dipper@utastro.UUCP (Debbie Byrd) (05/23/85)
Some comet-watchers are encouraging people to turn out their lights for Comet Halley. More -- after this. May 23 Dark Skies for Comet Halley Comet Halley is coming back -- but it won't appear as spectacular as it did on its last visit, in 1910 -- when the comet got so close, its tail brushed the atmosphere of Earth! This time, the sun will be between us and Comet Halley, when the comet reaches perihelion, its closest point to the sun. So when the comet is brightest, around February of 1986, we won't be able to see it. We will see the comet in the evening sky in January of '86 -- and in the predawn sky in March. But, in 1985/86, another source of light will make the comet much harder to see than it was in 1910. That's the artificial light of the city. City lights are the reason for a campaign launched by comet-watchers -- aimed at reducing unessential outdoor lighting for a few hours on the best nights for viewing Comet Halley. This campaign originated in 1981. It's called "Dark Skies for Comet Halley." In addition to darkening the skies for the comet itself, the Dark Skies for Halley campaign hopes to convince people that excess outdoor lights are costly and unnecessary. Some cities have already converted their street lights to those that use low pressure sodium. Other cities have an ad lighting curfew -- where businesses turn off their advertising signs after they close in the evenings. The best way to see Comet Halley will be from the country -- away from bright city lights. Still, if Dark Skies for Comet Halley is successful -- perhaps those city lights won't be quite so bright. Script by Diana Hadley and Deborah Byrd. (c) Copyright 1984, 1985 McDonald Observatory, University of Texas at Austin