2020, August 4: About 70 minutes after sunset, Jupiter is 0.8° to the lower right of 50 Sagittarii (50 Sgr) and 3.6° to the lower left of Pi Sagittarii (π Sgr). Meanwhile, Saturn is 2.8° to the lower left of 56 Sagittarii (56 Sgr).
Look for bright Jupiter and Saturn in the southeast during the hours following sunset.
by Jeffrey L. Hunt
Jupiter and Saturn are low in the southeastern sky during the hours following sunset. They appear as overly bright stars. Jupiter is to the upper right of dimmer Saturn. This evening they are 7.8° apart. The pair continues to retrograde in eastern Sagittarius as the gap between them grows.
Retrograde is an illusion that appears when Earth overtakes, passes, and moves away from planets that revolve around the sun farther from our central star than our home planet. Normally, planets appear to move eastward when compared to the starry background. While they rise in the east and set in the west during a 24-hour period from Earth’s rotation, these planets seem to move eastward compared to the stars. This occurs because of the mutual revolution of Earth and the planets around the sun.
Earth passed Jupiter on July 13 and Saturn a week later. This giant planet duo retrogrades until next month. When they resume their eastward motion, Jupiter overtakes and passes Saturn on December 21, 2020 in what is known as a Great Conjunction.
Jupiter revolves around the sun in 11.8 years and Saturn in 29.5 years. Jupiter overtakes and passes Saturn in our sky every 19.6 years. While the great conjunction is not rare, it occurs at intervals of once every generation. This year’s conjunction is the closest passing of the two planets since 1623.
Each night at the same hour Jupiter and Saturn are farther westward in the sky. The December conjunction occurs in the southwest sky.
If you’re up early enough tomorrow morning, catch Jupiter and Saturn before they set at 4 a.m. At that hour bright Mars is in the southeast and brilliant Venus is in the east.
Here is a daily summary about the planets during August.
Venus, Mars, Saturn, and Jupiter shine from the morning sky. The morning planet parade breaks apart.
by Jeffrey L. Hunt
About two hours before sunrise, brilliant Venus gleams from the eastern sky. It is near the Southern Horn of Taurus the Bull, known as Zeta Tauri (ζ Tau on the photo).
For over a month, Venus has been moving eastward in Taurus. Tomorrow, Venus moves into the club region of Orion. Bellatrix, a shoulder of Orion, is visible in the photo above.
2020, August 4: Shining from the dim stars of Pisces, Mars is is 0.3° to the upper left of 89 Piscium (89 Psc on the photo) and 3.7° to the lower right of Zeta Piscium (ζ Psc).
About an hour earlier, with a bright moon in the sky and only four hours past its official Full phase, Mars shines from the dim starfield of Pisces. It continues to march eastward along the solar system’s plane. Use a binocular to track Mars through the starfield, especially with the bright moon in the sky for the next several mornings.
Next month, the Red Planet starts to retrograde. Mars appears to move westward compared to the stars. On October 13, 2020, Earth passes between the planet and the sun. Mars and the sun are in opposite directions from Earth. This is known as opposition. The planet rises in the east at sunset and sets in the west at sunrise. Around opposition, Mars is closest to Earth and appears at its brightest. This occurs a week before opposition.
This morning Mars is 0.3° to the upper left of 89 Piscium (89 Psc on the photo) and 3.7° to the lower right of Zeta Piscium (ζ Psc).
2020, August 4: Appearing low in the southwest, Jupiter and Saturn are disappearing from the early morning sky. This morning, Saturn is 7.8° to the upper left of Jupiter.
Jupiter and Saturn are appearing very low in the sky at this hour. Better views occur when the planets are in the evening sky. Ninety minutes after sunset, they are shining from low in the southeastern sky,
Both planets are retrograding in eastern Sagittarius. They reverse their courses next month. As the year closes, Jupiter passes Saturn on December 21, 2020, in a Great Conjunction.
Here is a daily summary about the planets during August.
(In the image above, 2020, July 17: The crescent moon, Brilliant Venus, and Aldebaran shine from the eastern during early morning twilight.)
Venus and the moon make a spectacular scene before sunrise on August 15. Artists and photographers can create inspiring interpretations of the view.
by Jeffrey L. Hunt
Venus sparkles in the eastern sky before sunrise during the summer and autumn months. During the moon’s monthly journey, it moves past this brilliant planet. During August, the moon makes a close pass with Venus, creating the inspiring scene. From North America, the thin lunar crescent, that is about 15% illuminated, is 3.6° to the upper left of the brilliant planet.
August 15: The crescent moon is 3.5° to the upper left of Venus.
At mid-northern latitudes on August 15, Venus rises over three hours before sunrise. By an hour later, the Venus – Moon pair is over 15° in altitude in the eastern sky. Early risers may have to find a spot away from trees, houses, and other obstructions to see Venus and the moon in the eastern sky.
As the morning progresses and the sky brightens, Venus and the moon rise higher in the sky.
2020, July 17: The crescent moon, Venus, and Aldebaran in the eastern sky before sunrise.
Each stage of morning twilight presents spectacular views of the celestial pair shining in the eastern sky and varying opportunities to capture the view with a camera.
The pair can be photographed with cameras that have time exposure settings. Exposures can range from fractions of a second through a few seconds. By varying the exposure times, a suitable image can be captured.
The longer the exposure, the more the moon’s nighttime side appears in the photo. This gentle illumination known as “Earthshine,” is from sunlight reflected from Earth’s clouds, continents, and oceans. It softly illuminates the night portion of the moon.
2020, July 14: The moon is in the eastern sky. It is 23.4 days past its New phase and 37% illuminated. It is a thick waning crescent phase.
At some lunar phases the sunlight reflected from the moon illuminates Earth’s terrestrial features. This is bright enough to create shadows on the ground.
The moon and Venus may be visible after sunrise and well into the morning.
Coincidentally, the Venus – Moon grouping occurs at the same time that Sirius is making its first appearance in the morning sky before sunrise. About 45 minutes before sunrise, Sirius is above the horizon in the east-southeast.
On September 14, the moon passes Venus again, but the moon is farther away and the pair is lower in the sky.
The August 15 grouping of Venus and the crescent moon is the best grouping during Venus’ current appearance in the morning sky, because the two are visible together for over 3 hours before sunrise.
2020, July 28: Jupiter is 0.6° to the left of 50 Sagittarii (50 Sgr), while Saturn is 3.3° to the upper left of 56 Sagittarii (56 Sgr).
Jupiter and Saturn lead Mars and Venus during late July’s morning planet parade.
by Jeffrey L. Hunt
Four planets – Jupiter, Saturn, Mars, and Venus – are strung along an arc in the morning sky. They appear along the solar system’s plane that astronomers call the ecliptic. During the pre-sunrise hours of late July, the imaginary line stretches from the southwest skyline to the east-northeast horizon.
Bright Jupiter and Saturn are low in the southwest in front of the stars of eastern Sagittarius. They are moving westward – retrograding – compared to the starry background. While they rise in the east before sunset and appear low in the southeast during evening hours from Earth’s rotation, they are moving westward compared to the distant stars. This westward movement compared to the stars is an illusion when Earth overtakes, passes, and moves away from them.
Jupiter and Saturn are 7.5° apart. In another month, they are about another degree apart.
In September, Jupiter and Saturn begin moving eastward again. Jupiter inches toward Saturn and passes it in a Great Conjunction, December 21, 2020. This is the closest conjunction of the two planets since 1623. A Jupiter – Saturn conjunction occurs every 19.6 years.
Through a binocular check their positions each clear morning compared to the stars. Jupiter is 0.6° to the left of 50 Sagittarii (50 Sgr), while Saturn is 3.3° to the upper left of 56 Sagittarii (56 Sgr). Watch Jupiter pass 50 Sgr and Saturn approach 56 Sgr.
2020, July 28: Mars is 5.1° to the upper left of 20 Ceti (20 Cet) and 5.0° below Epsilon Piscium (ε Psc).
Farther east, Mars is that “bright star” in the southeast. It is among the dim stars of Pisces. On the photo above, it is moving into the starfield where it retrogrades and passes opposition (October 13, 2020). This morning the Red Planet is 5.1° to the upper left of 20 Ceti (20 Cet) and 5.0° below Epsilon Piscium (ε Psc). As with Jupiter and Saturn, watch Mars move eastward in the starfield through a binocular.
2020, July 28: Venus, in the constellation Taurus, is 4.3° to the upper right of Zeta Tauri (ζ Tau), the Southern Horn of the Bull.
The brilliant Morning Star Venus is in the eastern sky. It is moving eastward among the stars of Taurus. This morning it is 4.3° to the upper right of Zeta Tauri (ζ Tau), the Southern Horn of the Bull. The bright star Aldebaran, the Bull’s Eye, and two star clusters (Hyades and Pleiades) appear above the bright planet.
Here are two daily summaries about the planets during July and August.
2020, July 26: Bright Jupiter and Saturn are in the southwest during morning hours, they are 7.3° apart. Jupiter is 0.7° to the left of 50 Sagittarii (50 Sgr). Saturn is 3.4° to the upper left of 56 Sagittarii (56 Sgr). Jupiter’s moon Ganymede is visible.
Four bright morning planets – Venus, Mars, Saturn, and Jupiter – span the sky.
by Jeffrey L. Hunt
Four bright planets – Venus, Mars, Saturn, and Jupiter – span the morning sky from the east-northeast horizon to the southwest skyline.
During the predawn hours, bright Jupiter and Saturn are in the southwest. They appear among the stars of eastern Sagittarius. These giant planets are 7.3° apart. Look at Jupiter with a binocular. It’s possible to see some of its four bright Galilean moons, first observed in Galileo’s telescope during the 17th century. This morning Ganymede is visible in the photo above.
Look for Jupiter and Saturn in the southeast about an hour after sunset, as they clear the local trees, houses, and buildings. During the night, they appear to move westward.
2020, July 26: Mars, high in the southeast, is 4.3° to the upper left of 20 Ceti (20 Cet) and 5.3° to the lower right of Epsilon Piscium (ε Psc).
During the morning hours, Mars is high in the southeast, among the stars of Cetus. Tomorrow it moves into Pisces. The stars identified on the accompanying photo show the dim star field where the Red Planet passes opposition, October 13, 2020.
2020, July 26: In Taurus, brilliant Venus is morning eastward toward Zeta Tauri (ζ Tau). This morning Venus is 5.8° to the upper right of the star.
Brilliant Venus is in the eastern sky. It is in front of the stars of Taurus the Bull. Watch it move toward and pass Zeta Tauri (ζ Tau), the Southern Horn of the Bull, on the photo, during the next several mornings. This morning Venus is 5.8° to the upper right of the star.
Notice that Aldebaran and the Hyades star cluster make a sideways “V” that represents the head of the Bull. The Pleiades star cluster is higher in the sky, and is said to be riding on the Bull’s back.
Here are more about the planets during July and August.
2020, July 25: Venus in Taurus. The planet continues to move eastward among the stars. It is moving toward ζ Tau. This morning it is 6.5° to the upper right of ζ Tau and 8.6° to the lower left of Aldebaran.
Brilliant Venus shines brightly this morning among the stars of Taurus the Bull.
by Jeffrey L. Hunt
Brilliant Venus shines from the eastern sky this morning in front of the stars of Taurus the Bull. It appears 8.6° to the lower left of Aldebaran and 6.5° to the upper right of Zeta Tauri (ζ Tau on the photo above), the Southern Horn of Taurus. Venus continues to move eastward during the remainder of July as it nears ζ Tau.
Rosy Aldebaran and the Hyades star cluster form a sideways “V” to represent the head of the Bull to the upper right of Venus The single bright star represents the creature’s eye. Aldebaran is about 125 times brighter than the sun and 40 times our central star’s diameter.
The Hyades is a well-studied “galactic” star cluster; that is, the cluster is part of the plane of the Milky Way galaxy, like the sun and solar system, but unlike the globular clusters that revolve around a galactic halo. The Hyades has over 125 members that are heading in space toward a spot near the star Betelgeuse.
The famous Pleiades star cluster (known to school children as the “Seven Sisters”) is above Aldebaran and the Hyades. To the unaided eye, six or seven stars are visible. Through a binocular, more than a dozen stars can be seen. In the photo above, nearly two dozen stars are visible. Detailed studies count over 200 stars in this cluster.
Astronomers think that stars are formed in clumps, somewhat like bunches of grapes. The mutual gravitational pull of the stars though is too weak to keep the clusters together. Over time, stars escape, decreasing the mutual gravitation attraction.
The Pleiades cluster is thought to be younger than the Hyades. The Pleiades cluster’s bright blue stars have short astronomical lives. The cluster is thought to be about 100 million years old while the Hyades could be six times older.
On these warm clear mornings of summer explore Taurus and its star clusters with a binocular. Each morning, notice the location of Venus within the constellation.
2020, July 24: Mercury and Venus shine from the eastern sky this morning about an hour before sunrise. Mercury is 24° to the lower left of brilliant Venus.
Before sunrise catch the two planets inside Earth’s orbit, Mercury and Venus, the eastern sky.
by Jeffrey L. Hunt
Brilliant Venus and Mercury shine this morning from the eastern sky about an hour before sunrise. These two worlds are part of the morning planet parade that is now breaking up. Mercury, in the east-northeast, and Jupiter, low in the southwest, are near the horizon. Venus, Mars, and Saturn are scattered between the other two naked-eye planets.
2020, July 24: Mercury is low in the east-northeast about one hour before sunrise.
This morning Venus and Mercury are 24° apart. As the images above indicate, locate a clear horizon to find this elusive planet.
2020, July 23: Venus and Mercury shine from the eastern sky during bright morning twilight. Mercury is nearly 24° to the lower left of Venus.
Five planets – Mercury, Venus, Mars, Jupiter, and Saturn – are visible together before the morning planet parade begins to break up.
by Jeffrey L. Hunt
Five planets arch across the clear sky this morning. For the next few mornings during twilight and before Jupiter sets, view five planets that span the sky from the east-northeast skyline to the southwest horizon.
2020, July 23: Jupiter is 7.2° to the lower right of Saturn. Jupiter is 1.0° to the upper left of 50 Sagittarii (50 Sgr, m = 5.6), while Saturn is 4.5° to the lower right of Sigma Capricorni (σ Cap, m = 5.2).
Bright Jupiter and Saturn are in the southwest among the stars of eastern Sagittarius. They are retrograding – moving west – compared to the starry background. This is an illusion as our planet moves away from this giant planet pair. They continue to retrograde until September. This morning the Jupiter – Saturn gap is 7.2°. The planets continue to separate until their retrograde motion ends.
During the fall months, Jupiter inches up and catches the Ringed Wonder on December 21, 2020 for a Great Conjunction. This is the closest conjunction of the two planets since 1623.
Jupiter and Saturn are visible in the southeast as the sky darkens each evening. Use a binocular to watch them continue to move westward compared to the stars identified in the photo above. The stars, with their astronomical names Sigma Capricorni (σ Cap on the photo), 56 Sagittarii (56 Sgr), 50 Sagittarii (50 Sgr) and Pi Sagittarii (π Sgr), make the background to watch the planets. During the next month, the planet pair is lower in the southwestern sky during early morning hours and higher in the eastern sky during evening hours.
In the photo above three of Jupiter’s four largest satellites are visible. They can be seen with a binocular, depending on their positions when they are viewed.
2020, July 23: Mars, in the southeastern sky, moves eastward among the stars of Cetus. It is 3.1° to the upper left of 20 Ceti (20 Cet, m = 4.8). It is moving eastward toward the region of Pisces where its retrograde motion begins.
Mars is farther east, over halfway up in the southeast among the stars of the constellation Cetus. Mars is well passed 20 Ceti (20 Cet on the photo) and heading toward a starfield in Pisces that includes Zeta Piscium (ζ Psc on the photo), 89 Piscium (89 Psc), Mu Piscium (μ Psc), Nu Piscium (ν Psc), and Omicron Piscium (ο Psc).
Mars begins its retrograde motion during early September near the stars on the left side of the starfield in the photo. Use a binocular to watch the Red Planet move toward them during the next few weeks. The planet rises at about 11:30 p.m. local time and its easier to see in the east an hour later.
2020, July 23: Brilliant Venus, among the stars of Taurus, is 7.3° to the lower left of Aldebaran. The Hyades star cluster and Pleiades star cluster appear nearby.
Meanwhile in the eastern sky, brilliant Venus is in Taurus, 7.3° to the lower left of Aldebaran, the constellation’s brightest star. The planet continues moving eastward and away from Aldebaran.
Together, Aldebaran and the Hyades star cluster make a “V” shape, sideways when it is in the eastern sky, to identify the head of the Bull. The Pleiades star cluster, higher in the sky, is riding on the Bull’s back.
Elusive Mercury comes into view as Jupiter is low in the southwest. It is to the lower left of Venus in the brighter glow of morning twilight.
In a few mornings, Jupiter sets before Mercury comes into full view, leaving four planets. Look early enough in the morning to see Jupiter, Saturn, Mars, and Venus. A view later during brighter morning twilight provides a view of Saturn, Mars, Venus, and Mercury.
2020, August 25: Venus and Jupiter are in opposite directions from Earth, a Venus – Jupiter opposition. While not an attraction to view, Jupiter departs from the quartet of bright morning planets. (Planet sizes not to scale.)
Venus and Jupiter appear in opposite directions as viewed from Earth on August 25.
by Jeffrey L. Hunt
Normally, we point to times when Venus passes Jupiter in either the evening or morning sky. Sometimes, Venus appears very close to Jupiter as it passes the solar system’s largest planet. We photograph these conjunctions and display the photographs on these pages.
The Venus – Jupiter opposition is the reverse of a conjunction. The planets are as far apart in the sky as they can appear.
Venus, Mars, Jupiter, and Saturn have stretched across the early morning sky since mid-June. Earth passed Jupiter and the sun on July 14 and Saturn and the sun 6 days later. When a planet, farther away from the sun than Earth, is at opposition, it rises at sunset, appears to move across the sky during the night, and sets at sunrise. Near opposition, the planets are closest to Earth. From their remote places, Earth-based and orbiting telescopes focus on the planet to locate any changes on the surface of the planet.
Now Earth is moving away from Jupiter and Saturn and toward Mars. The Martian opposition is October 13, 2020. Venus passed Earth on June 3 and popped into the morning sky. It is now moving away from us. Venus continues to climb higher into the morning sky. By August 9, Venus reaches its earliest rising time (2:25 a.m. CDT in Chicago, Illinois).
With all these “moving parts,” Venus appears farther away from Jupiter. By mid-August, observing all four planets together in the sky becomes at challenge, even with Venus rising early and observers looking at the sky as early as 3 hours before sunrise.
Earth is between the two planets on August 25, a Venus – Jupiter opposition. Observers are not inclined to view Venus on one horizon and Jupiter on the opposite vista. Yet, it is worth noting that this bright morning quartet of planets is breaking up, much sooner than we wanted, like our favorite music group.
NASA’s Hubble Space Telescope photographed Mars on July 18, 2018, during a dust storm and near its closest approach to Earth since 2003. (NASA photo)
Mars marches eastward among the dim stars of southeastern Pisces during August. It passes perihelion early in the month.
by Jeffrey L. Hunt
Mars is approaching opposition on October 13, 2020. At opposition Mars and the sun are in opposite directions in the sky. As the sun sets in the west, Mars rises in the east. Mars appears in the south around midnight (1 a.m. during daylight time). As morning twilight begins, Mars is low in the western sky, setting before sunrise.
In the sky, Mars appears as an overly-bright star. It is the brightest star in this region of the sky, making its identification easy.
During early August, Mars rises at around 11 p.m., appearing low in the east as midnight approaches. At this time, Jupiter and Saturn are in the south. This giant planet duo starts the evening low in the southeast as the sky darkens.
By early morning, about three hours before sunrise, Mars is part of a quartet of four bright planets that are stretched across the sky from the east to the southwest skyline. Bright Venus is in the east, Mars in the south-southeast, and Saturn and Jupiter in the southwest.
By midmonth, Mars rises about 30 minutes earlier and shines from higher in the eastern sky as midnight approaches. It continues to follow Jupiter and Saturn through the sky.
At this point that the planetary quartet begins to break up. Jupiter disappears below the southwest horizon as Venus climbs into the eastern sky.
By late in the month, when Mars rises around 9:30 p.m. and is well-up in the eastern sky by 11 p.m. By early morning, Jupiter and Saturn have left the sky, as Venus climbs into view.
August 2020: This chart shows the motion of Mars compared to the dimmer stars in southeastern Pisces. During the month, Mars passes near 89 Piscium (89 Psc, m = 5.1), Mu Piscium (μ Psc, m = 4.8), Nu Piscium (ν Psc, m = 4.4) and Omicron Piscium (ο Psc, m = 4.2).
Note that on the accompanying chart, the daily positions of Mars are farther apart than at the end of the month. The planet begins to retrograde next month. Before it reverses course and seems to move westward among the stars, it slows. (A chart in this article shows the retrograde pattern of Mars for this opposition.) The gaps between the daily positions decrease in distance. At the beginning of the month, Mars moves eastward about 0.4° each day. That’s a little less than the apparent size of the moon in the sky. By month’s end, the Red Planet appears to move about half that distance each day.
Because Mars’ orbit is not a perfect circle, Mars is not necessarily closest to the sun or closest to Earth at opposition. Mars is closest to the sun (perihelion) on August 2. Our planet is closest to the Red Planet on October 6, followed by opposition a week later.
Use a binocular to track Mars’ eastward motion in the starfield. Here are dates to note:
August 1: Mars starts the month 1.2° to the upper right of 89 Piscium (89 Psc).
August 2: Mars is closest to the sun (perihelion), 1.38 Astronomical Units from the sun. (An Astronomical Unit – AU – is equal to Earth’s average distance from the sun, about 93 million miles or 150 million kilometers). At this time the Earth – Mars gap is still 0.63 AU. Mars continues to brighten in our sky as we get closer to it.
August 4: Mars passes 0.3° above 89 Psc.
As midnight approaches the moon is 2.1° to the lower right of Mars that is about 13° in altitude in the east.
August 8: Before midnight, look eastward for Mars, 2.1° to the upper left of the gibbous moon that is 73% illuminated. They’ll still be together in the morning.
August 14: The planet is 1.0° to the lower left of Mu Piscium (μ Psc).
August 22: Mars passes 0.5° below Nu Piscium (ν Psc).
August 31: Mars ends the month 2.7° to the lower right of Omicron Piscium (ο Psc).
For more about where to locate the planets in August, here is a semi-technical description of their locations for each day.
