2022, July 21: Martian Winter, Morning Planet Parade


July 21, 2022: Winter begins in the Martian northern hemisphere today. Before sunrise, the thick lunar crescent is near Mars in the morning planet parade of four planets and the lunar orb.

Photo Caption – 2007, December 1: Late winter in the northern hemisphere shows clouds above the northern polar cap and some above the southern cap. (NASA Photo)


by Jeffrey L. Hunt

Chicago, Illinois:  Sunrise, 5:34 a.m. CDT; Sunset, 8:20 p.m. CDT.  Check local sources for sunrise and sunset times for your location.

Winter begins in the Martian northern hemisphere today.  The planet is tilted over 25° with respect to its orbital plane, and its day (or sol) is 39 minutes longer than Earth’s day.  The seasonal changes are noted in the atmosphere and surface conditions.  Growing and shrinking polar caps, clouds, dust storms, and seasonal changes on the planet’s surfaces from blowing dust influenced telescopic sky watchers to consider that Mars might be like Earth and have life – Martians.  Robot spacecraft continue to look for even the simplest forms of life on the nearby world.  Winter lasts until December 26, 157 days.  In comparison, Earth’s northern hemisphere winter begins December 21, 2022 and lasts until March 20, 2023, 89 days.

Here is today’s planet forecast.

Morning Sky


One hour before sunrise, the thick crescent moon, 42% illuminated, is about halfway up in the east-southeast, 2.9° to the upper right of Mars.  The planet is dimmer.  Look carefully to find it because of the moon’s brightness.

Later today, the moon covers the Red Planet for sky watchers in eastern Asia, Alaska, and Greenland

Mars is marching eastward in Aries and generally toward the Pleiades star cluster that is in the boundaries of Taurus.  The Red Planet passes the star cluster in about a month.

Aries’ brightest star is Hamal that is about the brightness as the stars in the Big Dipper.  The star is over 12° above Mars this morning.

Bright Jupiter, slightly higher than the moon, is in the east-southeast.  The Jovian Giant is in front of the distant stars of Cetus and beginning to slow down before it seems to reverse its direction.  Retrograde motion is an illusion from our faster-moving planet catching and passing between the planet and the sun.

Hold a binocular steadily to spot Callisto, one of Jupiter’s four largest moons, appear as a dim star on the west side of the planet. It is near its maximum distance from the planet this morning.  A spotting scope or telescope reveals more moons.

Chart Caption – 2022, July 21: Venus, low in the east-northeast, passes Castor’s foot.

Looking farther eastward, brilliant Venus is about 9° up in the east-northeast.  It is quickly stepping eastward in Gemini, near the foot of Castor.  A pair of stars, known as Propus (toe) and Tejat Posterior (heel), appear near the planet. A binocular may be needed to see them.  Venus is below Elnath and Zeta Tauri (ζ Tau on the chart), the Bull’s horns.

Chart Caption – 2022, July 21: Saturn retrogrades in Capricornus. Find it in the south-southwest before sunup.

The fourth morning planet is Saturn.  It is in the south-southwest, retrograding in eastern Capricornus, near the stars Deneb Algedi and Nashira.

Chart Caption – 2022, July 21: Through a binocular, Saturn is near Deneb Algedi and Nashira.

Look at the starfield with a binocular. Along with Deneb Algedi and Nashira, three stars, cataloged as 42 Capricorni (42 Cap on the chart), 44 Capricorni (44 Cap), and 45 Capricorni (45 Cap), appear in the same field of view.  Watch Saturn move past the dimmer trio and then make an isosceles triangle with the two named stars at month’s end.

Mercury, the fifth bright planet, is not easily seen. It passed behind the sun five days ago and it is setting about 25 minutes after sunset.  At its best next month, the speedy sets less than an hour after the sun, a challenging observation to make.

Evening Sky

Chart Caption – 2022, July 21: Saturn is the first bright planet to appear in the eastern sky after sundown.

Saturn is becoming visible after sunset, rising about 70 minutes after sundown.  Wait longer to see it higher in the southeast.  Jupiter rises nearly 50 minutes after Saturn, while Mars rises nearly 80 minutes later than the Jovian Giant.  At nearly 1 a.m. CDT in Chicago, Moonrise occurs only 15 minutes after Mars rises. By morning twilight, Venus rises with the four planets and the moon strung across the sky from east-northeast to south-southwest.



Leave a Reply Cancel reply