An illustration of the sky showing the moon in close proximity to the sun and Mars in the sky.
(Image credit: Chris Vaughan/Starry Night)
The new moon of December 2023 offers skywatchers dark skies for catching one of the year’s best meteor showers.Â
The new moon of December occurs on Dec. 12, 6:32 p.m. Eastern (2332 UT), according to the U.S. Naval Observatory. Â The young crescent moon will share the sky with the Geminid meteor shower, which is one of the most abundant meteor showers of the year, and two days later the moon will make a close pass to Mercury, making the elusive innermost planet easier to spot.
New moons happen when the moon passes between Earth and the sun, specifically when the sun and moon shares the same celestial longitude as our parent star. A line from north to south from the celestial pole would pass through both. The moon isn’t visible unless there is a solar eclipse, and that means the nights are particularly dark; when meteor showers occur on or near new moons it’s a lot easier to see them as the moon’s light isn’t washing them out.Â
Related: Geminid meteor shower 2023: When, where & how to see it
Geminid meteors
The Geminid meteor shower peaks on Dec. 14, just two days after the new moon, and the waxing crescent moon will set in New York by about 6:00 p.m. An almost-moonless night means seeing the meteor shower will be easier; a bright moon tends to drown them out.Â
The Geminids can produce as many as 150 meteors per hour, according to the American Meteor Society – they are in many respects a winter version of the more famous Perseids. The radiant point (where the meteors seem to come from in the sky) is as the name implies in the constellation Gemini, which in mid-northern latitudes clears the horizon by about 8 p.m. and so is above the horizon almost all night. No moon in the sky means that with clear skies one might see a robust meteor shower, including fainter meteors that otherwise would be impossible to see (provided one is away from city lights).
An illustration of the night sky on Dec. 13, 2023 showing the Geminid meteor shower originating from the Gemini constellation. (Image credit: Chris Vaughan/Starry Night)A young moon passes Mercury
On the same day that the Geminids reach peak activity, our satellite makes a close pass to the planet Mercury, reaching conjunction at 12:20 a.m. EDT on Dec. 14 (0520 GMT). The moon will pass about 4 and one-third degrees south of Mercury; that’s just under nine lunar diameters.Â
For North American observers the moon and Mercury won’t be visible at that point, but in New York they will both be above the horizon by 8:30 a.m. EDT and become just visible as the sky darkens – sunset is at 4:29 p.m.,
