2022, December 21: Winter Solstice, Antares, Moon, Evening Five Planets


December 21, 2022: The Winter Solstice occurs today at 3:48 p.m. CST. The morning crescent is near Antares.  After sundown, see the five bright planets.

Photo Caption – 2022, September 23: Crescent moon with earthshine.


by Jeffrey L. Hunt

Chicago, Illinois:  Sunrise, 7:15 a.m. CST; Sunset, 4:23 p.m. CST.  Check local sources for sunrise and sunset times for your location.

Today marks the Winter Solstice, when the sun reaches its farthest point south of the celestial equator – an imaginary circle directly above Earth’s equator.  The sun is at coordinate 270° of celestial longitude at 3:48 p.m. CST, beginning the astronomical winter season in the northern hemisphere and summer in the southern hemisphere.  We hope our southern hemisphere readers are enjoying long, warm days and the holidays at the beach.

Today’s sun is in front of Sagittarius, and consequently those stars are not visible.  The sun is overhead at the Tropic of Capricorn – 23.5° south latitude.  The name of this geographic latitude is from when the sun appeared in front of that region of the sky.  Earth wobbles slowly and the equinoxes and solstices slide through the zodiac constellations, making the solstice appear behind Sagittarius today.

Daylight has reached the shortest time interval for the year, nine hours, eight minutes.  Latest sunrise time (7:18 a.m. CST) begins on the 28th and lasts through January 10th.

Jupiter’s Great Red Spot’s transit times, when it is in the center of the planet in the southern hemisphere: 6:07 UT, 16:03 UT, Dec. 22, 1:59 UT. Convert the time to your time zone. In the US, subtract five hours for EST, six hours for CST, and so on.  Use a telescope to see the spot.  Times are from Sky & Telescope magazine.

Chart Caption – 2022, December 21: Mercury appears farthest from the sun this evening – its greatest elongation.

Mercury is at its greatest separation or elongation from the sun today.  The planet appears as far away from the sun as it can get.  Mercury is farthest east of the sun at 9:31 a.m. CST.  This evening, Mercury sets eighty-six minutes after the sun and twenty-five minutes after Venus.

From the accompanying chart as viewed from north of the solar system, the Sun-Earth-Mercury angle is at its largest.  The chart shows Venus at a smaller elongation from the sun, so that it appears lower in the sky than Mercury and closer to the sun.

Here is today’s planet forecast:

Morning Sky

Chart Caption – 2022, December 21: The thin crescent moon is to the upper right of Antares – making its first morning appearance – and to the lower left of Dschubba.

This morning signals the return, heliacal rising, of Antares to the southeastern morning sky before sunrise.  The star was at its solar conjunction on the 1st. At forty-five minutes before sunrise, the star is about 4° up in the southwest.  Depending on the weather, clarity of the sky, and obstructions at the horizon, look for the star first with a binocular, then locate it without the optical assist.

The crescent moon, 5% illuminated, is 5.8° to the upper right of Antares. The pair fit into the same binocular field of view, the moon to the upper right and the star to the lower left.

Dschubba, the Scorpion’s forehead is 1.0° to the upper right of the lunar slice.

Evening Sky

Chart Caption – 2022, December 21: Venus and Mercury are in the southwest after sundown.

The five bright planets are lined up across the sky after sundown. Eastward from the sunset point, the order is Venus, Mercury, Saturn, Jupiter, and Mars.  In terms the brightness, the order:  Venus, Jupiter, Mars, Mercury, and Saturn.

At thirty-five minutes after sundown, the five planets are in the sky, but the sky brightness may washout Saturn.  This depends on the clarity of the sky.

First find a location that provides an open view of the sky from the southwest to the east-northeast.  An elevated structure or hilltop help with the initial views of Venus and Mercury.

Brilliant Venus can be found about 4° up in the southwest.  It is slightly to the north of the southwest direction point.  It is bright enough to be seen without a binocular, but one may help with the initial identification. 

Mercury is 5.5° to the upper left of Venus, appearing to the upper left in a binocular field when Venus is to the lower right.

Chart Caption – 2022, December 21: Jupiter and Saturn are in the southern sky after sundown.

Saturn is about 30° above the south-southwest horizon and over the same distance to the upper left of Mercury.  It stands alone in the sky.  Carefully look for it.  A binocular may help.  Slowly sweep the region while looking through the binocular.  Then look without it.

Jupiter is in the south-southeast, to the upper left of Saturn. It is bright enough to be seen without optical help.

Chart Caption – 2022, December 21: Mars is in the east-northeast with Capella and Aldebaran.

Mars is in the east-northeast, about 20° above the horizon.  The stars Aldebaran and Capella might be visible as well.

This view gets better during the next few evenings.  The moon enters the evening sky on the 24th, appearing with Venus and Mercury.

After greatest elongation, Mercury begins to fade from view, but it can be seen several minutes later during twilight.

Finding this five-planet display is a balance of the sky clarity and the time of the observations.  This evening, begin looking about 30 minutes after sunset.  The five bright planets should be visible before Venus is too low about 15 minutes.  This window advances later each evening.  Sky watchers at more southerly locations see Venus and Mercury higher in the sky.

Jupiter (NASA Photo)

For sky watchers with telescopes, Jupiter’s Great Red Spot is in its prime observing location at 7:59 p.m. CST.  The planet is less than 40° up in the southwest, higher for observers farther westward.

Tomorrow morning, the moon is no longer visible in the morning as it approaches the New moon phase at 4:17 a.m. CST on the 23rd.  By then, the planets have set, appearing again tomorrow evening.



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