bit special too, see pages 4-7. Is it the shape of things to come?
David Woods: Founder HantsAstro.org
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NEWS
HantsAstro in October
September was aflame!
Before we start with October let’s look back at the past
month. We kicked off the month with the group attending the Herstmonceux Astronomy Festival on the 6th September, which we are reporting on in Page 10. For HantsAstro it was a resounding success, as we have now had a big leap in membership and are rapidly heading towards 90 members which is our biggest growth since we started! Nearly 50% in one month. We made quite a number of new friends that week-end. Our exhibition stand attracted a lot of attention and was very striking. We wanted to make an impact and I think that we did just that. The next couple weeks were spent sorting out the new Membership applications. Sorry again to those that had to wait for a reply regarding their application, it caught us by surprise. We have cleared most of the back log now and are getting the magazine together for the next few issues. A lot of work has been done on our new buyer’s guide series which will be running for the next three months in the magazine. In January and February there will be two extra supplements for
Observing at INTECH - 25th Sept 2008
DSLR cameras and astrophotography, not forgetting the higher end CCD cameras that are now breaking onto the scene in ever-increasing numbers. 19th Sept - Butser Ancient Farm Graham disappeared and took loads of photographs during the evening of both the site and the observers that attended, as well as all the lovely kit that turned up. Bizarrely, one of the things the group is trying to prove is that you don’t need fancy equipment to enjoy astronomy, however, most of the telescopes that arrived were real astro-imagers delight. We had our own 10 inch dobsonian, my LXD75 and the baby Megrez 72FD, but these were overshadowed by Ady’s brand spanking new LX200 ACF. It kind of stole the show and it well deserved to, as the views it served up were utterly stunning. Tackling difficult targets like Neptune and the elusive Uranus proved a piece of cake from his top-of-the-line telescope. The only downside of it was it’s incredible weight, it is more of a transportable instrument and a portable one. Everyone who attended really enjoyed themselves, which at the end of the day (or night!) is what we are all about. This night proved many things, firstly that even with a little cloud some great observing can take place, and that dew can be a real problem. Importantly it proved that weather forecasting
is accurate to the hour on the night itself. This accuracy was proven again at INTECH. 26th Sept – INTECH, Winchester. This was one of those nights when it could have gone either way, but by trusting my instincts and the weather forecasts that we claim on the website, we were not wrong. In the next few pages you can read all about the fireball event so I will not go on about it here. Disappointingly the lights didn’t go off from the building until 9:30 p.m. They were still not fully out on the outside of the building, this is something we are seeking to resolve with the management team and are working towards a solution. We know they will do everything they can, as they are starting to see the benefits of having group like HantsAstro there... Even with the lights on, we were still able to record magnitude 20 arc second dark skies, which just goes to illustrate the potential of this site. What we did discover, is that the Holiday Inn are constructing a new hotel at the entrance to the site which will boast 120 rooms. No doubt it will also boast parking for 120 cars, and of course all the insecurity lighting that goes with it.That’s twelve months away. It almost goes without saying we will be having a little chat with them to see how much this may affect future
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NEWS
Observing at BUTSER - 19th Sept 2008
observing at this site. If we can assist them in reducing light pollution for their financial benefit as well as that of the environment, then everyone wins. Something tells me though, the rules and regulations don’t allow for any kind of leeway when looking at the night sky. With ever-increasing energy costs I’m sure that any business will want to revisit the way that they illuminate their place of business, while maintaining the perceived safety and security of the public. Watch this space, because if any group can make a positive change or rise to a challenge, we can. I can only hope that we are able to seek some resolution to the insidious nature of light pollution that now threatens the future use of this site. It’s one of our advantages that we are able to migrate from site to site if required and we are lucky that as a group we are quite portable. There are some astronomical societies out there with large observatory complexes that are blighted with increasing light pollution over them and this is a real issue. For us it’s a real disappointment, but hopefully it’s a resolvable one. On two occasions when we have been there before for evaluation with Core Team members, we are always amazed to see the ISS greeting us, and on this night a spectacular event unfolded before our eyes. In spite of these potential problems it was probably one of the most memorable nights of observing that anyone could possibly recall. The Andromeda galaxy was easily seen in the 4, 5 and 6 inch telescopes and was a great comparison. Jupiter was an easy target although a little low in the sky. But it was the event at Five to Ten that really, really rocked our world. As I said, every time we are here something special happens. Let’s see what October brings, maybe a chance
to turn down the light? Buyer’s Guide When Christmas comes it’s never a good idea to be a turkey, or in fact to buy one especially if it’s in the form of a telescope. That said, many telescopes are not that bad nowadays, however, it really is the subtle nuances of engineering and build quality that separate the men from the boys when it comes to constructing a decent optical instrument. Like any investment, of either time or money or both, it’s a good idea to get an overview. For those new to astronomy I hope it helps you make the right choice, and those who are the real die-hards amongst you, that you find some useful info as well. The real challenge is where we translate this buyers’ guide to the website which is something that we will be looking to do over the Christmas period. It should prove unique and very relevant for the UK astronomy scene. We had quite a response from last month’s request for a new strapline for the group and several new examples have come to light, these will be posted on the website in due course. The competition is still open and a shiny unopened box containing Red Shift Six awaits the winning strapline. We will close the competition on the first of December and make an announcement via e-mail to the group. Out there
Due to many requests, and some serious box ticking on the application forms, we are arranging a series of ‘ away missions’. Some of these will include day trips, and some of them will actually be observing sessions outside of Hampshire. I would welcome any requests or ideas so that we can put this out to the membership and see how it flies. The most obvious first trip should be Greenwich in London. Hands up who wants to go to that? Let me know and I will get some numbers and costs together. Weather forecasting is now quite accurate regarding these sessions and we will only cancel if the cloud cover is greater than 50%, or if there is a predicted severe dew problem or just plain damp. The more we use these sites then the more we can improve our service to our members, and it also gives us a bit more of a voice. We work with the site owners to provide a safe and enjoyable environment, and a lot of work is done outside of the group to ensure that this happens. The least we can do is turn up, so please do, you’ll have a great night out for sure. I look forward to seeing you all soon.
David Woods HantsAstro.org
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Chariot of Fire!
Fireball Sighting seen across UK & Europe
Photo: Graham Green Processing & Mapping: Martin Saban-Smith Editorial/Research: David Woods
They say sometimes the best things in life are free. In this
instance no one could argue that fact. On the 25th of September, our first real observing session at the INTECH Science Centre and Planetarium, our observing group was witness to a rarely seen event in the sky. Travelling slowly from west to east until it disappeared over the horizon, a fireball was seen tearing across the sky and leaving behind it a trail which at first sight looks like the contrail from a jet engine, but this was no ordinary flight. For several seconds all those present were rooted to the
spot, silent, waiting, observing. Trying to absorb and understand what we were seeing, then suddenly someone turned round and said quick take a picture! Graham was tending to his camera, he looked over his shoulder and saw the fireball, and at first it didn’t register. Then he quickly swung round and the shot you see above you is the result. It is, as far as we know, the only image of this event. This fireball was seen and reported to us from as far north as Manchester, along the South Coast and across to France. Luckily the skies were clear long enough for us to see this
magnificent yet dramatic destruction of an object in our atmosphere. The question remains, what is it and where did it come from? Over the next few days and after much research, many more reports came to light across the web and via e-mail to us, as we posted the picture on the front page of our website and on several forums online. A picture was beginning to build. It appears that there is some real science that exists in this picture and further analysis and enhancements reveal more of the story.
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Chariot of Fire!
Could it be a defunct satellite that was knocked out of orbit or some other man-made object? Could it be some remnant of the Comet 2P/Enkle, or something more worrying, like a rogue chunk of ice and rock? If you look at the enhancement of the fireball itself, it appears that this object was tumbling and rotating at speed as it fell through sky and was not travelling in a straight line. It was actually being slowed by the atmosphere as you can clearly see the curve in its trajectory. It is also a clean burn, which when analysed is unlikely to be a small body of
ice and rock as this would break up into smaller pieces. If it is something from outside our orbit, then hopefully this image should help produce a code of probability regarding its origin. If there are any other images that match what we have, then we would be interested to see those too. Now we have dissected this image, we have published it in full and would welcome any input in finding the answer to the source of this object and it’s demise. If anyone in the UK or abroad has seen this object, then please write in to us, as we will compile all the rel-
evant data and send it to Spaceguard UK as well as other interested parties. After calling them, we discovered that many objects like this are never reported or even seen, which indeed makes this a rare event and we were lucky to be able to witness it. Hopefully by next month we shall have a much clearer picture of what happened that night. If this isn’t a good enough reason to turn up at one of our observing nights, then I don’t know what is! -David Woods
Observing at INTECH - 25th Sept 2008
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Telescope Amnesty! 22 Oct 2008 FREE advice session, followed by Planetarium Show. With the HantsAstro online astronomy group, and members of the BBC Sky at Night team. Advice session: 6:00pm - 7:45pm, completely FREE Bring your kit to INTECH for free advice on how to get the best from it. Arrive any time after 6:00pm for this drop-in event. Volunteers from local astronomy societies and universities will join members of the BBC Sky at Night team to help you use your equipment for an early evening observation on the INTECH terrace. While youre here, try out other equipment, get advice on what to buy (or not to buy!), and find out about local astronomical societies. INTECHs friends the online astronomy group HantsAstro will be helping with this event - ask them about their free observing nights at the INTECH site! No tickets for this event - just drop in anytime from 6:00pm to 7:45pm. Special planetarium show: 8:00pm - 8:45pm ‘A Guide to the Splendours of the Winter Night Sky’ For one night only; a show by Pete Lawrence and Ninian Boyle from the BBC Sky at Night team. Join our two expert astronomers as they take you on a trip across the winter night sky, showing you some wondrous sights that will delight and astound. There’s something for everyone here, from craters on the Moon to distant galaxies. Come along, enjoy the show and prepare to be inspired.
INTECH Planetarium Telegraph Way, Morn Hill, Winchester, SO21 1HZ
Bookings: Tel: 01962 86379 Email:htct@intech-uk.com
Price: £6 adults / £5 concessions Age restriction: 8+ only.
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NGC7635 - Bubble Nebula - Richie Jarvis
Location: South Chailey, East Sussex Equipment: GSO GS-150 Newt’ SXV-H9 CCD
The image itself is only 1392 x 1040 pixels, as its taken with a small format CCD (the SXV-H9). The Ha filter is a 13nm Astronomiks filter I picked up second hand recently for £60.
Imaging Gear Small is beautiful
Processing wise, quite simple really - The Luminance exposure were binned 1x1 (full size - 1392 x 1040), the HaGB frames were binned 2x2 (half-size frames - gives a x4 boost at the cost of lesser resolution. I stacked each ‘colour’, and ran DDP against them in MaximDL. To tighten the stars, I saved the Luminance layer in SBIG format, and performed a Lucy-Richardson deconvolve in the freeware CCDsharp from SBIG. To avoid a bug in MaximDL, I doubled the size of the HaGB layers to be 1392 x 1040.
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Review Herstmonceux Astronomy Fair
The clouds cleared and again we were the only ones who saw the stars
‘Herstmonsoon’ 2008 With that title you would imagine that the weekend was a total washout, but no. Despite the torrential downfalls of Friday and Saturday night, the rain clouds parted in the early hours of Saturday revealing a star studded spectacle. This was dominated by the rising of the Pleiades, with pyrotechnics kindly provided by the Piscids meteor shower. Our friend Matt spotted several in less than an hour! (The Piscids hit maximum on the ninth with an expected ZHR of 5). With an unexpected dark sky and Dave behind the focuser of his Megrez 72, I naturally grabbed my camera and in the style of David Bellamy, gaited through the swampy grounds of the former RGO.
Sunday on the other hand was not to be as spectacular (outside the beer tent!). Although the rain had stopped at around midnight, the cloud persisted. The only option left was to continue with the consumption of the Astro-beer/ wine back at the ‘observation tents’ with a little light acoustic accompaniment (apologies to all the angry and sometimes quite aggressive Astro-sleepers – sorry guys) and many thanx to ‘Rocket-man’ for his bard style jokes… Graham Green
We meet the ultimate astronomer Sir Patrick Moore...
As the CMOS sensor within my camera set busy in collecting the nocturnal photons, I could not help but chuckle at the amount of tents with the rumblings of stertorous astronomers. Never the less on went the imaging, the results of which I hope you will agree, are quite stunning.
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Review
Baader Planetarium Hyperion ClickStop Zoom 8-24mm £147 Zoom Eyepieces are normally
viewed with a tinge of suspicion. The more lenses and mirrors the place between you and your object, then usually the worst it will look. Like ours when you’re out on the field carrying lots of eyepieces can be literally a real handful. Baader planetarium offer a solution with their new Hyperion eyepiece range. Firstly it’s useful, because you can adapt it to fit either 2 inch or 1 ¼ inch eyepieces. Secondly, you can attach a T-adapter so you can fit your camera to it. And in this case it
offers four magnifications from 24 mm down to 8mm, and is parfocal, which means it stays in focus. As an all in one upgrade it comes fully recommended. A 5 in 1 eyepiece, 8, 12, 16, 20 & 24mm with a wide field of 68° at 8mm. Sorted! Downside, it’s a bit heavy as you’d expect, but being chunky it’s hard to lose. The ‘Phantom coatings’ do an excellent job of making your image clear bright and contrasty. I was so impressed I bought one myself. It may well be the price of a small telescope, but this
versatility and quality make this an ideal upgrade for a small refractor or Dobsonian and the astronomer on the move. I used it on both, and its convenience was apparent. As optics improve, we will no doubt see more accessories like this. This is a wise investment. - DW
Thanks to Astronomia for suppling this eyepiece and making me poorer wracked with guilt but elated. If you wish to feel a simalar way, give Neil or Matt a call at Astronomia on 01306 640714. Or visit their website: www.astronomia.co.uk
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Buyers Guide Part I
Meade ETX90 GOTO Telescope
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HantsAstro Buyer Guide - Part 1
Now, we’re not trying to replace any books from
eminent experts of which there are many, but buyers’ guides fall distinctly into two categories: factual and technical or factual and personal. This I guess, must be the latter, as the technical stuff isn’t really needed until such time as you really get into astronomy. What we are trying to prove as a group, is that you don’t need to buy expensive kit in order to get a good view or to learn the sky. Buying a telescope is a bit like buying a camera, the most expensive one you can buy doesn’t automatically make you a great photographer, merely a better equipped one. Ironically some of my best photographs were taken when I was just starting out in photography, with the most basic of equipment. Astronomy is a little different because at the end of the day what you are seeing is an infinite view, and it’s the quality of equipment that defines what you see, as well as your location and seeing conditions.
Manufacturers of telescopes have some basic rules and once you understand the architecture that makes a good telescope, then it’s quite easy to identify one. But without reinventing the wheel or going over stuff you can find on the web, we are going to hang our hat on some typical examples of good scopes that are affordable. In fact, if you turn up to one of our observing sessions you’ll find that we use the ‘scopes a regular basis. Our list follows thus: Aperture 70 mm Vixen Refractor 102 mm SkyWatcher SkyMax102 130 mm SkyWatcher 130M 150 mm SkyWatcher 150P 150mm Optrons 150-1400 200 mm Meade LX10 250 mm Revelation 10
Ratio f/12 .9 f1/2.74 f/6.92 f/5 f/9.3 f/10 f/5
Focal Length 900 mm 1300 mm 900 mm 750 mm 1400 mm 2000 mm 1250mm
What I have deliberately left out now is the type of telescope. Basically it comes down to three things that you can see from the above table. This dictates the amount of light you can gather, and the focal ratio is dictated by the length of the light path of a particular scope. I’ll let you into a little secret, physically telescopes are rarely made over 1 metre in length, otherwise it would be too big and too heavy! Example. A 12 inch Newtonian scope which is F5 in length, is five times longer than the diameter of it’s aperture. So, that would mean the tube length would be a whopping 60 inches or 5 foot long in old money. Try getting that on the back seat of your car! During the 70s and 80s something called aperture fever took hold, because basically the more light you can gather, then the better the view. For the most part that’s true, which is why some of the largest optical telescopes in the world have giant mirrors that catch the light
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from the furthest edges of space. But you and me want to look at the stars, and do it cheaply. So manufacturers, for reasons of production costs more than anything else, keep their scopes to a manageable size. Now - before the techie guys throw their hands up in horror, I’m talking about telescopes that cost less than £1500. You can get specialist big stuff but that’s not what we’re discussing here. If the second column was headed with the type of telescope, then that would define the manner in which the light is gathered. A Refractor is by far the simplest set up along with the Newtonian reflector, which simply is nothing more than a tube and two mirrors in critical alignment. Refractor’s use lenses instead of mirrors. Over the years prices have come down and build quality has improved, but the early market was flooded with cheap and sometimes quite horrible telescopes which did a lot to put the astronomer off from pursuing his or her hobby. Unless you go for the really cheap end of the market it’s now difficult to buy a really bad telescope. But here we are dealing with photons of light that have travelled many thousands of light years, and that’s lots of zeros in terms of miles. So when it reaches your eye you want to make sure you can get the best possible image for your budget. It’s the pursuit of this which makes astronomy an interesting subject, purely on a technical level.
So why the difference? In 2009 we celebrate 400 years of the telescope So it’s quite an old technology which has been refined over the centuries and there have been many variations on a theme, and the table illustrated pretty much defines that. Latest designs have folded up the light path so it is possible to emulate some of the longest focal lengths, which are ideal for looking at stars and planets and working at high magnifications. Recently, due to better mirrors and optics, faster and faster telescopes in
terms of focal ratio, have come to the fore. These are particularly suitable for finding deep sky objects, and they work just like your camera lens. A pin hole camera will take a sharp picture only in bright light, if you want to do the same thing when it’s darker, that hole needs to be bigger, but then it can get out of focus. That’s where good optics come in. Astrophotography relies heavily on fast telescopes to capture the nebulous clouds of stars, and those wondrous Hubble like pictures you see in our magazine and others.
Refractor 150mm f8 Considered a big telescope. It is at 4 foot long!
Depending on what kind of astronomy you wish to do, will define what sort of scope you may first buy. That’s the point of this guide, to show you the difference between the telescopes and what they can do, so you can head off in a particular direction. In the main, if you’re new to astronomy you might require an instrument that is a good all rounder, and these readily exist. As you get more into this astronomy lark, you may discover, like the rest of us, one telescope is not enough! So, in the later part of this guide we will go on discuss the finer points if you’re looking to upgrade. Over the past five or six years the edges have blurred between the different types of telescopes, which means choosing the right one is harder. In fact, the vast majority of them are quite good.
Schmidt-Newtonian 200mm f5 (standard Newt’s are open and use spider vanes instead of glass. Glass variant eliminates those diffraction spikes for nicer looking images...)
Eventually we will be looking to put this information we are compiling online and hopefully will have produced a definitive list of telescopes that currently available in the United Kingdom. The long-term goal of this is to then create reviews from as many types of experiences as possible, and that’s where you all come in. All your comments and feedback are very welcome, as we all shape astronomy in our own way by what we buy and how we use it. Therefore,in this part we’ll start off with my experience, with the SkyWatcher SkyMax 102T. So let’s get started!
Schmidt-Cassegrain 200mm f10 (stubby tube folds up the light path unless you like 6ft long telescopes!)
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REVIEW
The SkyMax 102T OTA
Words: David Woods
SkyWatcher Maksutov Telescope Range £129 - £399 80, 90, 102, 127 Overview This type of telescope is a prime example of how the market has changed over recent years. It takes a modern design, namely a Maksutov-Cassegrain, and using modern production techniques turns it into something quite affordable. This type of telescope is a simple design and therefore quite cheap to produce and, after my very bad experience with a cheap Newtonian reflector, this was quite a revelation! Size matters 80 mm aperture is not much for a large pair of binoculars but the advantage with a small telescope is that you can change magnification. This was discussed in the first edition of Look Up! magazine and, starting at £129 including the mount, it’s a great way of getting into astronomy. However, this design of telescope, uses quite a thick mirror which takes a long time to cool down, especially at large apertures. So if you want to use this type, it’s best to stick it outside to let it cool down, that way you can get the best out of any telescope and this is no different. The 127 mm can take over an hour to cool down, and compared to the smallest version, pulls in a massive amount of light. 55% more that the 102mm version... I picked the 102 mm version as it was smaller, a bit quicker to cool down and a bit lighter, so that meant it was the ultimate grab and go telescope.
Because of its design it folds the light path up at about the 1300 mm focal length range, which makes them ideal for gazing at stars and planets. The size of each model improves it’s light gathering power. The 127 version is not too bad with galaxies and some nebulous either, however, it’s still running at about f/12. I have to admit I still hanker after the 127 version but am still glad of my purchase. These can either be bought with a German Equatorial Mount or, as an optical tube assembly (OTA) if you want to mount them on a simpler photographic tripod. However, in the case of the 127, make sure it’s a beefy tripod like a video version, as it’s steadier and can handle the extra weight. What’s it like? Very good overall, the much acclaimed 127 and its smaller brother’s are ideal starter Scopes if you want something smaller than a refractor or Newtonian reflector. The supplied red dot finder is easy to use and great for taking aim. All starter telescopes should be supplied with them ideally, as most 6x30mm finderscopes supplied with entry-level telescopes aren’t really a great deal of use. It’s one of the reasons why most people recommend 50 mm binoculars as the minimum for stargazing, as anything smaller just doesn’t capture enough light! Apart
from the cooling down time which is overcome easily by planning ahead, the downside is that it has a large central obstruction from the secondary mirror, which is the other side of that silver bit in the middle of the front lens. The primary mirror at the back is a bit like a fat, thick Polo Mint, which is where the light travels through to the diagonal prism and your eyepiece. It has less contrast than a Newtonian reflector as a result, so the star field does not appear as dark as it would on a decent sized reflector. A refractor does not have this problem as there is no obstruction to block out the light. The optics produce a clear and sharp image, which is a testament to the build quality. The latest version uses something called a SupaTrak Mount. This is very similar to the Celestron Nexstar and some of the small Meade GOTO refractor telescopes, in that it uses a dual axis drive system to track your objects. This is a big step up from a standard manual mount. Being Alt-azimuth, lining it up with the polestar is not as critical, as it is with a German Equatorial Mount in order to keep the object in the eye piece and tracking properly. For our observing sessions this is one of the quickest telescopes, next to our Dobsonsian, to set up. As an alternative to a long wheelbase refractor and for its price its a good buy.
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...this is what it’s all about
Getting started If you search the Web you’ll find most recommendations will be that you start off with a star map and a good pair of binoculars. Yes, that’s very true, but what pair of binoculars should you get? If you are starting out, then a cheap pair will suffice. A pair of 50mm binoculars not beyond 12 times magnification is a very good choice. Anything bigger will be too heavy for you to hold for any period of time. Anything much smaller, say less than 30 mm, won’t really gather enough light to be that useful. There are also image stabilising binoculars which are available priced from couple of hundred pounds. These offer a surprisingly good alternative, but they do come at a price. Most people start off with a 5 or 6 inch diameter reflecting telescope on a cheap Equatorial Mount. The SkyMax review illustrates that there is an alternative. Next month we’ll be looking at refractors at both the low end and high end of what is available and what the differences are between them. The third instalment will be reflectors and the larger apertures, plus we will be touching on some of the more specialist stuff later on.
The telescopes we have at our observing sessions reflect what is currently available on the market and are available for you to use if you join us on a session. This will get you out there and let you try the different types of telescope, to discover which one is best for you. It’s not something you will discover simply by reading reviews. One of the most enjoyable aspects of astronomy is getting to learn how to navigate your way around the night sky, and this is far more rewarding than just using a straightforward GOTO telescope, which some may consider cheating. If you are trying to discover an elusive object or home in on a planet that is millions and millions of miles away, then this type of telescope has many advantages and has recently come down in price. The Meade ETX range of telescopes are developed for just that kind of astronomy. They are very similar to the SkyMax, but are computer-controlled and take much of the guess work out of finding your way around the sky. The 80 mm entry-level version of the range is good, but the ETX90 has long held a reputation of being the definitive
starter telescope for many reasons. It offers good light grasp along with computer control and it’s possible to even do some basic astrophotography with it! That’s the point, buying a telescope is indeed an investment and is not something that anyone wants to grow out of. Getting hold of a good allround telescope is wise, as it will allow you to discover different aspects of the night sky and allow you to develop your interest in any area. If you haven’t got one, then a star map of some kind is a must, then just use the optical instruments you were born with, your own eyes. Drive out into the dark countryside, make sure you’re dressed warmly, wait about 20 minutes for your eyes to adapt and see if you can spot the Milky Way traversing over the top of you. You already have a pair of binoculars called eyeballs and they are about 5mm wide. They work well, even with glasses. So, just Look Up!
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Advertisement
solar eclipse On 22nd July 2009 the world will witness the longest total solar eclipse in over a century - the likes
of which will not be seen again for another 100 years. Many Eclipse enthusiasts are planning to go to China to view the event and several China tours that include the Eclipse have recently appeared on the market. The most characteristic feature of your eclipse tour is viewing the eclipse in a private site, how did you manage to do that? Chartering private sites is not easy in China and we have made use of our extensive local networks to achieve this. After short-listing several locations along the Central-line between Shanghai and Hangzhou, finding our own site was an intricate process. In selecting the most suitable location, we worked with the Beijing’s Central Astronomy Department and drew from NASA research. Although the Umbral Shadow covers a vast area, many places are either unsuitable due to their proximity to large cities (thus pollution and tall buildings) or belong to the government and can not be used. Our site will be exclusive to our guests: Managed flat grassland, with available cover in case of rain and with the added beauty of a pond and traditional pavilion. As it is our own site, it is also possible to arrange refreshments while we wait for the eclipse. There are a few public spaces such as along the coastline, which other tour operators have chosen. We have avoided such locations as we expect tens of thousands of local people to flock them on the eclipse day, thus they will be very crowded.
Why are you featuring the Tidal Bore as well? Tidal Bores are a rare phenomena resulting from the gravitational pull of the sun and moon that are not yet fully explained by science and are found in only a few locations around the world. When deciding on the best viewing location for the Eclipse, our local researchers suggested the Qiantang Tidal Bore as an additional option. Both the Eclipse and the Tidal Bore happen to fall on the 15th day of Chinese lunar calendar, thus we developed the idea of combining the two natural phenonmum into one tour. Are other tour operators offering Eclipse packages? Due to the popularity of this event, other operators, who traditionally specialise either in astrology tours or China have constructed Eclipse packages. Many of them however are taking spectators to the public beaches so have probably not inspected the sites or studied the area. Since we introduced the Tidal Bore as an added feature, other tour operators have done the same. With some however, the location and timing is unsuitable – we have seen at least one operator arrange to take their guests to the Tidal Bore the day before the Eclipse. We know for a fact that the monthly tidal movement will not occur the day before, so they may have some disappointed customers!
off opportunity offer tours that show China in an exciting and vibrant way, along side the stunning natural events. Are you offering just one Eclipse itinerary? No. In addition to the Eclipse and Tidal Bore, which is available as a tour on it’s own, we are now operating several departures which also include the ancient capitals of Beijing and Xian, the Great Wall, UNESCO sites like the Summer Palace andTerracotta Warriors and other the famous locations like the Three Gorges. How is the market reaction? Much better than we expected – we originally planned to operate two tours only but due to demand from people wanting to see more of China as well as the Eclipse, we have extended this to 6. Numbers are limited due to using a private Eclipse location however and places on the tours are filling up quickly. The Total Solar Eclipse viewing takes place in July 2009. Interested Parties can visit Oriental Travel’s dedicated solar eclipse tour website: http://solar-eclipse.orientaltravel.co.uk or call on 0207 6324550 (Greg Stoneham) for a copy of their brochure.
Oriental Travel is a China specialist. What is the company background? In addition to cultural travel and holidays, as a niche tour operator and China specialist for over 8 years, we have worked with many organisations including charities, schools and government departments and have pioneered specialist tour themes such as modern art, geography and traditional gardens. The 2009 Eclipse has provided us with a fantastic one-
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Observing with HantsAstro.
TimeShift Timetable
INTECH
BAF
Site III
September 08
X
25th
X
19th
Not used...
October 08
7/21
9/23
1-5
20-31
1-5
20-31
November 08
4/18
6/20
1-4
20-30
1-4
20-30
December 08
2/16
4/18
1-4
19-31
1-4
19-31
January 09
6/20
8/22
1-4
17-31
1-4
17-31
February 09
3/17
5/19
1-4
16-28
1-4
16-28
March 09
3/17/31
5/19
1-4
17-31
1-4
17-31
April 09
14/28
16/28
1-4
16-30
1-4
16-30
The above table... Our plan is to run up to three sites with fortnightly observing sessions, starting with INTECH and Butser Ancient Farm. Tuesdays/Thursdays are the planned days for INTECH, see the two sets of dates in the first column, which are the first and third weeks of the month. Simple, one night gets called off, then go on to the next slot. (i.e. 7th October is cancelled – we re-arrange for the 9th . If the 21st is cancelled – we re-arrange for the 23rd.) Butser Ancient Farm observing sessions slide either side of the INTECH observing dates, see the two sets of dates in the second column (BAF). They are at the start/ end of the month. The idea is only to meet and observe on clear nights. That’s why we put the dash from 1-4 or 22-30, it could be any day between 1-4 or 22-30. The key dates with this site are to observe when there is little or no moon at Butser or whichever Tuesday/Thursday is best at INTECH. Site III dates are for other sites we have as reserve, including some planned ‘away missions’. HantsAstro might be able to claim we can avoid light pollution, but clouds and bad weather are something else. However, we do have one or two tricks up our sleeve. The timetable is flexible and hopefully you are too. Check our website for regular weather updates on our ClearSkies page: http://www.hanstastro.org/clearskies.html It views 7 days ahead, is 95% accurate within three days and 100% on the night. Why? Because we’ll be there! Join our group and you will be added to updated alerts regarding our observing sessions that are designed to inform you as accurately as possible that the sky is clear, or if staying at home is better... Not only that, because the sites are so close to us we can check right up to the day before, and on the day itself. Sometimes the weather is like a roll of the dice, cloud is not all bad as a good time can be had for some great views. It can be a close call. Our first meeting on the 11th August proved that! It’s new, it’s working but there is still a margin for error. If you’re game, so are we.
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WHAT’S ON Talks & Seminars October 2008 Hampshire Interesting local Astronomy talks take place in the County nearly every month, so please check the relevant website for any updates and contact details. Southampton Astronomical Society October 09 - Titan Speaker - Jerry Workman Edmund Kell Unitarian Church Hall, Bellevue Road Southampton - @ 19:30pm Cost £2 Non-members www.southampton-astronomical-society.org.uk
Hampshire Astronomical Group October 10 - An MOT for Hubble Speaker - Dr John Mason Clanfield Memorial Hall, South Lane, Clanfield PO8 0RB - @ 19:45pm Cost £2 Non-members www.hantsastro.org.uk
Solent Amateur Astronomers Society October 21 - AGM See site for details www.delscope.demon.co.uk/society/home.htm
Basingstoke Astronomical Society October 23 - From Solar System to edge of the Universe Speaker - Dr Robin Catchpole Cliddesden Primary School, Cliddesden, Basingstoke RG25 2QU - @ 19:00pm Cost £2 Non-members www.basingstokeas.org.uk
Vectis Astronomical Society October 24 - Beyond the Eyepiece Speaker - Peter Burgess Newport Parish Church Centre, Newport IOW - @ 19:30pm
Border+ October 2008 Talks & Events across the county line. Please check relevant website for updates and contact details. INTECH Science Centre + Planetarium Winchester, Hants Telescope Amnesty 22 October 6pm £6/5 see site for details! Cost £2 per show in addition to exhibition entry Cost - £6.95 Adults £4.65 under 14’s Check site for schedule www.intech-uk.com Southdowns Planetarium Chichester, West Sussex Various Monthly Shows Check site for details + times and booking Cost - £6 Adults £4 under 16’s www.southdowns.org.uk/sdpt Cody AS Farnborough, Hants www.codyastrosoc.co.uk Farnham AS Farnham, Surrey www.farnham-as.co.uk Guildford AS Guildford, Surrey www.guildfordas.org Newbury AS Newbury, Berkshire www.newburyas.org.uk
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OUT THERE...
Planet+
Our Hampshire Sky - October 2008
October 2008
October Sky
Where the Planets are in our Solar System in October.
Mercury will be visible in the morning sky in the south east towards the middle of the month. The planet reaches a peak between the 22nd and 27th at an altitude of 10 degrees, 40 minutes before sunrise. On the 27th the thin (2%) crescent Moon will look fab close to Mercury. Venus tracks southwards along the horizon in the evening sky and will remain quite low for a while. On the 1st at 18:30 UT the moon sets 5.5 degrees of Venus.
Table Key
The Orionids are associated with Comet Halley and are unfavourable this year thanks to the bright gibbous Moon (!) with a maximum on the 21st; the ZHR is 25 meteors per hour.
RA - Right Ascension Dec - Declination Constell. - Constellation Elongation - Angle between Sun & Planet as seen from Earth Distance - From Earth in Astronomical Units (AU) = 149.598M Km Magnitude - Brightness Diameter - in ArcSeconds Phase - % Visibility of object disc
Full Moon
All Data is based on 15th of the
Jupiter is a good evening object and crosses the meridian mid-month. On the evening of the 7th Jupiter is 6 degrees North West of the first quarter Moon at 19:00 UT. Saturn will become noticeable in the morning sky best seen 31st at 05:00 UT in the constellation of Leo.
Meteors
month from Central Hampshire.
The full ‘Blood Moon’, this name traditionally reflects the final harvest of livestock also referred to as the ‘Hunter’s moon’, a name given to the first full moon after the harvest Moon on the 15th Sept. In the early hours of the 22nd there is an opportunity to see the Moon pass close to the Beehive Cluster (M44) in Cancer, use a small telescope or a pair of binoculars to get the best view.
Next Month. Review of the Meade ETX90 Baader Hyperion EP range StarGPS GOTO upgrade News, Views and more info on our web site. www.hantsastro.org
Clocks Back!
British Summer Time ends at 02:00 BST on 26th October. Clocks “fall back” one hour!
Solar System Data for October 2008 Objects
Sun
Mercury
Venus
Mars
Jupiter
Saturn
The Moon
RA
13h21m22s
12h28m58s
15h31m26s
14h20m05s
19h03m39s
11h14m24s
01h22m32s
Dec
+08°34’26”
-02°29’01”
-19°58’18”
-13°55’09”
-22°58’26”
+06°47’32”
13°07’41”
Virgo
Virgo
Libra
Virgo
Sagittarius
Leo
Pisces
Constell. Elongation
-------
-14.4°
-33.4°
-15.4°
-82.6°
35.2°
-175.4°
0.997 AU
0.780 AU
1.309 AU
2.497 AU
5.174 AU
10.142 AU
0.362 MKm
Magnitude
-26.01
-1.07
-3.85
1.59
-2.07
0.80
-12.73
Diameter
32’04”
08”
12”
03”
38”
16”
32’58”
-------
20%
82%
99%
99%
99%
99%
Distance
Phase
Hampshire is our Playground. Now it’s yours...
If you have any suggestions for improving this star information then please e-mail: david.woods@hantsastro.org
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