astronomy
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t remains cool enough to offer crisp clear views even though the length of our observation hours and period of true darkness begin to shorten each night. The astronomical calendar is marked this month with the passing of the Equinox. More specifically the Vernal Equinox. This occurs on the 20th. It marks a time in the year when day and night will be almost exactly the same length. The positions of the Sun at this point in the calendar will help you to mark your east and west compass points for future observing. The Sun will rise due east and set due west so you can make a mental note of something on each horizon; a tree, telegraph pole, church spire for example. Knowing these directions as a starting point really helps to locate things in the night sky. After this date the nights will begin to shorten slightly. The Moon will continue to point us towards some beautiful objects as it passes through its many phases over the course of the month. Shining a Light on Astronomy Jargon - ’MAGNITUDE’
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most important to astronomers. Polaris is This word, often abbreviated to 'Mag' in 30 times the width of our Sun. It is the astronomy circles is used to describe the Alpha star in the constellation of Ursa brightness of a Star, Planet or other object Minor - of which more in the next section in the night sky. A scale is used so that it is and it is also referred to as the North Star. possible to make a comparison between As our Earth travels around the Sun, it is two or more objects and also to make always tilted over 23.5 degrees and if measurements should an object's we drew a line through 'magnitude' change over a the North and South period of time. Every Knowing these directions Poles this would object will have a 'True extend out towards the Magnitude' and as a starting point really same point in the sky an 'Apparent Magnitude'. helps to locate things in throughout the year. The apparent magnitude the night sky This is a point is what is used on a scale extremely close to the to describe how we star Polaris. It is also therefore known as experience its brightness from here on the Pole Star. As its position points Earth. Brighter objects have a negative towards the North in this way it is a star number , for example Sirius is magnitude which has helped with navigation. -1.4 while our Sun has a magnitude of Standing at the North Pole Polaris will be 26.7 and the Moon is recorded as having a directly overhead. Standing at your front magnitude of -12.6. It is said that the door, the angle of Polaris above you will faintest stars our eyes can see, in clear tell you what your latitude is. This can be conditions are around 'mag' 6.0. useful to know when setting up some Object of the Month - POLARIS telescopes too. Finding Polaris in the Polaris, although not one of the northern hemisphere can also help us to brightest stars in the northern hemisphere navigate towards everything else in our (its magnitude is only 2.0), is one of the night sky. Once you know where Polaris is,
