Archive for December 23, 2020

12/23/2020 – Ephemeris – Let’s look for the naked-eye planets for this Christmas week

December 23, 2020 Comments off

This is Ephemeris for Wednesday, December 23rd. Today the Sun will be up for 8 hours and 48 minutes, setting at 5:06, and it will rise tomorrow at 8:18. The Moon, 2 days past first quarter, will set at 2:49 tomorrow morning.

Let’s look for the naked-eye planets for this week. Jupiter and Saturn are both low in the southwestern sky around 6 pm. Jupiter is the very bright one. Below and right of it is the dimmer Saturn it by a quarter of a degree or half a moon width. They crossed paths for us two nights ago, in 20 years, though not as close. They can still be seen in the same low power telescope field. Saturn will now set first tonight at 7:20 pm with Jupiter following a minute later. Quite high in the southeast and above the 9 day old Moon at that hour will be Mars, still in Pisces. Mars’ distance is increasing to 76 million miles (123 million km) away. It will set at 2:41 tomorrow morning. Brilliant Venus will rise at 6:33 am in the east-southeast as it seems to retreat slowly toward the Sun, but actually it’s heading way around behind the Sun.

The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.


Jupiter and Saturn in the twilight

Jupiter and Saturn in twilight at 6 pm or a bit less than an hour after sunset tonight December 23, 2020. Created using Stellarium.

Mars above the Moon

Mars will be seen above the Moon tonight. This is the appearance of both at 6 pm, tonight, December 23, 2020. Created using Stellarium.

Binocular Moon

The gibbous Moon as it might be seen in binoculars this evening at 6 pm December 23, 2020. Created using Stellarium.

Venus in the morning twilight

Venus low in the southeast at 7:30 am December 24, 2020. The morning sky is not as friendly to morning planets as it was earlier in autumn. Created using Stellarium.

Telescopic planets

The planets as seen in a telescope (north up) with the same magnification for the night of December 23/24, 2020. Times of the display are: Jupiter, Saturn, and Mars, 6 pm; Venus, 7:30 am. Apparent diameters: Jupiter, 33.18″; Saturn, 15.32″, rings, 35.70″; Mars, 11.32″, and Venus 10.89″. Mars also displays an enlargement showing surface detail. Mars was closest to the Earth this go-a-round on October 6. The ” symbol means seconds of arc (1/3600th of a degree.) I will no longer show planets whose diameters drop below 10″, or are too close to the direction of the Sun to observe. Created using Cartes du Ciel (Sky Charts).

Planets and the Moon on a single night

Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on December 23, 2020. The night ends on the left with sunrise on the 24th. I’m afraid that the labels for Jupiter and Saturn will overlap, since the planets are very close. Click on the image to enlarge. Created using my LookingUp program.