Emails – Letters – Tweets – Facebook – Instagram – Kit questions
MESSAGE OF THE MONTH
Deep-sky starter
I enjoy reading the magazine every month as an ongoing gift subscription. Inspired by some of your introductory astrophotography articles I thought it would be interesting to share my first attempt at a deep-sky object, in this case the Orion Nebula, M42 and M43. I’m mainly into observational astronomy, enjoying the fantastic dark skies where I live in the Yorkshire Dales, but I thought it would be fun to see how a non-dedicated astrophotography rig with no tracking would perform. The image here was taken using a StellaLyra 8-inch Dobsonian and an iPhone 12 Pro, mounted over a standard Plössl eyepiece using the Celestron NexYZ phone adaptor. The iPhone camera app worked well, with only minor edits needed to bring out the contrast a little more. It whets the appetite for the slippery slope that is astrophotography!
I’m looking forward to more webinar presentations again this year – they have been great.
A good first deep-sky image effort, Andrew. We hope to see more as you progress down the slippery slope that is imaging! Do stay tuned for details of our next webinars – we’ll have something for you very soon.
This month’s top prize: two Philip’s titles
The ‘Message of the Month’ writer will receive a bundle of two top titles courtesy of astronomy publisher Philip’s: Nigel Henbest’s Stargazing 2022 and Robin Scagell’s Guide to the Northern Constellations
Winner’s details will be passed on to Octopus Publishing to fulfil the prize
Disc of mystery
Thank you for your excellent magazine, I look forward to it every month. Could anyone help in identifying an object that I managed to image (above) in my picture? It crossed the face of the Moon on Friday 14 January at 21:03 and appears as a small black disc. I was trying out a new drive system for my Celestron C102-HD refractor – the drive was a Christmas present from my wife. The image was taken on an iPhone 6 standard camera. My first thought was a weather balloon, but does anyone have any different ideas?
Nigel Williams, Clifford, Hereford
‘Light’ concerns
I really enjoyed the latest edition of The Sky at Night programme, which highlighted the issue of light pollution. It struck a real chord with me as I am sure it did with so many astronomers, professional and amateur, and others who have concerns about artificial lighting. I’m a member of the West Yorkshire Astronomical Society, Pontefract, and I have had a problem light shining into my back garden here in Crofton, near Wakefield, West Yorkshire since March 2020. The offending light is a repurposed streetlight from the 1980s, which is activated by a day/ night sensor and it’s on during all hours of darkness. It is on a neighbouring building owned and operated by Wakefield and District Housing Association, and I have been calling on Wakefield District Council’s Environmental Health Department to take action, so far without any luck. I have had my MP Jon Trickett write on my behalf and have sought advice where I can, emailing the Commission for Dark Skies as well as Citizens Advice, but so far none of my enquiries have resolved the problem.
Steve Kirkman, Crofton, West Yorkshire
Eclipse query
Having received my very first issue of your magazine (the January 2022 issue), I’ve started to go through it page by page. I had a question about something on page 19, in the ‘Looking back’ section. Talking about lunar eclipses, it says here, “In the outer portion of the shadow, known as the penumbra, Earth only partially shadows the Sun.” Could you clarify that, or should it read ‘Moon’ where it says ‘Sun’?
I hope you’ve enjoyed your first issue, Bob! In a lunar eclipse, Earth is the body doing the shadowing: our planet blocks light from the Sun reaching the Moon. So if you were on the Moon at the time, you would see Earth shadowing the Sun. From Earth we see this as the Moon turning red, as the light we see from the Moon has passed through our atmosphere. – Ed.
Constant issue
I have been told that the Hubble constant is not really constant, but changes over time. If this is the case, is our calculated value (whether 68 or 72) the true value of the Hubble constant at this moment in time, or is it from a previous point in time? If the latter is the case, when was it that the value was equal to our calculated value?
Thanks for getting in touch, Ophelia. The Hubble parameter is what changes over time; we call its value in the current Universe the Hubble constant. – Ed
Clarify the view
I have taken some pictures with my phone using my son’s telescope, but I’m not sure what I have captured; I think it looks like a planet. Please could you let me know what you think it is?
Well done for getting the telescope out, Lynnette! What you’ve captured there looks to be a fingerprint on the eyepiece. It’s easy to clean and there’s a handy guide to doing it on our website at https://bit.ly/3IO8LHl . – Ed.
SOCIETY IN FOCUS
Many societies have become used to holding their meetings online since the start of the COVID pandemic and in November last year, the Society for Popular Astronomy (SPA) ran their annual weekend course via Zoom.
The course has been a familiar autumn fixture in the SPA’s calendar since it was first held in 1977. Normally, members are welcomed to the field centre at Preston Montford, Shropshire, for observing and lectures, but in 2020 the event had to be cancelled. In 2021, however, the course was run over one day as a live online session for members.
Organised by SPA vice-president Robin Scagell, the course’s theme was Observing the Planets. Talks were presented by regulars Robin Scagell and Professor Ian Morison, planetary scientist Dr Leigh Fletcher of the University of Leicester and imaging expert Martin Lewis.
Robin says: “Holding the meeting this way meant that many more members could get the feeling of being at the event. We had 77 participants from all over the country and more have now viewed the recordings.
“While it was an event that many members appreciated, we hope that next year we will be back in Shropshire and meeting each other in person once again.”
Non-SPA members can catch up with the lectures, which cover the basics of planetary observing, in a series of videos at tinyurl.com/SPAtalks.
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AstroMike @xRMMike • Jan 17 Tonight’s Wolf Moon (first full Moon of January), captured over Corsley, Wiltshire using a Celestron telescope with a focal length of 1,432mm. #WolfMoon #Lunar #Moon #MoonHour #astronomy @bbcweather @BBCSpringwatch @skyatnightmag
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WE ASKED: How can beginners become better astronomers?
Carol Miller I would suggest patience, online courses and books. Try not to learn too much about the night sky in one go. Having conversations with fellow amateur astronomers is the best way to pick up information. Above all, enjoy yourself!
Raymond Minty A pair of binoculars like 7x50s and Norton’s Star Atlas and Reference Handbook.
Benedict Culm Don’t rush, be patient. It takes time to build up the knowledge, experience and gear. Enjoy the peace and solitude of being under the stars; it’s good for mind and body.
Emma Hugo Get outside and just look at a clear sky. Learn to navigate the constellations and recognise where they are in relation to each other. Get a good pair of binoculars or a small telescope and join a local astronomy club.
Brian Dwyer Spend 15–30 minutes every clear night recognising a few of the brightest stars in your sky. Keep track of their apparent motion during the nights and months ahead.
John Press Don’t just buy a bargain telescope from eBay or Amazon. Instead, speak with your local astronomy club or a dedicated astronomy shop before parting with a penny.
s_swift_2001 • 23 January
For today’s quick data-processing, I’ve worked on an image of the Elephant’s Trunk Nebula I captured from my Bortle 6 Nottingham back garden during some recent clear nights, though the bright Moon didn’t help. It’s a concentration of ionised interstellar gas and dust in Cepheus, about 2,400 lightyears away. #astrophotography #deepskyphotography #deepskyastrophotography @astrobackyard @bbcskyatnightmag
SCOPE DOCTOR
Our equipment specialist cures your optical ailments and technical maladies
Email your queries to scopedoctor@skyatnightmagazine.com
What budget-friendly binoculars would you recommend to see star clusters and Saturn’s rings from my home in Kathmandu, Nepal? DONNA SHRESTHA
Binoculars are an excellent way of observing many celestial objects, including star clusters, but the planets are very small and to observe Saturn’s rings requires a magnification in excess of 20x. Even then the image will be extremely small and will show little detail; it will just be a sphere with ‘ears’.
You can buy high magnification binoculars but these are expensive and require the additional cost of a substantial mounting. Perhaps a better approach would be to purchase a pair of binoculars for star clusters and general observing and a telescope for observing the planets, other smaller objects and the craters on the Moon.
The best value for money binoculars are 10×50 types with Porro-prisms as these will allow you to observe a huge range of objects, but buy the best pair you can afford.
A 6- to 8-inch Dobsonian telescope and a minimum magnification of 50x will allow you to observe Saturn’s rings separated from the planet itself.
The purchase cost of these two instruments together would be much less than the cost of high magnification binoculars.
Steve’s top tip
What is the difference between a 1.25-inch and 2-inch eyepiece?
The 1.25-inch and 2-inch measurement refers to the diameter of the eyepiece’s barrel. Part of the construction of an eyepiece includes a metal or plastic ring within the barrel called a ‘field stop’, which limits the size of the observed field by appearing as a sharply defined circle in the view through a telescope. The maximum size of the field stop is dictated by the diameter of the barrel itself so to enjoy the widest view possible from a long focal length (low magnification) eyepiece, a 2-inch barrel can be used if your telescope can accommodate it, to increase the apparent field of view.
Steve Richards is a keen astro imager and an astronomy equipment expert