By Dr. Bob Doyle, Frostburg State Planetarium

Geminid Meteor Shower, Winter Begins, Shortest Day and Line Up of Jupiter & Saturn low in Southwest Dusk


December begins with an Oakland dawn beginning at 6:16 a.m., sunset at 7:19 a.m., sun in South at 12:07 p.m.,
sunset at 4:55 p.m., dusk ending at 5:57 p.m., with daily sunlight lasting 9 hrs. and 36 min. The sun is in the star group
Ophiuchus through December 17, then moving into Sagittarius on December 18. December 31 has an Oakland dawn
at 6:34 a.m., sunrise at 7:38 a.m., sun is in the South at 12:21 p.m., sunset is 5:04 p.m., dusk ends at 6:06 p.m., giving us
9 hrs. and 26 min. of sunlight.

The year’s best meteor shower is called the Geminids, occurring on the night of December 13-14. The meteors in this
shower can be traced back to the star group Gemini, appearing above the star group Orion. This will be an especially
good year for the Geminids as the moon will be nearly absent from the night sky then. Meteors are usually caused by
the incineration of meteoric grit as the Earth plows across the orbit of a comet. The Geminids are connected with
the debris associated with the asteroid Phaethon (#3200). As many as 100 meteors per hour may be seen.

Winter officially begins in the early morning hours of December 21, when the sun peaks at 28 degrees in the South
around 12:15 p.m. This day has the least amount of daylight of 9 hours and 23 minutes that actually extend from
December 18 through 25. The official name is Winter Solstice, meaning ‘standing still’ as the rising and setting points of
the sun seems to be stuck along the horizon. Once we get into winter, the rising and setting points begin to move
northward. As we approach spring, the motion of the rising and setting points is most rapid, then slowing down as we
approach summer for the Summer Solstice.

The giant planets Jupiter and Saturn have been appearing close together in the evening sky all through the summer
and fall. In December in the southwestern dusk, the angle between them shrinks until they merge into one point on
December 21. You will need binoculars to separate them. In January 2021, the two planets will be lost in the sun’s glare.
I am making available my 2021 Night Sky Highlights, a 2 page document describing the position of the sun, when the
moon can be seen in the evening sky, the dusk and evening times to see the bright planets and the times of sunrise and
sunset for each 2021 Sunday in Oakland and surroundings. Request a free copy from