Bob Moler's Ephemeris Blog

Ephemeris for Wednesday, March 21st. The Sun will rise at 7:44. It’ll be up for 12 hours and 12 minutes, setting at 7:56. The Moon, 3 days before first quarter, will set at 12:39 tomorrow morning.

Let’s take our weekly look at the bright planets. All 5 of the naked eye planets are visible now. Two of them are in the evening sky, but very close to the Sun. Venus will be visible low in the Western twilight from about 8:10 p.m. until before it sets at 9:26. Mercury is much dimmer but at the same height and to the right of Venus, tonight by about 8 Moon widths. Mercury is dimming rapidly. In the morning Jupiter will rise at 12:20. Mars will rise at 3:33. Saturn will end the procession, rising at 3:53 a.m. At 7 tomorrow morning these three planets will be strung across the southern sky. Bright Jupiter will be in the southwest, dimmer Mars will be in the south. Saturn will be in the south-southeast.

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

Addendum

The morning planets of Jupiter, Mars and Saturn seen at 7 a.m. EDT this morning March 21, 2018. Click on image to enlarge. Created using Stellarium.

Jupiter and Saturn with their brighter satellites this morning at 7 a.m. March 21, 2018. They are displayed at the same scale. Saturn in about twice as far as Jupiter. Its disk is a bit smaller than Jupiter’s so it appears about half as large. The extent of the rings appear to be about the same as Jupiter’s diameter. Created using Cartes du Ciel (Sky Charts).

Jovian satellite events this morning

Satellite Event              Date       Universal  Local Time 
Ganymede: Eclipse start:     21 Mar 2018  7:30 UT  3:30 am EDT
Io      : Shadow start:      21 Mar 2018  8:08 UT  4:08 am EDT
Io      : Transit start:     21 Mar 2018  9:09 UT  5:09 am EDT
Ganymede: Eclipse end :      21 Mar 2018  9:15 UT  5:15 am EDT
Io      : Shadow end :       21 Mar 2018 10:18 UT  6:18 am EDT
Io      : Transit end :      21 Mar 2018 11:17 UT  7:17 am EDT
Ganymede: Occultation start: 21 Mar 2018 11:50 UT  Not visible
Ganymede: Occultation end :  21 Mar 2018 12:54 UT  Not visible

An eclipse is when the moon passes through Jupiter’s shadow.
An occultation is when the moon is hidden behind the planet.
Shadow denotes the projection of a satellite’s shadow on the face of Jupiter.
Transit is the passage of a satellite across the face of Jupiter.  It becomes hard to find against the.

Timings are from https://www.projectpluto.com.

Venus and Mercury, low in the west at 8:30 p.m., March 21, 2018. Created using Stellarium.

The waxing crescent Moon as it might be seen in binoculars at 9 p.m. tonight. March 21, 2018. Created using Stellarium.

Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on March 21, 2018. The night ends on the left with sunrise on the 22nd. Click on the image to enlarge. Created using my LookingUp program.