May Night Sky

The spring night sky has well and truly sprung, and although these months are sign of brighter evenings and therefore later bedtimes if you want star gaze, there are still lots of interesting patterns and objects that we can see. So let’s delve in and find them.

The spring night sky patterns are not as bright and easy to spot as those in the winter night sky but do not let this dismay you; this can really test your skill at navigating the stars. One of the most well-known tricks for finding your way around the spring night sky begins with the well-known asterism, the Plough or the Big Dipper. First begin by finding the bright 7 starred saucepan like pattern and then trace the handle of it. Now you follow the curve of the handle beyond the end until you arrive at a very bright orange star. This star is called Arcturus, so you ‘arc to Arcturus,’ the first stop on our spring night sky trip.

 

Arc to Arcturus. Image Credit: Kerry Scullion, Stellarium

 

Arcturus is an orange giant star that is the 4th brightest in the entire night sky, with an apparent magnitude of -0.04, so it is very easy to spot. Arcturus was actually the first star seen in the day time (after the Sun of course) by the French astronomer Jean-Baptiste Morin back in 1635.

Believed to be over 7 billion years old, this orange giant star is in the later stages of its life as it is thought by astronomers that it has used all of the hydrogen at its core, triggering the days of decline for any star!  It will eventually puff its outer layers and form into a small white dwarf star surrounded by a gorgeous planetary nebula.

The name Arcturus is Greek word meaning ‘Bear Watcher’ or ‘Guardian of the Bear’, and this could be related to one of the myths of the constellation that Arcturus is found in, Boötes. Boötes is a Greek word meaning Herdsman and the name itself is quite strange to pronounce. Each ‘o’ has to be pronounced and the second syllable has to be stressed, so it sounds like ‘Bo-OH-tez.’

At this time of the year Boötes can be found in the Southern sky and It wouldn’t be advisable to try and spot a human shape in the pattern. Instead try and spot an ice-cream cone which is the shape of his body. Like all constellations in the night sky, there are many myths linked to Boötes but the saddest story is the story of Arcos who many believed Boötes to be based on.  Arcos was the son of Zeus and Callisto, the daughter of the Arcadian King Lycaon whom Arcos was actually raised by. You would think that his grandfather would love him very much if he raised him, but alas King Lycaon killed Arcos and planned to serve him as a meal to his father Zeus!  Zeus found out about this before he had the meal and was so enraged he turned the King into a wolf and killed all of Lycaon’s sons. He also brought his son Arcos back to life.

You would think the story ends here but that was not to be. Zeus’s continuously scorned wife Hera found out about his infidelity, and like many of the other Myths, didn’t punish the king of the gods but his mistress instead by transforming Callisto into a bear. Many years later when Arcos was all grown up he was hunting in the woods and came across his mother in bear form, but he did not recognise her. So he hunted her! She managed to flee to a nearby temple for protection and before an awful tragedy could occur, Zeus took them both and placed them into the sky. So in this myth, Callisto is the Great Bear Ursa Major and Arcos is Boötes the Herdsman.

Moving on from very sad story, let’s take a look at the constellation that Boötes seems to hold the reins to, Canes Venatici, the herdsman’s dogs. We are inching closer to the summer months when we can find an abundance of globular clusters in the night sky, and the spring night sky lets us have a peak at the earliest clusters visible from the Earth. In Canes Venatici, one of the best studied globular Clusters can be found, Messier 3 (M3). Discovered back in 1764 by Charles Messier this deep sky object is a huge group of stars, around 500,000 stars held together by gravity. It is one of the largest and brightest globular clusters that can be seen in the night sky with and apparent magnitude of +6.2. It is also a very old object with astronomers believing it to be 8 billion years old. You will need at least a small telescope to really see the beauty of this object, but good and powerful binoculars will be able to pick it up.

 

Messier 3 discovered by Charles Messier. Image Credit Sky Center Uni

 

Now, we are going to go back to the brilliant orange star that is Arcturus and we are going to use it to find the next constellation in the night sky, Virgo. To find it, from Arcturus we are going to visually ‘spike to Spica,’ the brightest star in the giant maiden. Spica is a Latin word that mean ear, and when you observe the artwork of Virgo you will notice she is holding an ear of corn, right where Spica is located. Now the best thing about finding Spica in May this year is that it has a bright planetary buddy sailing the sky next to it: the largest planet in our solar system, Jupiter! Jupiter located just to the right and slightly above Spica but it would be hard to miss as it is so bright. If you have never seen a planet in the night sky then the best tip is to look for a very bright star like object. Some of the planets appear even brighter than the real stars around them as remember; they are closer to us than the stars. And Jupiter is particularly bright thanks to its size and its brilliant clouds that reflect the light so well. Its apparent magnitude is -1.61 so it is easy to spot. If you get a pair of binoculars you can see its 4 largest moons, known as the Galilean moons, after Galileo who discovered them in 1610. But Jupiter has many more moons, 67 in fact, making it not only the largest planet in our solar system, but the planet with the most moons. A small telescope will reveal a nice view of the lovely bands around Jupiter, with the lighter coloured bands referred to as zones and the darker ones referred to as belts. As well as these Jupiter has many storms, including its most distinctive feature, the Great Red Spot and the smaller 3 White Storms. Jupiter is a stunningly beautiful yet a tumultuous planet that should never be ignored when it is in the night sky.

 

Spica and Jupiter, Image credit: Kerry Scullion, Stellarium

 

Moving on from the king of the planets, we are now going to do the final part of our dance across the spring constellations. So find your way back to Spica and from here we will ‘leap to Leo,’ until we arrive at its brightest Star, Regulus! Now Leo dominates the night sky in spring as it has the brightest stars of the spring constellations. The best way to find him if you don’t follow the little night sky dance that we have been doing, is to search for a backward question mark in the southern  spring sky. Then join the bright stars around it until you find the sphynx shape and then you have found Leo. The bright star Regulus that we have leaped to is impressive on its own. Regulus is Latin for ‘prince’ or ‘little king’ and rightly so as he is the brightest of his own little star system made up of 4 stars in total, Regulus obviously being the brightest. Regulus is a star that is close to the elliptic, the path that sun appears to travel around the Earth and this means that it is a star that is often occulted by the moon and sometimes even Mercury or Venus. This is when it is hidden by the objects appearing to block our view of the star, similar to an eclipse but obviously not as noticeable. Also anyone who is a Harry Potter fan may have noticed that you recognised the name Regulus, a character name in the Harry Potter Series. Well it is believed that Rowling took much inspiration from astronomy, from Regulus, to Luna and the best (in my opinion) being Sirius, which in astronomy is the brightest star in the whole night sky and can be found in Canis Major, the Great Dog during the winter months. (Only fans of the series will understand the importance of this!)

So we have navigated our way around the best known spring constellations by following  ‘arc to Arcturus,’ ‘spiking to Spica’ and finally ‘leaping to Leo.’ So although it may be harder to spot constellations in the spring time, there is a way to easily navigate around them.

 

 

Article written by Kerry Scullion, Education Support Officer

Kerry Scullion, Education Support Officer