NAVIGATING THE NIGHT SKY
Using nothing but your eyes and a good star map, the stars above your head will begin to take shape
Finding your bearings beneath the night sky is an essential first step to becoming familiar with it. It’s important that you begin by viewing the night sky from a relatively dark location, free from direct sources of light, such as kitchen windows, the glare of security lights and streetlights. Your eyes need to adapt to the darkness so that you can see faint objects, otherwise you’ll be restricted to seeing just a handful
Understanding magnitudes
All celestial objects are allocated a brightness known as ‘apparent magnitude’, indicating how bright they appear. The scale works backwards in that the lower the magnitude number, the brighter the object. For example, a star of magnitude 0.0 is brighter than one of magnitude +1.0, while an object of magnitude -1.0 is brighter than one of magnitude 0.0. Each jump in magnitude corresponds to a 2.5 times increase in apparent brightness.
Objects fainter than Polaris prove more difficult to see from urban locations. From the suburbs you’ll most likely consider it a very good night if you see objects down to magnitude +4.0 with the naked eye. The faintest objects visible without an optical aid from a really dark site are around magnitude +6.0, providing your eyesight is excellent. of the brightest objects. Some people can find a convenient dark spot in their garden where much of the sky can be seen, while some find themselves in such a hopelessly light-polluted spot that there’s no option other than to venture away from their home in order to enjoy darker skies.
You don’t need to refer to detailed celestial coordinates, right ascension and declination to find and identify the brightest stars and constellations – all that’s required is a basic map of the stars with which you can compare your view. Once you’ve found Polaris and the two brightest circumpolar constellations, you can extend your exploration further afield by using a star map – be it a manual planisphere, star chart, printout from a computer program or a live interactive view on a smart device.