Sky Maps
Can you imagine traveling in a strange country, in a new car, driving on the “wrong” side of the road with no street signs available anywhere? And, of course, no one knows your language! This is how navigating the sky and hoping to find a specific celestial body would be, without sky maps. Even the most experienced astrophysicists would be lost without some form of sky map.
Sky maps are exactly what they say they are. They are detailed maps of the sky. Sky maps today can help the amateur and professional astronomer. Their primary purposes are these:
1. Locate planets, star and the 88 constellations.
2. Locate star clusters, nebulae and distant galaxies.
3. Locate and follow comets across the sky.
4. Learn about the night sky and astronomy.
There are many different kinds of star maps and many ways to locate them. The easiest type of star map to read, but also the least detailed, is a planishere. These are simple, round, rotating star maps of the night sky. They are typically hand held and can be rotated to your hemisphere.
There are also naked eye sky maps. They are exactly what they say, as well. They provide locations of all celestial bodies that can be viewed with the naked eye. Think, the moon and the big dipper. Find a circle map for naked eye searches. These show the sky in your area from horizon to horizon. Circle sky maps will make your search much easier if you find that naked eye searches are what really brings you pleasure in astronomy. This is the case for many people.
Next, come the more detailed maps that typically need at least binoculars or a telescope to view what they reveal. A basic atlas will show stars to the 6th magnitude. A detailed atlas will show the location of stars that are to the 9th-11th magnitude. These can only be viewed with a telescope. The granddaddy of all sky maps is the Megastar! They chart stars all the way to the 15th magnitude. Some of them over a million deep sky objects! That is really incredible.
Finding these maps are fairly simple. By subscribing to a monthly astronomy magazine, you will get an updated star map every month. Simply find the one that fits your hemisphere and you’re good to go.
Another good resource is the Internet. There are countless websites that will provide a star map and some are even free! The ones that aren’t free are pretty wallet friendly. An excellent site for maps online is www.astroviewer.com.
A very important side note to using a star map, is to make sure that you understand how to read them. Make sure that you hold your map the correct way. The direction that you are facing should be pointing toward you if you are holding the map horizontally. If you are holding the map vertically make sure that the direction you are facing is placed at the bottom of the map. If not, then it would be like trying to drive to Florida while studying a map of New York!
Like earth maps, sky maps have direction points to help you find your way. Like earth maps, also, sky maps use counterpoints to help the reader “see”. While sea and land maps use latitude and longitude, sky maps use right ascension and declamation. These will intersect and allow you to find object much more quickly.
I would also recommend purchasing a red filter flashlight. When you are outside, in the dark, trying to locate a very small point on a map, well, it’s a little tough without some form of light. Standard light will hinder your ability to see anything in the sky. Since red lights do not interfere with night vision, the red filter on your flashlight will allow you to read your sky map without interfering with your star gazing!
There is nothing like viewing the night sky. Finding and locating the constellations and understanding what you are seeing is almost surreal. A nebulae, first viewed and never before seen by your eyes, will amaze you. It will be even more astounding if you intentionally find it and know what you are seeing. Purchase a simple map at first and move up! You won’t be able to stop star gazing after that!
Resource: www.harvard.edu
