Archive

Archive for January 17, 2025

Ephemeris: 01/17/2025 – Venus passes Saturn in conjunction tomorrow

January 17, 2025 Comments off

We end this week of planetary events with this post:

This is Ephemeris for Friday, January 17th. Today the Sun will be up for 9 hours and 16 minutes, setting at 5:31, and it will rise tomorrow at 8:14. The Moon, halfway from full to last quarter, will rise at 9:44 this evening.

Venus will pass the slower moving Saturn at about 11:00 tomorrow morning, so tonight and Saturday night are your best times to see these two planets at their closest. They will probably be slightly closer tomorrow night than tonight. This apparent meeting of two planets is called a conjunction. The two planets are not anywhere close to each other, in fact Venus is closer than the Sun right now, and Saturn is 10 times farther away than the Sun. They just happen to be near the same line of sight. From there both will lose their battle with evening twilight. Saturn will make it back to conjunction with the Sun first, ten days before Venus. Before that Mercury will pass in conjunction with Venus.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

Saturn and Venus are seen on three evenings around 6:30 PM: January 17th, 18th, and 19th
Saturn and Venus are seen on three evenings around 6:30 PM: January 17th, 18th, and 19th. The step is the sidereal day, not the solar day, so the stars would not move, and the motion shown is actually the planets motion against the stars. The sidereal day is 3 minutes 56 seconds shorter than the 24 hour day we call a solar day. Which means the stars set earlier by that amount each night. Created using Stellarium and GIMP.
An oblique perspective view of the solar system showing the line of sight from Earth to Venus and Saturn for the conjunction of January 18th 2025
An oblique perspective view of the solar system showing the line of sight from Earth to Venus and Saturn for the conjunction of January 18th 2025. Created using my LookingUp app , LibreOffice Draw, and GIMP.

Categories: Conjunction, Ephemeris Program, Naked-eye planets, Observing Tags: ,