Orion

What’s Up? The Night Sky this February

Each month I will highlight a few easy things for you to spot in the night sky. These will be visible with the naked eye.

In February I will focus on the prominent constellation of Orion. It contains some fascinating objects and right now something unusual is happening there – something that may not occur again in your lifetime – so it’s worth a look! 

Orion the Hunter

In February Orion rises mid evening and dominates the southern sky. To help you spot it – here is a diagram:

Diagram of Orion's Belt

The easiest part to locate first is probably ‘Orion’s belt’ –  the three stars at an angle across the middle section. From there you should be able to make out the rest of this magnificent constellation.

(In case you weren’t aware, the stars that make up constellations are not associated with each other in any way: they are not close or interacting. They just happen to form a certain pattern when viewed from Earth.)

Having located the belt, look to the star at the bottom right, Rigel. It should appear ice blue. This means it is relatively hot which in turn means it is relatively young. In fact Rigel is a mere 10 million years old- contrast that to our Sun’s age of around 4.5 billion years.

Which brings me to the star you need to take a look at in particular this month. The star in the upper left of Orion (his shoulder) is named Betelguese (Beetle Juice!). It appears a reddy-orange colour and is therefore relatively cooler and therefore old. You should be able to spot that it is red- or certainly a different colour from Rigel.

(Stars have different lives depending upon their size- or strictly speaking their mass. This is a huge-mass star and it is bloating out as we speak. And has done for millions of years. If it was in place of our Sun it would engulf the orbits of all the planets out to Jupiter, including Earth of course.)

This diagram compares a range of stars (not all in Orion) giving you a sense of its size in comparison to our Sun and Rigel.

Star sizes

When large mass stars, like Betelgeuse die they do so in spectacular fashion. They go BANG in a big way! This is called a Supernova explosion. Astronomers have photographed many such events in other galaxies but never in our own Milky Way galaxy. Betelgeuse is the main candidate and it could happen as you are looking up this evening – or in the next few hundred thousand years. So really, any day now!

When this occurs it will appear as a bright light in the sky – brighter than the full moon for a few days and visible during the day. It will gradually fade over a few weeks.

And I mentioned something unusual is happening in Orion- it relates Betelgeuse. Since mid-December it has been fading. The difference is clearly visible and if you take a look over the coming nights it doesn’t really appear to be the bright star that it was just a few weeks ago. Astronomers don’t know the exact cause – but it could be a sign that it is about to go bang! So put your coat on and go outside!

Other Objects in Orion

Just below the belt is one of the most spectacular objects in the night sky- the Orion Nebula. This huge cloud of dust and glowing gases is visible with the naked eye. I have a stunning image of this nebula on my website.

(Astronomer use ‘averted vision’ to see faint objects. Look where you think the object lies and then instead  look slightly to the side of the object – you will then have a much improved view.)

Not exactly in Orion but close by is the star Sirius or The Dog Star. (It is part of the constellation Canis Major- the greater dog.) You can spot this below the constellation of Orion and is the brightest star in the sky. (Note it is also blue!)

There are many other beautiful objects in Orion which are not visible to the naked eye. Here is an image of The Horsehead Nebula which I processed recently and launched as part of my Galaxy on Glass range.

 Horsehead Nebula

Here is an image I took of a Supernova remnant –  the remains of a star which exploded 8000 years BC.

Supernova Remnant

One final thing to look out for. Have you wondered what that bright object is low in the sky after sunset? You will see it still throughout February and it is the planet Venus. If your eyesight is good enough you will notice it is phased, like the moon. Easy to spot with binoculars if not!

 

Enjoy the winter sky, see you next month and do view the beautiful images from deep space at www.galaxyonglaass.com

 

CHRIS BAKER