December 23, 2022: See a rare display of the five bright planets – Venus, Mercury, Saturn, Jupiter, and Mars – simultaneously after sunset.
by Jeffrey L. Hunt
Chicago, Illinois: Sunrise, 7:16 a.m. CST; Sunset, 4:24 p.m. CST. Check local sources for sunrise and sunset times for your location.
Daylight has reached the shortest time interval for the year, nine hours, eight minutes. Latest sunrise time (7:18 am 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: 7:46 UT, 17:42 UT; December 24, 3:38 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 pious Sky & Telescope magazine.
Here is today’s planet forecast:
The morning sky is without a bright planet. Tomorrow morning at 4:17 am CST, the moon begins lunation 1237. The lunation is the number of lunar cycles since 1923.
Step outside about an hour before sunrise and look towards the southwest. Leo, with its bright star Regulus, is over halfway up in the sky. The constellation is featured here each month when the moon passes these stars.
This morning’s interest is the Big Dipper that is high in the northern sky. Notice on the chart the overhead mark, sometimes called the zenith – the highest spot in the sky.
When the dipper is high in the sky as it is during late autumn and early winter mornings, it helps us locate other stars. Its pointer stars at the end of the bowl direct us to Polaris, the North Star.
Polaris is nearby above Earth’s North Pole. At the geographic North Pole, Polaris is nearly overhead. As such, it does not seem to move much during the night. For casual observing it is north. From mid-northern latitudes, it is about halfway up in the sky. It is not the brightest star, but number 48 on the list of the brightest stars visible in the skies of Earth. The star is not visible south of Earth’s equator.
The curved handle points in the direction of Arcturus that is high in the southeast.
Leo is in the opposite direction from Polaris. It can be found by going through the bottom of the dipper’s bowl.
While there are no planets in the morning sky until late January, several bright stars decorate the celestial vault before sunrise.
During the next five evenings, look for a rare display of the five bright planets, from the sunset point – Venus, Mercury, Saturn, Jupiter and Mars. The next time five planets are in the sky simultaneously is mid-April of 2036.
First, find an open spot that has a clear horizon in the southwest. A hilltop or elevated structure may help to see Mercury and Venus near the horizon.
Second, take binoculars. This is helpful to find Mercury and Venus, and possibly Saturn during brighter twilight.
The observing window is narrow, lasting no more than 30 minutes before Venus is too low to see. Begin looking for Venus and Mercury near the southwest horizon about 30 minutes after sunset.
At this time, Venus is nearly 5° above the southwest horizon and to the right of the southwest direction. Venus is far enough from the sun to be seen without binoculars, but use it to initially find the planet.
Mercury is 4.6° to the upper left of the Evening Star and in the same binocular field when Venus is moved to the lower right part of the view.
Try to find Jupiter about halfway up in the south-southeast and Mars in the east-northeast. At this level of twilight, Saturn is not likely to be visible.
The clarity of the atmosphere is a factor. High cirrus clouds or local clouds can make this view a challenge. Sometimes Jupiter and Mars can be seen at this time interval.
Continue to look for the planets during the next 25 to 30 minutes. By 40 minutes after sunset, Venus is lower in the sky with Mercury at the same distance as before.
Saturn is about 30° up in the south-southwest – that’s about one-third of the way from the horizon to overhead. It is the same distance to the upper left of Mercury.
Jupiter is in the south-southeast – halfway up in the sky – and Mars is about 20° above the east-northeast horizon. Capella and Aldebaran are visible near Mars.
Look for the five planets along an arc from Venus to Mars. Do not confuse Saturn with the star Fomalhaut that is lower in the sky and almost above the south direction.
Tomorrow evening, the crescent moon joins Venus and Mercury in the southwest. Two evenings later, the waxing moon is near Saturn. That will help with the identification. Meanwhile, Mercury is still near Venus, but it is beginning to fade in brightness.
Two hours after sunset, look at Saturn through the binoculars to check its eastward direction compared to Deneb Algedi and Nashira. The Ringed Wonder is 1.4° to the upper right of Nashira. The planet passes the star on the evenings of the 27th and 28th.
At 9:38 pm CST, Jupiter’s Great Red Spot is in its prime observing location on the planet, but from Chicago, the planet is only 20° above the west-southwest horizon, not an ideal spot. Sky watchers with telescopes farther westward can see the planet higher in the sky and in clearer air.