Naturespeak

The night sky

Available in real and virtual versions

By Don Brett,

Whistler Naturalists

The best astronomy season is just starting: its getting dark earlier and the nights are still relatively (for Whistler!) warm. Mark your calendar for Sept. 1 to 11 when the moon is invisible or at least not obtrusive for stargazing. Plan to go out for a couple of hours on the first clear night during that period. Bring a reclining lawn chair or blanket, warm clothes, your eyes, a star chart and an optical aid (optional).

Don’t have a telescope? No problem. If you own binoculars, especially those with lenses 35 mm in diameter and more, you have excellent astronomical instruments and your view of the heavens will be dramatically enhanced. If not, your eyes and a star chart are more than enough to enjoy many nights of getting acquainted with the stars and planets.

So how do you obtain a star chart? Simple. A number of astronomy Web site offer interactive star charts that can provide a customized representation of the sky visible from any location on any given night. One such is available at http://skyandtelescope.com/observing/skychart/ .

Even better is to consider a small investment in "home planetarium software." Originally targeted at amateur astronomers to aid in planning and recording observing sessions, software houses are now offering applications with very easy interfaces, excellent graphics and amazing simulations. My favourite is Starry Night Backyard, a Canadian release available in download version for $50 (see below).

After installing and loading the program, input your location (for Whistler, 50 ^o N 123 ^o W). The software then obtains the current date and time from your computer’s clock and displays the sky as it actually looks – night or day. The sun, moon, planets, hundreds of thousands of stars, constellations, comets, asteroids, nebulae, galaxies, even satellites are shown in their actual positions and updated minute by minute. These objects can be displayed in a variety of ways including labelled, outlined, and zoomed in or out. Run your cursor over an object and a pop-up window displays copious information such as type of object, distance, key characteristics and a link to a variety of Web sites with detailed information.

I’ve found this software unmatchable to better understand the three dimensional nature and motion of the planets and stars. You can select from a variety of viewing locations such as the moon, any planet, or from outside the solar system and see what the solar system looks like. Now select the fast-forward button and watch an accurate simulation of the motions of the planets. Or select any of thousands of stars and "fly there" faster than Captain Picard. See how the shapes of the constellations change as your location in space changes. If you select "years" on the fast-forward button, you can see a simulation of the proper motion of stars through space.

You can print any section of the display to take outside for observing assistance – the software will even simulate the field of view of your binoculars so that you can better match what you see through the optics with the printed display. And if it’s cloudy or raining on the night you plan to spend outside (not a very common occurrence here), you can just fire up the computer and do some virtual observing instead!

Starry Night - http://www.starrynight.com