Night Sky Planisphere - 20-30 North

Night Sky Planisphere - 20-30 North

For anyone even remotely interested in the night sky, one of the essentials is learning to locate the constellations at any time or date. How do you do that? It's as simple as a rotating basic starchart called a planisphere. While it would be easy to think they're all created alike - they're not. For beginners, you need to look for one that's easy to use and to read.

If you've ever looked at a starchart in a magazine, you'll remember the dark background with white stars. This is great for planning an evening, but not for use in the field. Turning on any kind of white light will seriously impair your night vision and charts of this type need white lighting to be seen. If you look at a conventional star chart, you'll see a white background with dark stars, constellation lines, objects, etc. This design was meant to be used with a red-lensed flashlight (another astronomy staple!) which helps to preserve your night vision and still easily read the maps. "The Night Sky Planisphere" by David Chandler uses a white background with dark blue print to help you along the way!

As you progress outdoors at night, you'll find yourself using your planisphere and you'll quickly notice the impact the environment has on its construction. It's great to use paper or cardboard planispheres to start a class along the road to learning, but it won't take long until dew or ambient moisture warps your planisphere, rendering it useless. David Chandler thought about that when he designed "The Night Sky Planisphere" and added a heavy-duty plastic cover! With just a little proper care, this planisphere will endure for years.

Because we live on a round Earth and the sky appears as a dome, some areas of the sky will look "stretched" when a chart tries to convey a round object as flat. David Chandler's planisphere also eliminates over 90% of the distortion that other star wheels introduce as a result of trying to flatten out the whole sky into one map. According to Mr. Chandler, on conventional star charts constellations near the southern horizon are stretched by more than 6 to 1 for observers near Miami or Honolulu!

Because there are so many stars and constellations to be listed, reading some planispheres can be confusing. "The Night Sky" is made up of two maps, one on each side. The chart for observers facing north is located on the front, and if you are facing south, just turn the planisphere over. The easy-to-read objects on the planisphere include constellation names and outlines, bright stars, the Milky Way, selected deep-sky objects like galaxies and nebulae, the ecliptic (planets follow this imaginary line) and coordinate grid lines that help one to cross-reference with star atlases if desired. Planets are NOT depicted on the star wheel because they move across the sky independent of the stars. If they were shown on this chart, it would need to be "upgraded" more often than computer software....and that would not be a good thing!