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The Sky This Week
U.S. Naval Observatory's Weekly Blog
The Theft of the Night
by Geoff Chester, USNO Public Affairs
25 August 2022
The lights of Washington, imaged from Thouroughfare Mountain Overlook, Skyline Drive Mile 39, Shenandoah National Park.
Imaged with a Canon EOS Rebel SL2 DSLR. The U.S. Capitol dome is 80 miles (130 km) from the overlook. Jupiter is the bright object to the right.
The Moon returns to the evening sky as August reaches its end. New Moon occurs on the 27th at 4:17 am Eastern Daylight Time. Luna’s slender crescent should appear low in the western sky shortly after sunset on the evening of the 29th. If you have a clear low western horizon to the west, look for the elusive planet Mercury just over five degrees below the very young Moon.
I have just returned from a few days’ vacation along Virginia’s Skyline Drive, a site I haven’t visited in over twenty years. I am happy to say that the night sky above the Blue Ridge Mountains is still quite dark, but it has become a bit more degraded since time of my last visit. The main culprit is light pollution, which has raised noticeable domes of light along many parts of the horizon. The largest of these is produced by Washington, DC and its surrounding suburbs and exurbs, which are gradually spreading closer to the boundaries of the Shenandoah National Park. In previous visits the Washington light dome was the most prominent, but now several more are springing up along other parts of the mountain horizons. These domes are not only detrimental to stargazers, but they are also graphic demonstrations of our excessive energy appetite. Those photons that light up the sky are “wasted” energy, only “useful” to lighting up the bellies of airplanes and migratory birds. Those photons can be translated into billions of dollars of wasted municipal funds as well as vast quantities of carbon emissions. However, the situation is not beyond our control. Sensible use of outdoor lighting can drastically lower the amount of light going up into the sky. Taking part in programs such as the
Globe at Night
can help raise your own awareness of the issue, and supporting organizations such as the
International Dark Sky Association
(IDA) helps to bring the subject to state, local, and national government agencies. The U.S. Naval Observatory, along with dozens of other major observatories, are long-term supporters of IDA and its mission.
As the summer vacation season winds down, this is a good time to enjoy views of dark skies from remote locations. While Skyline Drive is a wonderful place to view the sky, there are a few place a bit closer to Washington. One of these sites is the aptly named
Sky Meadows State Park
near the town of Paris, Virginia. On the evening of the 27th you can visit the park and enjoy a presentation by a JPL Solar System Ambassador, then look through dozens of amateur telescopes at the wonders of the summer skies.
In addition to the “deep sky” targets that will be visible at Sky Meadows, Saturn and Jupiter will be on display for those who wish to stay late. Saturn will command most of the attention thanks to his amazing system of rings that make him such a unique sight. They are easy to spot in small telescopes, but larger instruments will reveal more of their fine detail. Jupiter rises at 9:00 pm and should be high enough to look at by 11:00.
You will find Mars high among the stars of Taurus this week. The red planet is still best seen in the early morning sky as morning twilight begins to gather.
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