Archive for December 9, 2020

12/09/2020 – Ephemeris – A look at the naked-eye planets for this week

December 9, 2020 Comments off

This is Ephemeris for Wednesday, December 9th. Today the Sun will be up for 8 hours and 53 minutes, setting at 5:02, the earliest sunset, and it will rise tomorrow at 8:09. The Moon, 2 days past last quarter, will rise at 2:55 tomorrow morning.

Let’s look for the naked-eye planets for this week. Jupiter and Saturn are both low in the southwestern sky from 6 to 7 pm. Jupiter is the very bright one. Above and left it by one and a half degrees or three moon widths will be dimmer Saturn. They are slowly closing, so they will cross paths for us on the evening of December 21st and be seen in the same low power telescope field that evening. Jupiter will set first tonight at 8 pm with Saturn following at 8:08. Quite high in the southeast at that hour will be Mars, still in Pisces. Mars’ distance is increasing to 65.3 million miles (105.2 million km) away. It will set at 3:10 tomorrow morning. Brilliant Venus will rise at 5:58 am in the east-southeast as it retreats slowly towards the Sun, but actually it’s heading around behind the Sun.

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


Evening planets animation

The evening planets seen at 6:30 pm or about an hour and a half after sunset December 9, 2020. Animation showing non-annotated sky and then with annotations. Click on the image to enlarge. Created using Stellarium and GIMP.

Venus and the Moon in the morning

Venus and the waning crescent Moon at 6:30 am on December 10, 2020. Created using Stellarium.

Binocular Moon

The waning crescent Moon as it might appear in binoculars or a small telescope at 6:30 am December 10, 2020. Created using Stellarium.

Telescopic planets

The planets as seen in a telescope (north up) with the same magnification for the night of December 9/10, 2020. Times of the display are: Jupiter, Saturn and Mars, 6:30 pm; Venus, 6:30 am. Apparent diameters: Jupiter, 33.85″; Saturn, 15.51″, rings, 36.13″; Mars, 13.18″, and Venus 11.32″. Io is transiting Jupiter and will be generally invisible. 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). 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 9, 2020. The night ends on the left with sunrise on the 10th. I’m afraid that the labels for Jupiter and Saturn will overlap, since the planets are getting very close. Click on the image to enlarge. Created using my LookingUp program.