Here's a proposed "fast" to give up wasteful light. Peruse the 100-plus ideas and examples to become more aware of wasted light's impingement on the natural order. Then act to lessen your impact on the night.
100+ Ways to Give Up Light
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Value the night; go with less light.
"Featuring a list of action items, Light Fast combines secular and sacred endeavors to conserve light at night. Light Fast entreats you to take inventory of your light consumption, pare your waste of photons, and enlist others to value darkness for the benefit of creation. Whereas some people give up a vice for Lent, only to return to consumption afterward, Light Fast encourages you to give up wasteful light for good--'for good' in the sense of forever as well as 'for good' in the sense of for the goodness of all."
-From blog post Light Fast Encourages Awe and Wonder