2021, May 11: Planets March On

May 11, 2021: The planet parade continues today. Five planets are on display.  Bright Jupiter and Saturn are in the southeastern sky before sunrise.  After sundown, brilliant Venus, Mercury, and Mars are in the western sky.  The moon is at its New phase and at apogee today.

2021, May 11: Jupiter and Saturn are in the southeast before sunrise.
Chart Caption – 2021, May 11: Jupiter and Saturn are in the southeast before sunrise.

by Jeffrey L. Hunt

Chicago, Illinois:  Sunrise, 5:35 a.m. CDT; Sunset, 8:00 p.m. CDT.  Check local sources for sunrise and sunset times for your location.

The sun sets at 8 p.m. CDT and sets later than this time for nearly the next 90 evenings.

Morning Sky

The morning planet parade begins nearly 4 hours before sunrise, when Saturn makes its first appearance in the southeastern sky.  Bright Jupiter follows about 45 minutes later.

By an hour before sunup, Saturn is over 24° above the south-southeast horizon.  The Ringed Wonder is brighter than most of the stars in the sky, except for Jupiter.

Saturn is slowly moving eastward in Capricornus, just a few days before the beginning of the illusion of retrograde motion.

The outer planets seem to move westward compared to the distant stars as Earth catches up to and passes between them and the sun.

This morning, use a binocular to see the dimmer starfields that are behind the planets.  Saturn is 0.7° to the right of the star Theta Capricorni (θ Cap on the chart).

Jupiter is over 16° to the lower left of Saturn and 1.4° to the upper left of Iota Aquarii (ι Aqr).

The planet parade is interrupted by the sun’s appearance in the sky.  Saturn and Jupiter lead the way and set before sundown.  Venus, Mercury, and Mars rise during the daytime, following the glowing solar disk across the sky, becoming visible after sunset.

The moon has not been visible in the planet parade during the last two days and nights.  It has been near its New moon phase, when its nearside is in darkness.  The moon is New at 2 p.m. CDT.

During the moon’s monthly tour of the constellations, it reaches its farthest point from Earth (apogee, 252, 582 miles) at 4:53 p.m. CDT.

Evening Sky

2021, May 11: Thirty minutes after sunset, Venus is 5.0° above the west-northwest horizon. Mercury is 9.1° to the upper left of Venus.
Chart Caption – 2021, May 11: Thirty minutes after sunset, Venus is 5.0° above the west-northwest horizon. Mercury is 9.1° to the upper left of Venus.

After today’s New moon phase, the razor-thin moon appears with Venus tomorrow evening.

This evening, Venus is the first planet to emerge from the sun’s glare.  Look for it 5.0° above the west-northwest horizon at 30 minutes after sunset.  A binocular may be needed to initially locate the earth’s nearest planetary neighbor.

Mercury – bright, but dimmer than yesterday – is 9.1° to the upper left of Venus.  Both planets do not fit into a single binocular field.  Find Venus and move the binocular a little to the upper left.  Mercury is then visible.

Venus as an evening star article.

Read more about Venus in our summary document.

2021, May 11: Forty-five minutes after sunset, three planets are visible: Venus, Mercury, and Mars.
2021, May 11: Forty-five minutes after sunset, three planets are visible: Venus, Mercury, and Mars.

By 45 minutes after sunset, Venus is a few degrees above the horizon.  It is bright enough to be seen at this altitude if the horizon is clear of obstructions (and clouds).  Mercury is easily visible 11.0° above the horizon.  Mars – over one-third of the way up in the west – is nearly 29° to the upper left of Mercury.

Here’s more about Mercury during May 2021.

2021, May 11: One hour after sunset, Mars is 1.2° to the upper left of Epsilon Geminorum (ε Gem) and 5.2° to the lower right of and Zeta Geminorum (ζ Gem).
Chart Caption – 2021, May 11: One hour after sunset, Mars is 1.2° to the upper left of Epsilon Geminorum (ε Gem) and 5.2° to the lower right of and Zeta Geminorum (ζ Gem).

An hour after sunset, Venus is setting.  Mercury follows less than an hour later. 

Mars is still about one-third of the way up in the west.  It is marching eastward in Gemini, under Castor and Pollux.  The plane of the solar system, runs diagonally across Gemini from the lower right of the chart to the upper left corner.  Mars ends the month to the lower left of Pollux.

This evening the planet is 1.2° to the upper left of Mebsuta (ε Gem on the chart), “the outstretched paw of the lion,” and 5.2° to the lower right of Mekbuda (ζ Gem), “the folded paw of the lion.”

Tonight. Mars sets 4 hours after sunset.  The parade begins again when Saturn rises over 90 minutes after Mars sets.

Here’s more about Mars during 2021.

Detailed Note: Jupiter and Saturn continue their slow dance with the starry background before sunrise.  One hour before sunup, Saturn is over 24° above the south-southeast horizon and 0.7° to the right of θ Cap.  Bright Jupiter is 16.3° to the lower left of Saturn and 1.4° to the upper left of ι Aqr.  The moon is at its New phase at 2 p.m. CDT.  At 4:53 p.m. CDT, the moon is at apogee, 252,582 miles away.  Thirty minutes after sunset, Venus is 5.0° above the west-northwest horizon.  Use a binocular to locate Mercury (m = −0.2), 9.1° to the upper left of Venus.  Fifteen minutes later, Venus is 2.5° above the horizon; Mercury is 11.0° above the west-northwest horizon; and Mars is nearly 34° up in the west.  One hour after sunset, Mercury is still over 8° above the west-northwest horizon.  Mars is nearly 29° to the upper left of Mercury.  In the starfield, use a binocular to spot ε Gem 1.2° to the lower right of the Red Planet and Zeta Geminorum (Mekbuda, ζ Gem, m = 4.0) 5.2° to the upper left of the planet. Mars sets four hours after sunset.

Read more about the planets during May 2021.



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