December 9 – 22, 2019
Mount Washington — Today’s sunset, earliest of the year, down to the second, is at 4:21:14 p.m. Sunset time is seconds later beginning tomorrow, until it is nearly one minute later, 4:22:04 p.m. on Dec. 15. Afternoons will be noticeably lighter by month’s end. But darkness is increasing in the morning. Sunrise today, 7:10:02 a.m., is 10 minutes earlier than the latest sunrise, 7:20:32 a.m. on Jan. 13.
By 5 p.m. tonight, planet Venus’ light appears as the Evening Star in the afterglow of sunset above the southwestern horizon. Also following in the path of the Sun, planet Jupiter, below and to the right of Venus, is dimmer. Binoculars will help locate Jupiter before it sets at 5:18 p.m. today; it will soon disappear from view. Saturn, faint compared to Venus, is a few degrees above the Evening Star today and closest tomorrow and Wednesday. Going forward, Venus climbs higher above the skyline and Saturn loses altitude. Venus sets at 6:24 p.m. this evening; Saturn at 6:39 p.m.
December’s Full Cold Moon reaches full phase at 12:12 a.m. EST on the 12th. Rising and setting times for horizon views follow. (For hilly landscapes, add as much as an hour to these times for moonrise and subtract for moonset.) Plan to meet the round moon glistening with reflected sunlight when it rises at 4:11 p.m. on Wednesday the 11th, sets at 7:28 a.m. on the 12th, and rises again that evening at 4:57 p.m. Find a location with unobstructed visibility to both the east and west to enjoy the thrill of observing sunrise opposite moonset and moonrise opposite sunset.
Even though moonlight this year will overwhelm the light of many Geminid meteors, begin to look skyward every night at about 9 p.m., facing away from the moon. The optimum hours to see the Geminids are midnight until 4 a.m., with best viewing at 2 a.m. Peak activity is predicted to be overnight Dec. 13-14.
The Winter Solstice occurs at 11:19 p.m. EST on Saturday, Dec. 21. Observe sunrise at its furthest south of east location for the year and sunset furthest south of west. Appreciate the Sun’s short arc above the horizon. Savor daylight – 9 hours and 6 minutes – and the longest night of the year, 14 hours 54 minutes of darkness.
Be vigilant about protecting the night from light pollution. Switch off every outdoor light between uses. Prevent light trespass. Shade indoor windows. Join the work of the International Dark Sky Association https://www.darksky.org/
Opportunities to participate
International Meteor Organization – https://is.gd/IMOvisual
Geminid meteor shower guide – https://www.space.com/34921-geminid-meteor-shower-guide.html
See the short arc of the sun at winter solstice – https://www.timeanddate.com/sun/@4938157
International Dark Sky Association – https://www.darksky.org/