Free Astronomy Newsletter Free Astronomy Newsletter
Courses and more...
Yet More...

Astronomy Know How Newsletter Archive

NB Links to external sites were active at the time of publication but cannot be guaranteed

Astronomy Know How
Helping you See the Night Sky - Newsletter No. 67 May 2012
ŠAstronomy Know How 2012

Happy Stargazing!

And welcome and thanks for subscribing to this my FREE! monthly newsletter. I hope that you enjoy it.

Important news this month:

Without a doubt, the most important astronomical event of this month is the Annular Ecplise of the Sun on 20th May. There's more on this later in this Newsletter...

If you haven't seen my 'blog' yet, please take a look at I'm putting up useful bits of astronomical information and other items of interest.

Also I'm pleased to announce that my friend Tracy will be helping me to administer the blog. Tracy will pick up 'hot off the press' items of space related news for you and will be keeping the blog looking fresh. She's a keen astronomer herself. So, welcome Tracy!

I'm pleased to tell you that my novel 'In The Lion's Paw', set at the end of this year, is selling well through Amazon. If you haven't got your copy yet, please take a look at Amazon UK. You can have it as a Kindle eBook as well, both here and in America or in fact all over the world... Amazon USA

Not only all this, I am pleased to tell you that this Newsletter in not only available as a podcast from us here... But also from my friends at 'Astronomy FM' Internet Radio on Under British Skies

If you would like to keep up to date on a more immediate basis than just the monthly Newsletter, or the blog, then you can join my Facebook group
Astronomy Know How with Ninian Boyle by clicking 'like' on that page, or follow me on Twitter.

I put more up to date news and events on there. It would be great if you could join me!

I wish you clear skies,



In this issue:
  1. May Highlights
  2. The Moon This Month
  3. The Planets This Month
  4. Naked Eye Astronomy
  5. Deep Sky Highlights of April
  6. Other News
  7. News Links
  8. The Secrets of Astronomy
  9. Are you interested in Imaging?
  10. Contact Us
May's Highlights

Although it is not getting dark until quite late now, there are still plenty of things you can see in the night sky...

The planet Venus has to be the highlight of this month. It is extremely bright and through binoculars or a small telescope will show a lovely crescent phase. It is moving steadily nearer to the Sun from our point of view here on Earth, ready for its transit across the disc of the Sun in June. There's more about Venus a little later in this Newsletter and more about the Venus transit next month...

A beautiful crescent Moon will occult or pass in front of, the open star cluster Messier 67 on the 26th of the month. The best way to view this is through binoculars or a small telescope with a fairly low power eyepiece. The start of the occultation is around 21:00BST which means that it will still be twilight, so it might be tricky to see.

It will be easier to see the end of the occultation when M67 reappears from behind the Moon at around 22:50BST when the sky will be much darker. Because the Moon has no atmosphere the stars will seem to instantly disappear behind the dark portion of the Moon at the beginning of the occultation and pop into view again from behind the brightly lit side of the Moon at the end. Occultations of stars by the Moon are used to obtain the exact position and also the shape of the edge of the lunar disc.

May marks the beginning of the season to observe 'Noctilucent cloud'. These are clouds which form very high up in our atmosphere and when the Sun is not far below our horizon, as it is during the summer months in the northern hemisphere, they are illuminated and often have a 'herring bone' appearance with a pearlescent bluish tinge. They form some 100km up in the stratosphere and it is still uncertain exactly how and why they form.

You can sometimes see Noctilucent cloud an hour or two after sunset and before sunrise. You'll see them low to the northern horizon, but this is by no means a certainty as they come and go and conditions have to be right for them to form. Good hunting.

There will be an Annular Solar Eclipse on 20th May visible from the Chinese Coast, the South of Japan and the Western United States and Canada. So if you are heading to any of these destinations in time for the 20th you may well get to see it. An Annular Eclipse is a little different to a Total Solar Eclipse in that the Moon, because it is further away from us in its orbit, appears smaller than the Sun and so when it passes in front of the disc of our star, it does not fully cover it. This means that you can see a bright ring or 'annulus' around the edge of the silhouette of the Moon. So care must be taken when viewing this type of Eclipse especially. Unfortunately, those of us living in Europe will not be able to see any of this Eclipse.

Saturn is now the dominant planet in our night sky, but more on this a little later...

Back to List of Contents
The Moon This Month

The Moon gives us a waxing gibbous phase on 1st May. It is 73% illuminated and lies a little to the south-east of planet Mars in Leo. Mars is still bright enough to be seen near the brightly lit lunar landscape.

Full Moon occurs on the 6th. It will be quite low in the sky compared to other times of the year and is moving through the constellation of, Libra The Scales and will drift into that of Scorpius the Scorpion.

The 13th May brings us a last quarter Moon. This shows as the illuminated eastern half of the Moon. You can only see a last quarter Moon in the early hours of the morning. The phase is now waning towards New Moon...

And New Moon occurs on 20th May. New Moon and the few nights either side of this are of course the best time to observe the many deep sky delights which can be found all over the heavens. At other time the bright Moon has a tendency to 'drown out' the fainter and more difficult objects to see and image.

If you would like to know more about the Moon, then there is loads of information on my website here.
Back to List of Contents
The Planets This Month

Venus is now the brightest object in the sky and if you haven't yet seen it through binoculars or a small telescope, I would recommend that you give it a go. Don't wait too long though as it is now setting earlier an earlier as it heads towards its transit of the Solar disc in June.

Because Venus is getting nearer to us it is starting to appear larger as well as brighter, this is in spite of the fact that at the beginning of the month it is only showing a fairly slender crescent. It is a truly lovely sight through a small telescope. Venus is so bright because it is so reflective. The planet is blanketed in a thick layer of cloud which is highly reflective. The only way we can know what the surface of the planet looks like is through the use of mapping radar.

Venus will transit the face of the Sun in June, an event which only occurs once every 124 years and then again 8 years after this. We saw a transit in 2004 and so we are due the second viewing this year. I'll be explaining a lot more about it and how you might see it, next month.

Mars is still on view in the constellation of Leo, The Lion. However, we are moving away from the planet quite rapidly now and so it will appear dimmer and, if you plan to observe it through a telescope, much smaller than it did a few weeks ago.

The small apparent size of the disc of Mars will mean that any features on its surface will be difficult to see. However, you may still be able to detect a polar cap or the bright Hellas Basin.

Saturn is now past opposition and is heading lower into the western skies as the month progresses, so view it with a telescope earlier in the month rather than later. The famous rings are tilted towards us and are nicely on display. You should be able to see the shadow of the body of the planet cast onto the rings. You will need a fairly high power to see this well, anything from 80-150x magnification.

Back to List of Contents
Naked Eye Astronomy

A fun thing to do if you don't have any optical aid such as a telescope or even binoculars, is to use certain stars and groups of stars to help you navigate your way around the night sky.

There are several bright stars which can act a 'jumping off points' for you. This month I would like to draw your attention to the group of stars known as 'The Plough'. This group is often referred to as a constellation, but strictly speaking, is an asterism. This is a group of stars which are easily recogniseable and which may be a part of a constellation, or made up from two or more constellations. The Plough is in fact part of the Constellation of Ursa Major, The Great Bear. The seven stars of The Plough look a bit like a 'Saucepan' with a bent handle. If you follow the stars of the handle in an arc away from the 'bowl' of The Plough, the next bright star you come to is a distinctly orange coloured star called Arcturus.

The star Arcturus, lies in the constellation of Bootes, The Herdsman. The name Arcturus means 'follower of the bear'. Bootes is a constellation which looks a bit like a child's kite. In fact this 'kite' shaped part of the constellation is a well known asterism itself.

If you keep moving from the handle of The Plough, through the star Arcturus and keep going in an arc, the next brightest star which you come to is that of Spica in the constellation of Virgo, The Virgin. So you can 'arc to Arcturus and speed on to Spica'. During this month this way of finding the star Spica will also help you to find the planet Saturn. Saturn lies above (north) of Spica and has a slight 'straw' colouring and is a little brighter than Spica.
Back to List of Contents
Deep Sky Highlights of May

May starts to bring the summer constellations back into our skies and many deep-sky treats with them...

Rising higher in the south-eastern skies this month is the constellation of Hercules. Hercules was the son of Zeus and Alcmene a mortal woman, so he was a demigod. The constellation is most famous for the stunning globular star cluster known as Messier 13 or M13. This can be found between the two stars on the right hand side of the 'keystone' asterism.

From a dark sky sight on a clear night, M13 can just be made out with the naked eye as a small fuzzy patch of light. Through binoculars or a small telescope it take on a distinctly spherical appearance and with a larger telescope of say around 6-inch aperture you can start to resolve the stars in this cluster. Globular clusters contain some of the oldest stars in the Universe and M13 it is thought contains up to a million stars, tightly packed together. Globular clusters orbit their parent galaxy unlike the stars that make up the majority of the galaxy itself.

There is one other lovely globular cluster to be found in Hercules and which is often overlooked for its brighter sibling M13. This is M92. This globular star cluster forms an equilateral triangle with the two stars at the top of the 'keystone' asterism. Of course a good star chart will help you find these wonderful objects. If you would like to buy such a chart, then please take a look at my suggestions on my website which you can buy on Amazon

The other object to which I would like to draw your attention is a star. In fact it is two stars. The brightest star in the constellation, Alpha Herculis also known as Rasalgethi (the head of the kneeler) and is in fact a double star.

You can find Alpha Herculis by drawing an imaginary line from the top right hand star of the 'keystone' astersim and heading south, through the lower left hand one and then keep on going about twice that distance. It isn't a particularly bright star, but then none of the stars in Hercules are particularly bright, but when viewed in a telescope it is relatively easy to split the two components. These stars lay around 380 light years away. You may have by now realised that Hercules is standing on his head!

Back to List of Contents
Other News

'In the Lion's Paw' is now available as a paperback from a few book distributors both here and in the USA, especially from Amazon. So if you haven't got your copy yet, please go and order it now. It is also available in Kindle format from Amazon UK and Amazon USA you can also get the print version here

To find out more about the book if you would like, you can visit the In the Lion's Paw website.

Amazon readers have said:
"I read it in two sittings and couldn't put it down."
"If you only read 1 book this year make it this one."
"Once you start reading this story you will be swept along through a tumultuous week in these characters' lives... "

If you need advice about purchasing equipment, then you can email me on I'd be happy to give you a few tips and point you to the right dealer who I think can help you with your purchase. No-one else gets this help; only YOU as a subscriber to my Newsletter!

If you would like more information about anything I've mentioned in this Newsletter, please email me and I'd be happy to explain further.


If you are on Facebook, please come and be 'fan' of my page 'Astronomy Know How with Ninian Boyle'. I'm planning to use it for lots of free information and tips on how to observe the night sky and also post up interesting events as they are set up. It will mean that you'll be the first to know about really useful things connected to your hobby, so join me on facebook

Oh! and you can follow me on Twitter too

Please take a look at and put you pictures up on our image gallery here - and if you have any difficulties please contact us so we know about it and can either help you or sort out any problems. Thanks.

If there is a course or talk that you would like me to cover, I would invite you to please let me know. I'm keen to provide you with the information that YOU want, rather than that which I think you might like. So please tell me
Back to List of Contents
  Here are some links to some other recent news stories that I thought you would find interesting...

Astronomers identify three extrasolar planets
It's not little green men, but it could be a step in that direction: Cornell astronomers, using data from the NASA Kepler Mission, have identified three Earthlike planets orbiting their own suns, all of which could be hospitable to life.

Billionaire-backed asteroid mining venture starts with space telescopes
The venture known as Planetary Resources eventually plans to go asteroid mining - but the first step in the billionaire-backed business plan is to launch an orbital fleet of "personal space telescopes" capable of looking out into the heavens or back down on Earth. more...

Happy Birthday, Hubble! Space Telescope Spies Cluster of Bright Stars
A busy cosmic landscape of bright stars against a dust-filled, hazy background is the focus of a newly released image from the Hubble Space Telescope. more...

NASA's Webb Telescope Flight Backplane Section Completed
The center section of the backplane structure that will fly on NASA's James Webb Space Telescope has been completed, marking an important milestone in the telescope's hardware development. more...

How Big Data Is Changing Astronomy (Again)
The amount of data we have on our universe is doubling every year thanks to big telescopes and better light detectors. more...

Back to List of Contents
  Discover everything that you REALLY need to know about telescopes and how to find interesting things to look at in the night sky...

You can find all the information that you really need in my online course. It gives you all the essential information to be a good astronomer, without lots of jargon or difficult maths. You'll get loads of free bonuses and it also has videos and animations to help make the explanations clear and concise. So if you want to know what Sir Patrick Moore wished for...

...please take a look at my eCourse called
'Basic Astronomy with a Telescope'. It's what Sir Patrick wished he'd had when he started out in astronomy!

Back to List of Contents
  Are you interested in Imaging?

You can learn how to take stunning images of the night sky with your digital SLR camera that will amaze your friends and family with the eBook
DSLR Astrophotography - A Beginners Guide which I co-wrote with my friend Jon Walton...

Back to List of Contents
To contact us

Telephone me on +44(0)208-144-1091

or contact me by email

You are receiving this newsletter because you filled in a form on the Astronomy Know How Web site on {!sign date long} but you can change your email address by which we contact you, or unsubscribe if you no longer want the newsletter or think you have been subscribed incorrectly by scrolling down and use the link below

Back to List of Contents