April 2018 Thatcher Returns!

The Night Sky April 2018

The Lyrids Meteor Shower

This month, (22nd & 23rd) the Earth will pass through the path of Comet Thatcher which orbits the sun every 415 years (Not Margaret making a fiery return, but named after the astronomer who discovered it in 1861!)

As the Earth goes around the sun we cross its path at the same time each year. The comet leaves behind a trail of small fragments and when they hit our atmosphere at 110,000 miles per hour they streak across our night sky. Tiny grains travelling at massive speeds can create huge streaks across the sky, that can last seconds. The pieces all seem to originate from the same place in the sky called the radiant. The radiant is very close to the constellation of Lyra, hence the meteor shower being called the Lyrids.

It is always best to check if the moon is going to drown out the sky. If you can wait until the early hours, the moon will have set and you should be treated to the display – always providing it is clear! Try and pick a spot that has a wide view with the radiant in front of you. Get a reclining chair or even a sun lounger to be really comfortable. Instead of staring at a single point, relax your eyes as the steaks may not appear immediately from the radiant but travel across the sky to suddenly light up. If you have never done this before I really recommend you try it. So how many will you see? About 10 to 20 per hour, although all meteor showers are hard to predict.

There are other Meteor Showers later this year and the great news is that the two main and reliable ones will take place without the moon spoiling the show! I’ll let you know nearer the time.

Lyra

This month, looking North East from Embsay towards Grassington over the Yorkshire Dales National Park, you will see a small constellation which rises successively higher each night - called Lyra. It is quite difficult to spot but does have quite a brilliant star included within it called Vega to help us find it. This star is the 2nd brightest star in the Northern Hemisphere. Believe it or not, it was once the pole star in 12,000BC and will be again sometime in the distant future. The constellation is associated with Greek mythology. Lyra, the musical instrument, was played to drown out the call of the sirens by the Argonauts as they sailed past where many had crashed on the rocks.

I’ve included 3 main sources of information or tools that I use regularly to help me understand the night sky.

Philip’s 2018 Stargazing. Month-by-month Guide to the Night Sky. ISBN 978-1-84907-464-3

This is a great summary of the highlights to look out for each month.

Stellarium Planetarium Software. (Free)

This displays a realistic view of the night sky on your computer. You can change location or date- like your very own time machine!

Astro Panel Android App

This small programme for your mobile will tell you about cloud cover and moon phase. I use this all the time as it gives you three days’ advanced warning of a clear night! Well, it is as good as anything can predict, given our weather!

March 2018 Leo

The Night Sky March 2018

There are two interesting things to spot and identify this month, the constellation of Leo and an excellent opportunity to spot two planets.

Two full moons appear this month, one at the beginning of the month and one at the end (the second called a Blue Moon, as it is rare.) The new moon is on the 17th March and the days either side are the best time to observe the night sky without the glare of the moon.

As I stated in a previous article we are very lucky to be able to see our galaxy, the Milky Way, on a dark night in Embsay. Imagine it being like a huge catherine wheel spinning around. As it spins, it leaves four great arcs or ‘arms’ that spray out to make up a huge plate shape. When we observe the Milky Way we are actually seeing one of these four arcs, which is a band of material made of stars, gas and much more than we can currently detect or understand. This month, however, I am going to ask you to look away from it. This is because we can then see deep into intergalactic space. We are going to look in one of these areas away from our galaxy in order to find a lion!

The Constellation of Leo.

Leo is a constellation rich in many galaxies and it is easy to find. Look South East (from Embsay over the top of the quarry) and half way up in the sky there will be what looks like a large backwards question mark! This forms the lion’s mane and the triangle of stars to the left are its hind quarters. In Greek mythology this is the lion killed by Hercules. The bottom bright star of the inverted question mark is Regulus. Another good way of finding Leo is to use the pointer stars as described in my January article. Draw an imaginary line from the pointer stars, one end of the line points towards Polaris and the other end, you’ve guessed it, points to Leo. If you have binoculars you may be able to spot The Beehive Cluster close by, also known as M44. It is a cluster of dozens of stars. With a telescope you may be able to find the Leo Triplet, three faint galaxies together. (See my diagram for help in locating these).

Venus and Mercury.

Normally it is quite difficult to glimpse Mercury as it is the planet orbiting closest to the sun. However, during this month when the sun goes down, it will be positioned perfectly to try and spot it. The planet Venus will be a help as both will be visible around 15th March at sunset. The best chance to spot them will be from higher ground (Embsay Crag would be perfect if it wasn’t pitch black on your way down!!) and looking West low down in the sky. Venus will be the brightest point of light and above it will be Mercury. The space probe Messenger visited Mercury in 2011 and took close to 100,000 images in order to map its whole surface. It is difficult to spot because it is roughly 48 million miles away and only about 3000 miles in diameter, which is only a little bigger than our moon.

Your easy challenge this month will be to spot Venus, then a slightly harder one to spot Mercury.

If you have binoculars or a telescope, The Beehive Cluster is challenging with the Leo Triplets being a brilliant achievement to spot. After many years of searching myself, the first time I spotted the Leo Triplets was relatively recently when I stayed in a bothy in a farmer’s field in Galloway. An astronomical wonder and well worth the effort!

Don’t forget BST begins 25th March 1am clocks spring forward.

February 2018 Orion

Even after being a keen astronomer for many years, I still find some very simple concepts and facts surprising. For example, you would think that on a clear night you would be able to see many things far out into space. In some respects, this is correct as you can see thousands of stars. But our galaxy, the Milky Way, has approximately two hundred billion stars. You are only seeing a very small percentage of it (0.000003%) which are objects either relatively close or large. It is possible to see between and beyond these objects to other galaxies, but it is hard with just your naked eye.

Looking for planets in the sky.

In the main, planets all follow the same arc across the sky called the ecliptic. So if you know where the arc is in the sky and follow it, the planets are not very far away. This is because planets were created from a thin disc of debris circling the sun. The position and angle of this disc set in place the planets’ orbital plane when they were formed. The sun and moon also appear to follow this path through the sky. I will come back to how to spot planets later on in the year when we are able to spot one or two.

Orion

Last month I showed you how to find Polaris (The North Star). This month we will be looking across the sky towards the south-west to find another familiar constellation, Orion.

Orion dominates the winter night sky. It will be familiar to many and is shaped like a very large figure eight (or hourglass). Orion is named after the hunter in Greek mythology. In more light-polluted areas of Britain, many people will only be able to see the figure eight part of Orion. However, in and around Embsay we are lucky enough to see all of the constellation due to our crisp clear skies, particularly around the time of a New Moon (15th February) as he holds a shield in front of him with one arm and a weapon with his other arm above his body.

If you look closely at the top left star of his Orion’s body you will observe a star called Betelgeuse. This star looks very different to others in the sky. It seems to be a reddish/orange colour and very bright. It is a red ‘supergiant’, meaning one of our largest known stars. It is a sun at the end of its life and has used up all of its supply of fuel. The light from Betelgeuse takes so long to reach us (600 years travelling at the speed of light) that we are seeing it as it was 600 years ago - in the year 1418 when Henry V was on the throne! It may have already exploded into a supernova but don’t worry, this will not endanger us on Earth as it is too far away. Interestingly, some astronomers believe during the explosion the brightness could be as great as our Moon for a short period.

All of the other main stars that make up Orion are young blue stars. The bottom right of the figure as you observe is called Rigel. Orion’s belt is the three stars at the centre of the constellation. This ‘belt’ has a sword which hangs down from it. On clear nights you will see it as a bright smudge. It is made up of gas and dust and is called a Nebula. This is where new stars are born. I have included an image I took of the Orion Nebula taken from Embsay on December 15th 2017.

Your challenge this month is to find Orion then his shield and weapon above him. It won’t be difficult to spot the supergiant Betelgeuse.

A harder challenge is to spot Orion’s Nebula. Good luck!