The sky of May – Tahi, Rua, Toru

This is an introduction to the stars that you can see in May in general, from Wellington New Zealand. If you wish to hear about the sky of May 2016 you can listen here to my korero (story) for the May 2016 podcast (Jodcast.net)

In Maori, tahi, rua, toru means one, two, three.

Three bright stars share the evening sky in May, and you can see them in three ways when you look at the sky: with the naked eye, with a pair of binoculars and with a telescope. I like each of these methods. They are, each in their way very special and each add a layer of depth to the previous one. My first binocular was called Li. That is because according to the Chinese wisdom, a road of one thousand li starts with the first step. This is why I always recommend to never buy a telescope unless they have got naked eye stargazing or binocular observing sorted, otherwise it would be too frustrating to try and find all these deep sky objects without knowing where to look. I mean really knowing.

Even with a go-to telescope – which is what most modern telescopes are, they just find their way across the sky, and it would not feel that much fun not to know where I am pointing the lens. Not to mention that any go-to telescope needs to be polar aligned – that is a part making the mount of the telescope would have to be aligned with Earth’s axis of rotation in order for the go-to function to work.

So, what can we see with the naked eye in May?

Soon after sunset, circumpolar Atutahi / Canopus the second brightest star, is southwest of the point directly above you overhead. Tahi means One in Maori, suggesting that Atutahi is the chief of the stars and visible all night long. Takurua / Sirius, the brightest star, appears northwest of the zenith. Rua means two in Maori and Takurua is one of the two wives of Ra, the Sun. Below Takurua are bluish Puanga/Rigel and reddish Putara/Betelgeuse, the brightest stars in Orion.  Between them is a vertical line made of the three stars, Tautoru. Toru means three in Maori and it’s the name given to Orion’s belt.

Midway up the southeast sky are ‘The Pointers’, Beta and Alpha Centauri. Soon after dusk Arcturus appears in the northeast, often twinkling red and green as the air breaks up its orange light.

Crux, the Southern Cross, is southeast of the zenith, to the right of ‘The Pointers’,  Alpha and Beta Centauri. Zenith (UK /ˈzɛnɪθ/, US /ˈziːnɪθ/) refers to an imaginary point directly “above” a particular location, on the imaginary celestial sphere.

Orange Antares, right of Mars, marks the body of Scorpius, the Scorpion. Antares means ‘rival to Mars’ in Greek for the planet and star are often similar in colour and brightness, but not at this time of year.

The Milky Way, our edgewise view of the galaxy, is brightest in the southeast toward Scorpius and Sagittarius where its centre lies, and it can be traced up the sky past the Pointers and Crux, fading toward Sirius. Its nearby outer edge is by Orion, where the Milky Way is faintest.

The Clouds of Magellan, LMC and SMC, are two small galaxies midway down the southern sky, easily seen by eye on a dark moonless night. If you  use your peripheral vision, which means don’t try to stare directly at them, using the edge of your vision out of the corner of your eye will reveal more detail. It’s a trick we use in stargazing, and has to do with how our eyes are constructed. Night vision is mostly based on our rod cells (the ones responsible with detecting movement, which is also something we see very well with the edge of our vision).

Once you’ve mastered the naked eye observing, it’s time to try the next level, binoculars.

What can we see in May’s night sky with a pair of binoculars?

Binoculars come in many shapes and forms, a great size for stargazing is 7 x 50 or 10 x 50. The first number is a measure of power, it means how much these binoculars magnify, in this case the 7 and the 10.  The second number is the diameter of the objective (the big lenses at the front) in millimetres, in this case the 50. I really like binoculars, they are my favourite aids to observing the night sky because they are light, you can take them easily with you on trips, they don’t really require assembly and disassembly, no polar alignment, and visually are better than telescopes! With a tripod attached they are truly magnificent. Comets and some open star clusters are sometimes better observed with binoculars. We have two eyes, so binocular views are more spectacular in many regards than telescopic, because our brains interpret what we see, binoculars give depth of view as they engage both eyes in the process.

There are a few great objects that you could admire in binoculars. On the ecliptic, M44 – the Praesepe  is an open cluster in Cancer. Known as the beehive, the open cluster swarms with stars. It’s really fuzzy when you look at it with the naked eye and binoculars reveal a beautiful lace of stars. Praesepes are as far as 577 light years and estimated to be about 730 million years old with an average magnitude of 3.5.  Also in Cancer, M37, is another open cluster, one of the oldest known, almost 3.2 billion years.

Close to the area south of the triangle that marks Leo’s hips…M65, M66 and NGC 3628, which will be visible depending on the size of your binoculars they are also known as the “Leo Trio”. Also in Leo, M105 is an elliptical galaxy. Last but not least M96 another galaxy in Leo lies at about 35 million light years away.  You can get a map and look for all these objects. Or, if everything else fails, simply take your binoculars and swipe the Milky Way from one edge to the other. You might not figure out exactly which objects you are looking at but you would definitely find amazing sights, especially in the region close to Carina. You will find there IC2602, NGC3114, NGC353, NGC2516 that are all open clusters then in Crux NGC4755 which is another open cluster, NGC2451 in Puppis, and IC2391 in Vela.

Lower down, Omega Centauri, is a globular cluster in Centaurus and in Scorpius, there are the Butterfly Cluster, M7 open cluster and NGC6231 open cluster.


What you can’t see:

  • Aries (Sun in Aries from 19th of April to 14th of May) and
  • Taurus (Sun in Taurus from 15th of May to 21st of June)

 

Horoscope  with Precession
Zodiacal Band

This is the Zodiacal band, an awesome drawing by Eugene Georgiades. Since one thousand years ago, when people stopped taking precession into account, the zodiacal constellations have shifted. Yes, we are once again not what we think we are. Here is an excellent site with more details about your real star sign.


Featured cool sky atlas: the Philips’s Night Sky Atlas

One of my bibles in terms of what to see in the night sky is Philips’s Night Sky Atlas, by Robin Scagell and with maps by Will Tirion. And every time someone asks me what telescope to buy and I ask them if they do have a pair of binoculars, if the answer is no, then I always say don’t buy a telescope if you have not looked at the sky with binoculars. Even if you only used them to locate objects that are too faint for the naked eye or hidden by light pollution. Some of the best views of the larger star clusters, bright nebulae and comets are best seen in binoculars. 

May you enjoy clear and dark skies so that you can see the stars and remember that we are made of the same star dust as they are!

Kia Kaha and clear skies from Aotearoa New Zealand


Credits: Alan Gilmore and Toa Waaka

http://www.space.com/26021-best-binoculars.html

http://www.space.com/27404-binoculars-buying-guide.html