by Joan Marie Galat
Author of the Dot to Dot in the Sky books - blending astronomy with ancient mythology
While delivering astronomy presentations at schools in southern Alberta a few weeks ago, I took advantage of the opportunity to ask my elementary age audiences two simple questions. How many of you have heard of a supernova? How many have heard of a black hole? While I was surprised to see how many hands went up in the Kindergarten to grade three groups, I was not surprised to see their interest in the night sky. Exploding stars are exciting! Black holes fill imaginations with "what if" questions.
Although exploding stars are rarely seen and black holes are invisible, there are many other objects in the night sky to enjoy. You can see the Andromeda Galaxy with the naked eye, as well as Mercury, Venus, Mars, Jupiter, Saturn, and the 88 official constellations.
Unfortunately not everyone can enjoy the celestial wonders that should be visible on a good dark night. Those living in brightly lit cities and towns face light pollution strong enough to make dim stars less visible, constellations difficult to identify, and dark sky objects impossible to see. Even those in rural communities may find their night sky lit by yard lights, traffic, and nearby communities.
You can help reduce light pollution in a number of ways:
-stop using lights to decorate outdoors
-never use more light than you need
- choose lower wattages whenever possible
-close curtains at night to prevent light from trespassing outdoors
-consider whether you can be more selective about when you use outdoor lighting
-ensure outdoor lighting only illuminates the area you need lit
-turn off lights when they are not needed
-encourage others to be aware of their use of lighting.
Discover more strategies to reduce light pollution from the International Dark-Sky Association.
Earth at night
Credit: NASA Earth Observatory/NOAA NGDC