2022, May 10: Morning Planet String, Mercury in Disappearing Act


May 10, 2022: The four morning planets – Venus, Jupiter, Mars, and Saturn – are along the eastern horizon before sunup.  Mercury begins to retrograde as it moves toward bright twilight along with winter’s evening stars.

Chart Caption – 2022, May 10: Venus, Jupiter, Mars, and Saturn are strung along the western sky during morning twilight.


by Jeffrey L. Hunt

Chicago, Illinois:  Sunrise, 5:36 a.m. CDT; Sunset, 7:59 p.m. CDT.  Check local sources for sunrise and sunset times for your location.

Morning Sky


Four bright planets – Venus, Jupiter, Mars, and Saturn – are strung across the eastern sky before sunrise.  They span over 44° from Venus to Saturn. 

At forty-five minutes before sunrise, the Morning Star is over 8° above the east horizon.  Saturn is over 23° up in the southeast.  Bright Jupiter and Mars are between them.

Brilliant Venus shines as the “brightest star” in the sky.  Its cloud tops reflect 75% of the sunlight that falls on them.  This morning the planet is over 99 million miles away.

Bright Jupiter is 9.0° to the upper right of Venus.  This slower-moving planet cannot keep up with the quick-stepping Venus.  Jupiter is over five times farther away than Venus this morning.  The Jovian Giant reflects 34% of the sunlight that reaches its upper clouds, but it only receives less than 1% of the sunlight that reaches Venus.

Jupiter is very large, over 1,300 planets the size of Venus could fit into an empty giant planet.  The size of the planet and its reflectivity make it the second brightest “star” in the sky, even brighter than Sirius, the brightest actual star in the night sky.

Mars, marching eastward toward Jupiter, is 10.8° to the upper right of the Jovian Giant this morning.  The Red Planet is over 146 million miles away.  It is about half the diameter of Earth and reflects only 25% of the sunlight that reaches its surface.

The Red Planet brightens when near Earth and at times it outshines Jupiter.  Earth passes Mars during December.  Between now and then, its brightness grows weekly.

Saturn is over nine times farther away than Venus.  It has about the same reflectivity as Jupiter, but at nearly double Jupiter’s solar distance, the Ringed Wonder receives about one-fourth of the sunlight of Jupiter.  This morning it is slightly dimmer than Mars.

Watch the changing gaps between the planets as Venus steps farther eastward and Mars approaches Jupiter for a conjunction at month’s end.

Evening Sky

Chart Caption – 2022, May 10: The bright moon is high in the south below Leo’s brighter stars.

The bright moon, 70% illuminated, is high in the south as night falls.  It is below Leo’s main star pattern of the sickle and triangle.  The lunar orb is 14.8° to the lower left of Regulus, meaning “the prince,” and 10.7° to the lower right of Denebola, “the lion’s tail.”

Lunar Eclipse (NASA Photo)

The moon passes into Earth’s shadow in five evenings for sky watchers across the western hemisphere.  The best part of the eclipse show lasts nearly 90 minutes, reaching the mid-point at 11:11 p.m. CDT.

Chart Caption – 2022, May 10: Mercury and the bright stars of winter are receding into bright twilight.

Mercury begins to retrograde, move westward compared to the stars.  It is receding into bright twilight, moving toward its inferior conjunction between Earth and the sun.

The planet has dimmed considerably.  It is only about 6° up in the west-northwest at 45 minutes after sundown.  Just outside Mercury’s binocular field, the star Aldebaran is 8.8° to the left of the speedy planet.

Scan the western horizon.  Likely, Sirius is twinkling wildly from its spot low in the west-southwestern sky.  It is nearly its last evening appearance before disappearing into bright twilight.  It seems to pass behind the sun and reappears in the southeastern sky later during the summer.  What is the last day that you see the Dog Star?

Orion’s Betelgeuse is nearly 15° up in the western sky.  Watch it appear lower in the sky each evening, what is the last night that you see it?



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