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.
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).
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.
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.
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.
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.
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.
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.
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.
Three bright planets – Jupiter, Mars, and Saturn – shine from the southern skies during the overnight hours.
by Jeffrey L. Hunt
Jupiter and Saturn rise into the southeastern sky as the sky darkens each evening. Mars rises before midnight, and it is higher in the sky after midnight.
By 3 a.m. Jupiter and Saturn are in the southwest and Mars is high in the southeast.
Bright Jupiter and Saturn are near each other, 7.3° apart. In the photo above, Jupiter and Saturn are in eastern Sagittarius. The stars of the distant constellation form the backdrop for the moving planets.
Normally, the planets move eastward compared to the starry background. About each year, our faster moving planet approaches Jupiter and Saturn. These planets appear to stop moving eastward and begin to move westward compared to the stars. This is known as retrograde motion. Earth then passes between Jupiter and the sun, then Saturn and the sun. This is known as opposition. As Earth moves away the planets continue to appear to move backwards, then they start their forward motion again.
For now, Jupiter and Saturn are retrograding, and Jupiter is getting farther from Saturn. By the end of August, Jupiter is about 1° farther away from Saturn than it is this morning. One degree is about the apparent size of two full moons.
Jupiter’s retrograde ends September 12. Even as Jupiter resumes its eastward motion, Saturn continues to retrograde. Saturn’s retrograde ends September 28. Jupiter then closes in on Saturn for a Great Conjunction, December 21, 2020.
Use a binocular to watch the planets move against the stars. This morning Jupiter is 0.9° to the left of the star 50 Sagittarii (50 Sgr on the photo above) and 4.8° to the upper left of Pi Sagittarii (π Sgr). Observe that Jupiter passes 50 Sgr and moves closer to π Sgr during the next month.
Meanwhile, Saturn’s retrograde puts it 3.5° to the upper left of 56 Sagittarii (56 Sgr) and 4.6° to the lower right of Sigma Capricorni (σ Cap). The Ringed Wonder appears to move closer to 56 Sgr and farther from σ Cap during the next month.
Farther east, Mars is marching eastward, over halfway up in the southeast at this hour. The Red Planet is in front of the stars of Cetus. In three mornings, it moves back into Pisces.
About every two years, Earth approaches and passes between the sun and Mars. This year opposition occurs on October 13, 2020. Mars begins to retrograde on September 9, 2020. The planet is moving eastward, but its eastward progress slows in about three weeks.
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). Including Epsilon Piscium (ε Psc) and Delta Piscium (δ Psc), Mars’ motion during the next month is within the dim starfield displayed on the photo.
This morning Mars is 5.6° to the lower right of ε Psc, and 3.6° to the upper left of 20 Cet. Each clear morning, observe Mars’ place among the stars with binocular.
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.
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.
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.
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.
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.
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.
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.
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.
Sparkling Venus shines from the morning eastern sky during August 2020.
by Jeffrey L. Hunt
The brilliant planet Venus shines from the eastern sky during the pre-sunrise hours of August mornings.
The planet is near the Southern Horn of Taurus, Zeta Tauri (ζ Tau), as the month begins.
During eight mornings, the planet moves across the arm and club of Orion, then into Gemini. Use a binocular to track the planet among the Hunter’s dimmer stars. Then Venus moves into Gemini.
Since mid-June, four planets – Venus, Mars, Jupiter, and Saturn – have put on a scintillating morning planet parade. Venus moves rapidly eastward as Jupiter continues to retrograde. On August 1, the Venus – Jupiter gap is 154°. Earth is moving away from Jupiter as Venus moves away from our home planet. This gap continues to widen during August. By mid-month the gap is about 170°. Seeing all four planets together in the sky becomes more difficult without unobstructed, cloud free horizons. On August 25, Earth passes between Venus and Jupiter. This is known as a Venus – Jupiter opposition. It’s not an observable event, except that these four planets are no longer together in the sky. Earth passes between Venus and Saturn during early September.
Here are the highlights for Venus:
(It is important to note that Gemini has many bright stars. Several are highlighted in the following list. Because of the large number in this part of the sky, choose your favorite stars in the region and watch Venus move compared to that starry background.
Venus during August 2020
For those without star charts, the diagram at the top of this article identifies the stars by their astronomical alphabet soup of Greek letters and some proper names. In the notes that follow, the “m” designations are numerical values for star brightness. Like a golf score, the lower values indicate brighter stars. A star of magnitude 1 is 100 times brighter than one of magnitude 6.
August 1 – Venus (V) is 2.1° to the lower right of Zeta Tauri (ζ Tau, m = 3.0).
August 6 – V passes 0.5° to the lower right of Chi1 Orionis (χ1 Ori, m = 4.4).
August 9 – Early in twilight use a binocular to see V 4.5° to the lower right of Messier 35, a star cluster in Gemini. Lower and more difficult to see. This is certainly a stretch, but give it a try. V passes 0.5° below Chi2 Orionis (χ2 Ori, m = 4.6).
August 11 – V passes 2.5° to the lower right of Eta Geminorum (η Gem, m = 3.3).
August 13 – V is 2.4° to the lower right of Mu Geminorum (μ Gem, m = 2.8).
August 15 – The waning crescent moon (25.6 days past New, 16% illuminated) is 3.5° to the upper left of V. V is 0.2° below Nu Geminorum (ν Gem, m = 4.1).
August 17 – V is nearly between Gamma Geminorum (γ Gem, m = 1.9) and Epsilon Geminorum (ε Gem, m = 3.0). Venus passes 3.7° to the upper left of γ Gem.
August 18 – V is 5.0° to the lower right of ε Gem.
August 20 – This morning the planet appears between Castor (α Gem, m =1.6) and γ Gem. The separations are: V – Castor, 15.2° and V – γ Gem, 4.9°.
August 21 – V passes between Pollux (β Gem, m = 1.2) and γ Gem. The brilliant planet is 5.6° to the lower left of γ Gem and nearly 14° to the upper right of Pollux.
August 23 – V is 0.5° to the lower right of Zeta Geminorum (ζ Gem, m = 4.0).
August 25 – V and Jupiter are in opposition.
August 26 – V is 2.2° to the lower right of Delta Geminorum (δ Gem, m = 3.5) and 3.1° to the lower left of ζ Gem. Look carefully with a binocular. Venus is to the right of a line that connects δ Gem and Lambda Geminorum (λ Gem, m = 3.6).
August 27 – V is to the left of a line that connects δ Gem and λ Gem. V is 2.2° to the lower right of δ Gem and 3.4° to the upper left of λ Gem.
August 28 – V is at its maximum rising time interval before sunrise, 222 minutes, as seen from Chicago, Illinois, and other similar latitudes.
August 31 – V passes 8.6° to the lower right of Pollux. The brilliant planet is above a line that starts at Pollux and extends through Kappa Geminorum (κ Gem, m = 3.6) and extends to Procyon (α Cmi, m = 0.4) . The dimmer star is 3.6° to the lower right of Pollux.
For more about the planets this morning, this article provides a semi-technical description of the planetary activity during August.
The five bright planets – Mercury, Venus, Mars, Saturn, and Jupiter – are strung across the plane of the solar system from the east-northeast horizon to the southwest skyline. Simultaneously, five planets are visible.
This morning the five bright planets appear as beads on a necklace that is stretched across the morning sky.
Without the moon, Mercury shines low in the east-northeast, to the lower left of brilliant Venus. Mercury is in the sky for several more mornings until it disappears back into the sun’s glare. In two mornings it reaches its greatest separation (elongation) from the sun. It never strays far from the sun’s glare, making it a challenge to view.
Brilliant Venus is to the upper right of Mercury. Before later twilight brightened the sky, Venus is visible 5.1° to the lower left of Aldebaran. This star along with the Hyades star cluster form the face of Taurus the Bull. The Pleiades star cluster is above the scene.
Meanwhile, Mars is the lone bright “star” in the southeast among the dim stars of Cetus. This morning it is 2.7° to the upper left of 20 Ceti (20 Cet on the photo). A binocular is needed to see the starfield.
Mars is marching eastward. It begins the illusion of retrograde motion in early September as Earth approaches and passes the planet. Earth is between the sun and Mars on October 13, 2020. On this date, the sun and planet are in opposite directions from Earth. Near opposition the outer planets are closest to Earth and brightest in the sky.
Saturn and Jupiter are farther west in eastern Sagittarius. The planets are retrograding – moving westward compared to the background stars. With a binocular check the planets’ positions compared to the starry background. This morning Saturn is 4.3° to the lower right of Sigma Capricorni (σ Cap), while Jupiter is 4.0° to the lower right 56 Sagittarii (56 Sgr).
Jupiter was at opposition last week and Saturn is at opposition today. Jupiter and Saturn appear to reverse their directions in September. Then Jupiter inches toward Saturn and passes it on December 21, 2020 for a Great Conjunction.
Continue to look for the five planets for the next several days.