Member's Obs Log

I hadn’t set out to do any stargazing this evening; in fact astronomy was completely out of my head at the start. I was on a sailing yacht leaving North Shields with a group of other young people and as we were going through the lock to leave a brilliant light flashed up in the sky, did a graceful arc and then fizzled out. At first I just passed it off as a firework, as it looked the same as one that has just been set off and not exploded yet but it stayed there for a good 10 seconds, therefore proving itself as something different. It was a definite sense of déjà vu as a very similar occurrence had happened during an Astrosoc observing session back in April, where we all took the bright orange ball of flame to be first a firework and then a plane on fire before realising that it must have been a fireball.

Shortly after the fireball we left North Shields and headed up the River Tyne and out into the North Sea. Being at sea meant that the light pollution was very low and the clear skies gave a great night’s naked eye stargazing. The main sights were Jupiter and Venus although we did spend a fair while looking at constellations such as Ursa Major and Orion and then star hopping to Polaris and Sirius. The Pleiades was also viewable later on and the position of the Andromeda Galaxy found, but due to the lack of binoculars we couldn’t actually look at it. The final sight of the night (around 2am) was the Milky Way which for many was the first time they’d seen it and due to the cold, crisp condition of the atmosphere it looked even more spectacular than normal, a brilliant way to end a very good impromptu night of astronomy.

Rachael Sharp

Member's Obs Log

After a truly miserable string of weather to start off the summer, I took the first clear opportunity to reacquaint myself with my Skywatcher 114 telescope and do some astro-imaging using the society’s Canon EOS 350D DSLR Camera. There are few places in the UK with darker skies than Dartmoor National Park and since I live only a 30 minute drive away, this was the perfect place to go for a serious night of astronomy. After picking a site I grabbed my gear and tent before heading up for the night; unfortunately observing through until dawn would leave me in no fit state to drive home! The rocky outcrop of the appropriately named Top Tor offered superbly clear horizons, and although cloud banks were visible low in each direction, they steered well clear and it remained beautifully clear; despite the current light summer nights this was undoubtedly the best sky I have seen in my life!

Being set up in time for sunset meant I had a couple of hours to amuse myself before it got properly dark, though both Saturn and the waxing crescent moon close to the western horizon provided perfect early targets before they sank out of view. As the red light of sunset faded the beautiful summer Milky Way began to emerge, and by 11pm had reached its full glory; to the naked eye the dust lanes were easily visible along its length and the sprawling star field provided such a wealth of detail that I spent much of the night just lying back and taking it all in! Being at higher altitude with low horizons meant that more of the galactic central region was visible than is typical in the UK; the entire constellations of Sagittarius and Scorpius were visible and some relatively short exposures mounted on my equatorial tripod revealed exquisite detail that is just not visible with any sort of light pollution.

While my telescope has served me very well over the last 5 years for naked eye observing, it is only a beginner’s scope and sadly not up to much in the way of astrophotography. While it did manage to image the moon and Saturn to reasonable quality, my attempts to capture the Lagoon nebula (M8) and the Andromeda galaxy (M31) mostly resulted in star trails due to the poor tracking quality of my little stepper motor, and on clean shots the telescope’s poor coma resulted in off-axis smearing of stars. In short, I think it may be time to upgrade to a better model if I can afford it! The dark skies more than made up for this shortcoming however, as the same targets appeared beautifully at low magnification, and I went on to image the Double Cluster (NGC884) between Perseus and Cassiopeia before attempting some star trails to the North. Around 2:30am the camera battery died and I took this as a sign to pack up for the night, though with two more hours of darkness it was extremely difficult to tear myself away!

The full set of images from the night can be found on my Flickr page (http://www.flickr.com/photos/mwilby/), dedicated to astrophotogrpahy. If you live near a dark sky region, I would seriously advise you to head up there for a night just to see the wonders of the Milky Way; you don’t need to lug a telescope there to appreciate it! Also, if any society member does any observing outside AstroSoc’s events, please send us an Obs Log ( This e-mail address is being protected from spambots. You need JavaScript enabled to view it ) and we will put it up on the website!

Mike Wilby

Astrophotographer 2012/13

December - Geminids: The Celestial Fairy Lights

The winter skies are some of the most favourable for astronomy, both in terms of available targets and time in which to observe them (though the weather means that even the keenest amateur astronomer daren’t venture out for more than a few hours at a time!). With the Winter Solstice on the 22nd, there is over twelve hours of true astronomical darkness (where the sun is over 12˚ below the horizon; this is approximately 3 hours shorter than the time described by civil twilight).

For those willing to brave the cold there is plenty of planetary astronomy to be done; Venus is prominent at dusk, shining at magnitude -3.8 low on the South-Western horizon. At a separation of 31˚ from the sun, you have over an hour after sunset (currently about 4pm) to view the planet; its disk shows no surface features due to the thick atmosphere, but it’s brilliance and display of phases at least makes it worth a look. Mars has begun to make its presence felt in the late evening skies, rising at 10:30pm by the end of the month; it still has a while to go before it reaches opposition next March and as such the disk is small and needs a decent telescope to resolve. The moon is full on the 10th, waning to new on the 25th, while Jupiter is (as ever) very prominent in the sky, with its dynamic surface and moons always worth a look.

There are two meteor showers of note this month, the first of these being the Geminids, which peak on the 13th and 14th of December. The radiant is located just to the North of Castor, one of the two brightest stars in the constellation of Gemini. With typically bright white, slow moving meteors and a ZHR* of 60-70 this shower is often one of the most spectacular of the year, though this time the presence of a near-full moon in neighbouring Cancer will severely hamper viewing. The parent body 3200 Phaethon is not a comet, but a 5km asteroid which is thought to have undergone a major orbit-altering collision in astronomically recent times; small increases in activity have been noted in this shower over numerous years which imply continuing redistribution of the debris trail. The second shower this month is the somewhat smaller Ursids, peaking between the 17th and 25th of December with a radiant near the main body of Ursa Minor. These do have the advantage of dark moonless skies, but the expected ZHR of 10-15 means they are still unlikely to be as impressive as the Geminids which precede them.

For all showers, the best technique for observing is to lie back in a space with a relatively clear horizon, but which puts any direct sources of light (including the moon) out of your field of vision; then just sit back, relax and watch the show!

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*Zenithal Hourly Rate; the average number of meteors visible per hour to an observer with a clear horizon - in practice you would have to be very lucky to see this many!

This is the November Astrosoc bulletin. Written by Michael Wilby

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Now that the clocks have gone back, the long (and of course cold) nights of deep astronomical darkness are setting in; personally I find the winter sky to be one of the most spectacular, as it contains a wealth of objects of all types and many easily identifiable constellations.

The moon is full this month on the 10th when it passes close by Jupiter; it then proceeds to wane to new on the 25th. While the gas giant has passed its opposition on the 29th, Jupiter is still going to be very prominent in the evening sky for the next few months and is, as ever, an excellent target.

One of the most iconic and easily identifiable constellations is sidling into the evening sky this month; Orion is currently rising at approximately 9pm, but by the end of the month will be fully visible by 8pm. It contains one of the most active star forming regions in our Sun’s neighbourhood, vast clouds of gas which lie in the line of our spiral arm; the most famous of these is the Orion Nebula (M42) which is easily identifiable even without any optical aid. With a telescope it is possible to discern more of the nebula’s extent, as well as the central trapezium of young stars which are currently blowing off their surrounding gas cocoon. Other notable nebulae in the constellation include the Running Man Nebula, Horsehead and Flame nebulae while all lie above M42 towards the belt of Orion (see the attached photo, which was taken by a friend from his back garden using amateur equipment).

Orion also contains two stars at the other end of their lives; the blue supergiant Rigel is found in the lower right of the ‘hourglass’ shape of the constellation, but the real show is Betelgeuse, the brightest star in the constellation at magnitude +0.45. At 20 times the mass of the sun it is in its Red supergiant phase, and is likely to be the next star in our galaxy to explode as a supernova!

There are numerous small meteor showers occurring this month; the first of which is the Taurids on the 5th, with the Northern Taurids and Leonids following on the 12th and 15th respectively. These all have expected ZHR of around 15 (Zenithal Hourly Rates - the expected number of meteors visible to an observer with a clear horizon). These are all due to different comet trails across Earth’s orbit, and are a warm-up to the real star of the winter meteor showers; the Geminids next month.