Category: Feature

2019, March 25-31: Mars Passes the Pleiades

Late in March, step outside about 90 minutes after sunset.  (Check the sunset time for your location.)  Orion is less than halfway up in the southwest.  Taurus, with its star clusters — the Pleiades and Hyades — are farther to the right (north) of Orion.  With the yellow-orange star Aldebaran, the stars of the Hyades make a letter “V.”  The Pleiades, a cluster of bluish stars that resemble a miniature dipper, are farther to the right.  This tiny cluster may have initially caught your attention out of the corner of your eye, as you first looked up.  Take a look with binoculars, as a telescope has too much magnification to take in all the Pleiades or Hyades.  In the Pleiades you may see a few dozen stars though your binoc.  The stars are vivid blue, indicating blazing high temperatures.

Mars, an orangish looking bright “star,” is to the lower left of the Pleiades cluster.  Each night Mars moves closer to the cluster, and passes closest on March 30.  Take a look each night to see Mars’ movement through space compared to the starry background.

We are referencing the cluster’s bright star, Alcyone, in the measurements.

One degree is the twice the size the full moon appears in the sky.

Watch Mars move closer and then past the cluster as the month closes.

  • March 25: Mars is 4.9° to the lower left of Alcyone.
  • March 26: Mars is 4.3° to the lower left of Alcyone.
  • March 27: Mars is 3.9° to the lower left of Alcyone.
  • March 28: Mars is 3.6° to the lower left of Alcyone.
  • March 29: Mars is 3.3° to the lower left of Alcyone.
  • March 30: Mars passes 3.1° to the lower left of Alcyone and the Pleiades, a beautiful view through a binocular.
  • March 31: Mars is 3.2° to the lower left of Alcyone. Tonight Mars is nearly the same distance as last night and slightly higher in the sky.
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2019: Winter Morning Planet Parade Album

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On a recent trip to a more southerly latitude, the morning planets presented themselves high in the sky.  This album shows them on the mornings of February 28, March 1, and March 2, 2019.  When travelling farther south, the southern stars and planets appear higher in the southern sky.

2019: Saturn’s Year in Sagittarius

Magnificent Saturn (NASA Photo)

During 2019, Magnificent Saturn has a dramatic display in the southern skies throughout the year.  It is headed toward a Great Conjunction with Jupiter in 2020.  During this appearance Venus passes the planet twice.

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Photo Gallery

Other Feature articles:

Saturn in eastern Sagittarius (Constellation image from Starry Night Pro)

Saturn appears in front of the stars of Sagittarius, although a little farther east compared to its location in 2018.  It appears to the upper left of the famous stars of The Teapot of Sagittarius.  To the unaided eye, the planet appears as a bright yellow-orange star.

Saturn: The Apparition Begins at Conjunction

Saturn revolves around the sun slowly, one orbit in nearly 30 Earth years.  The planet does not move very far against the background of stars.  Since it is heading toward a region of dim stars, the starry background is better known by their catalog names than their common names. Saturn starts its apparition about 4° to the upper left of Nunki (σ Sag, m = 2.0).  During the apparition, the Ringed Wonder moves beneath three other stars in the constellation: Pi Sagittarii (π Sgr, m = 2.9), Omicron Sagittarii (ο Sgr, m = 3.8), and Xi2 Sagittarii (ξ2 Sgr, m = 3.5). (The “m” number indicates the brightness of a star.  The lower the number the brighter the star.  Venus has a negative number because of its brilliance.  The stars listed here are dimmer stars, visible to most observers, but they are not easily seen near street lights.  A binocular helps to distinguish them in the sky.)

Saturn at conjunction, January 1, 2019.

Saturn’s apparition begins with its solar conjunction on January 1, 2019.  Saturn is behind the sun and largely invisible to us.  It rises with the sun, crosses south near noon, and sets with the sun in the west.  As Earth, moving much faster than Saturn, begins to close the space to Saturn, the Ringed Wonder appears in the morning sky.

The morning sky during 2019. The chart shows the rising time of planets, bright stars near the planets’ paths and the moon (circles), along with the three phases of twilight. White boxes indicate conjunctions.

As the chart above indicates, Saturn slowly rises into the morning sky, rising earlier each day.  By January 11, Saturn rises at Civil Twilight, when the sun is 6° below the horizon.  The sky is bright at 30 minutes before sunrise.  Eleven days later it rises at Nautical Twilight, about 60 minutes before sunrise, when the sun is 12° below the horizon.  Thirty minutes later it is low in the southeast, visible with a binocular.  On February 3, it rises at the beginning of twilight (Astronomical Twilight).  It becomes easier to see without optical assistance.  It joins brilliant Morning Star Venus and bright Jupiter in the southeast before sunrise.

The First Venus Conjunction

On February 18, Venus passes 1.1° to the upper left of Saturn.  Jupiter is far to the upper right of Saturn.

This chart displays Saturn’s apparent motion during 2019

All the objects beyond Earth’s orbit display an unusual pattern midway through their apparitions, retrograde motion.  The planet appears to move backward against the stars.  Our ancestors were captivated with explaining this unusual motion, especially when Earth was considered to be at the center of the universe.  Today we understand this is an illusion of our faster moving Earth passing the slower moving outer planets.  Retrograde motion occurs for Mercury and Venus as well, but it is from their faster speeds around the sun.  The chart above shows the retrograde pattern of Saturn in eastern Sagittarius.

This chart shows more detail in Saturn’s retrograde motion, along with the dimmer background stars. Two conjunctions with Venus are displayed.

The chart above shows a more detailed view of Saturn’s motion against eastern Sagittarius, along with the two conjunctions with Venus.

Saturn at Morning Quadrature

Saturn continues to rises earlier but gently moves eastward along its celestial path and against the starry background.

Saturn appears 90° west of the sun on April 9, 2019. Look for it in the south near sunrise.

By early April Saturn is 90° west of the sun, appearing in the south near sunrise. The planet rises at about 2:30 a.m. CDT.  It is about 26° up in the south as sunrise approaches.  By late April, Earth closes in on Saturn and the planet seems to stop moving eastward and it begins to retrograde on April 29.  (See the two time-lapse charts above that show Saturn’s apparent motion compared to the starry background.)

Saturn at Opposition

By mid-May, Saturn is rising around midnight (CDT).

Saturn at Opposition, July 9, 2019

Earth is rapidly catching Saturn.  The planet continues to rise earlier and on July 9, it rises in the southeast at sunset  The sun and Saturn are on opposite sides of Earth.  When the sun sets, Saturn rises.  At midnight, Saturn is south, opposite 12 hours when the sun is south (at noon).  Saturn sets in the southwest at sunrise. Opposition.  This occurs about in the middle of the planet’s retrograde motion.

Saturn then rises before sunset appearing higher in the southeast as the sky darkens.  By mid-September Saturn’s retrograde motion slows and the planet stops moving westward compared to the starry background on September 17.

Saturn is in the south near sunset on October 7, 2019

A few weeks later, Saturn appears 90° east of the sun, meaning it’s in the south at sunset.

A Second Venus Conjunction

Saturn is then farther west at sunset; it is heading toward its solar conjunction.

Venus passes Saturn on December 10, 2019.

As Saturn heads towards that solar conjunction in early 2020, Venus, during its evening apparition, passes 1.8° to the lower left of Saturn in the southwest.  This occurs on December 10, 2019.  Look about one hour after sunset.

Saturn Toward Conjunction

Saturn then begins to disappear into bright evening twilight in the western sky, the reverse of how it appeared in the morning sky. The events:

  • December 19, Saturn sets at Astronomical Twilight.
  • December 28, Saturn sets at Nautical Twilight.
  • January 5, 2020, Saturn sets at Civil Twilight.
Saturn returns to its solar conjunction on January 13, 2020.

Saturn then seems to move behind the sun for its solar conjunction, January 13, 2020.

In Saturn’s next apparition, Jupiter passes it in late December 2020.  This apparition ends with Jupiter about 17° west of Saturn.

Saturn and the Moon

The moon appears near Saturn several times during the apparition.  If you observe Saturn just once a month when the moon is nearby, you’ll see a complete cycle of moon phases.

Before Opposition Separation After Opposition Separation
February 2 3.1° July 15 1.8°
March 1 3.2° August 11 3.3°
March 29 3.0° September 7 5.5°
April 25 2.7° October 5 2.9°
May 23 5.7° November 1 3.7°
June 18 1.3° November 29 1.9°
December 27 5.6°

2018-2019: Jupiter Dances with the Snake Handler

Jupiter during its 2017-2018 apparition

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2018-2019 Photo Gallery

During its 2018-2019 apparition, Jupiter appears among the southern stars of Ophiuchus, the Snake Handler.  Just one apparition before its Great Conjunction with Saturn, Jupiter has two conjunctions with Venus.  Jupiter moves through southern Ophiuchus in front of dimmer stars  Its passage is worth noting in a dark sky or with binoculars.

The positions of Jupiter, sun and Earth at Jupiter’s conjunction on November 26, 2018.

Jupiter passes behind the sun early in the morning on November 26, 2018.  At this solar conjunction, Jupiter is not visible as it is hiding in the sun’s glare.   The chart above shows the position of Jupiter, sun and Earth at Jupiter’s conjunction.  From Earth, Jupiter is “behind” the sun.

Jupiter appears in front of the stars of Ophiuchus, the Snake Handler, during its 2018-2019 appearance.
(Artwork from Starry Night Pro)

The chart above shows the position of Jupiter in June 2019 compared to the background stars.  The sun, moon, and planets appear to move in front of a seemingly fixed background of stars we call the constellations.  They make familiar patterns.  The 88 constellations are also made of bright and dim stars outside those figures.  Constellation boundaries are irregularly-shaped patches of sky resembling a jumbled quilt or counties in a state.

To some, Ophiuchus is the “newly discovered 13th sign of the zodiac.”  This announcement is made every few years, but the constellation has existed since constellations were invented to track the skies of our ancestors.  There’s nothing new here.  The sun appears to move in front of Ophiuchus from about November 30 through December 17, 17 days compared to the 6 days it’s in front of the stars of Scorpius.  For most of its appearance during the next year, Jupiter shines from in front of stars of Ophiuchus’ feet.

This chart shows the relative motion of Jupiter compared to the background stars of Ophiuchus (Oph)
from December 24, 2018 through November 24, 2019.  Jupiter has two conjunctions with Venus
during this apparition. Greek letters are used to name the dimmer stars in the sky.

The planets appear to move eastward as they revolve around the sun.  They rise in the east and set in west each day as our planet rotates.  Jupiter moves slowly eastward compared to the distant stars, taking nearly 12 years to through all the constellations.  As our planet, moving 12 times faster, catches Jupiter nearly every year, Jupiter seems to stop moving eastward (April 10, 2019) and seems to move backwards or retrograde.  This is an optical illusion.  As it retrogrades, our planet passes between Jupiter and the sun (opposition, June 10, 2019).  After we pass by, Jupiter seems to stop retrograding (August 11, 2019) and appears to resume its forward or direct motion.  The illusion of the retrograde motion was one of the early challenges to explain.  If the earth were stationary, then must be a series of hoops that carried the planets.  The secondary hoops moved backwards at regular intervals, depending on the planet.  When it was clearly demonstrated that the earth moves (not an easy feat that was only demonstrated after the development of larger telescopes). the retrograde pattern was easily explained by a faster moving inner planet moving past a slower moving outer planet.

This chart shows the rising time of Jupiter and other bright celestial objects from Jupiter’s conjunction
until it rises 5 hours before sunrise.  Conjunctions with Mercury, Antares, and Venus are shown with
boxes.  The rising of the moon is shown with circles.  When the lines of two objects cross, they rise at the
same time.  Conjunctions can occur a few days before or after the intersection of the lines.  Chart
made from data by the U.S. Naval Observatory for Chicago, Illinois.

Slowly after conjunction, the planet begins to climb into the morning southeastern sky.  By December 3, it rises about 30 minutes before sunrise. Locate it in bright twilight with a binocular.  Watch it appear higher in the sky each morning at the same time.  Ten days later it rises about an hour before sunrise.  Thirty minutes before sunrise, it is only 5° up in the east-southeastern sky,  Near the middle of December, Jupiter rises at Nautical Twilight, about 65 minutes before sunrise.  At this time, the horizon is barely distinguishable.  Historically, this was important for sailors to be able to make celestial measurements for navigation that references the natural horizon with at sea.

Jupiter, Mercury, and Antares

As Jupiter emerges into the morning sky from its solar conjunction, it is grouped with Mercury and Antares.  Mercury passes Jupiter on December 21.  Brilliant Venus is far to the upper right of the grouping; it closes the gap early during Jupiter’s apparition.  Here are the details of the grouping.

This chart shows a time-lapse of 5 mornings, 45 minutes before sunrise, during late December.  Look
into the southeastern sky.  A binocular helps locate the dimmer stars.

  • December 19: Jupiter is 0.8° to upper right of Omega Ophiuchi (ω Oph) and 5.3° to the upper left of Antares, although the star is only 3° in altitude. Use a binocular to find it.  Bright Mercury is 2.5° to the upper right of Jupiter and 1° to the upper right of Psi Ophiuchi (ψ Oph).
  • December 20: At 45 minutes before sunrise, Jupiter is nearly 7° up in the southeast. The planet is 5.2° to the upper left of Antares.  Mercury is 1.6° to Jupiter’s upper right.

  • December 21: Jupiter and Mercury are 0.9° apart this morning. Jupiter is 0.6° to the upper left of Omega Ophiuchi. Mercury, Jupiter, and Antares are nearly in a line spanning 6.1°. Today marks two years until the Great Conjunction of Jupiter and Saturn, when they appear 0.1° apart!
  • December 22: At 45 minutes before sunrise, Mercury is 1.2° to the left of Jupiter. Jupiter is 25.2° to the lower left of brilliant Venus this morning.  Watch Venus close the gap during the next month

.

  • December 23: Jupiter rises over 100 minutes before sunrise, at the beginning of twilight.  This morning, Jupiter passes 5.2° above Antares.  The Giant Planet appears 0.2° to the upper left of Omega Ophiuchi. Use a binocular or a small aperture telescope to resolve the pair.  The Jupiter-Mercury gap has grown to 2°.  Mercury is to the lower left of Jupiter.

By year’s end Jupiter rises over 2 hours before sunrise.  It is well off the southeastern horizon as twilight progresses.

Venus-Jupiter Conjunction

Early in the new year, Jupiter rises into the sky before twilight begins. Brilliant Venus and Jupiter approach a morning conjunction.  Venus rapidly moves eastward among the stars, about a degree a day compared to Jupiter.  They are heading for a widely-spaced conjunction on January 22. Watch the Venus-Jupiter gap close:  January 5, 15°; January 11, 10.1°; January 17, 5.1°.

  • January 1, 2019: At the beginning of the new year, look for a wide grouping of the crescent moon, two planets, and a bright star. At 45 minutes before sunrise, the waning crescent moon is 29° up in the south-southeast, slightly below a virtual line that connects Zubenelgenubi (α Lib) and Zubeneschamali (β Lib).  Venus is 4.7° to the lower left of the moon.  Jupiter, 11° up in the southeast, is 18° to the lower left of Venus.  Antares is 5.5° to the lower right of Jupiter.

  • January 22: At mid-twilight, 40 minutes before sunrise, the Venus-Jupiter pair appears 22° up in the southeast. Venus is 2.4° to the upper left of Jupiter in this widely-space conjunction. Watch Venus move away from Jupiter on the mornings that follow.

By the end of January, the Venus-Jupiter gap is nearly 8° .  Jupiter rises nearly 3 hours, 30 minutes before the sun.  At an hour before sunrise, Jupiter is 19°  up in the southeast.

Jupiter at Morning Quadrature

The positions of Jupiter, sun and Earth when Jupiter is 90° from the sun on March 13, 2019.

During March, Jupiter continues to rise earlier.  On March 1, it rises just after 2 a.m. local time.  On March 13, Jupiter around 2:30 a.m. CDT.   This morning it is 90° west of the sun.  As twilight begins, this Giant Planet is 25°  up in the south.  The planet continues to rise earlier and appear farther west during morning twilight.

On April 10 Jupiter begins to retrograde.  It is 15° to the upper left of Antares.  During the next six weeks, with a binocular, watch Jupiter move through the dim star field of southern Ophiuchus.  By April 19, the planet is rising before midnight, continuing to rise earlier each evening.  The time of its rising is very noticeable each week.  Our planet is catching Jupiter.

Jupiter at Opposition

The positions of the sun, Earth and Jupiter when Jupiter is at opposition, June 10, 2018.

On June 10, Earth passes between Jupiter and the sun.  Jupiter is nearly 400 million miles away. The sun and Jupiter are in opposite directions in the sky.  When the sun sets, Jupiter rises in the southeast.  It is south around midnight, setting in the southwest at sunrise.  After opposition, Jupiter rises in the sky before sunset.  By month’s end, Jupiter is well above the southeastern horizon as the sky darkens after sunset.

Jupiter continues to retrograde, reaching the farthest western point on August 11, 2019.


This chart shows the setting time of Jupiter and other bright celestial objects beginning with Jupiter setting 5 hours after sunset until its conjunction.  A conjunction occurs with Venus on November 24.
The setting moon is shown with circles.  When the lines of two objects cross, they set at the
same time.  Conjunctions can occur a few days before or after the intersection of the lines.  Chart
made from data by the U.S. Naval Observatory for Chicago, Illinois.

Jupiter appears on the setting chart in mid-August, when it sets 5 hours after sunset.  Notice how the Jupiter setting curve angles away from the Antares setting line and toward the Saturn setting line.  Jupiter’s setting curve intersects with Venus, indicating a conjunction (November 24).

Jupiter at Evening Quadrature

The positions of the sun, Earth, and Jupiter when Jupiter is 90° east of the sun, September 8, 2019.

Jupiter continues to appear higher in the sky each night as Earth pulls away.  On September 8, Jupiter is 90° from the sun in the evening sky,  Jupiter is in the south at sunset, setting at nearly 11:30 p.m. CDT.

From this point, Jupiter appears closer to the southwestern horizon at sunset.

A Second Venus-Jupiter Conjunction

During Venus’ evening apparition late in 2019, Venus passes Jupiter again.  Not a close (epoch) conjunction, but the planets are closer than January’s meeting.  The pair appears 1.4°  apart.  Start watching the Venus-Jupiter gap early in the month.  Here are the separations:

Nov 4:     20°
Nov 9:     15°
Nov 14:   10°
Nov 19:     5°
Nov 22:     2°

After the conjunction, the gap:

Nov 25:     2°
Nov 27:     7°

Toward Conjunction

On the evening of the conjunction with Venus, Jupiter sets as twilight ends, so begins its slow slide back into bright sunlight toward its solar conjunction.  As the Venus gaps grows, Jupiter sets at Nautical Twilight, (66 minutes after sunset) on December 6.  It sets at Civil Twilight (30 minutes after sunset) on December 17.  Civil Twilight is about the time that street lights turn on.

The positions of the sun, Earth, and Jupiter when Jupiter returns to its solar conjunction, December 27, 2019.

Jupiter’s appearance ends with its solar conjunction on December 29, 2019.  It then begins another appearance in the morning sky in 2020, the year of the Great Conjunction with Saturn when Jupiter passes very close to Saturn!

Jupiter and the Moon

Dates when Jupiter and the moon appear together

Before Opposition.

January 3:  3.5°
January 30/31:  6.2°/5.7°
February 27: 2°
March 27: 4.3°
April 23: 1°
May 20:  4.7°

After Opposition

June 16: 4.7°
July 13: 7.8°
August 9: 2.2°
September 5: 4°
October 3: 1.8°
October 31: 4.5°
November 28: 5.8°

Venus in the Morning Sky, 2018-2019

Figure 1:  Venus shines in the morning sky with a crescent moon on September 17, 2017

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Photo Gallery

Venus as a Morning Star, 2018-2019

Venus returns to the morning sky in late 2018 and shines from the eastern sky until the middle of summer 2019.  The photo above (Figure 1) shows Venus on September 17, 2017, during the last morning appearance.  During  this appearance Venus has conjunctions with Jupiter and Saturn, and a close approach to Mercury.  Venus rises very rapidly in the morning sky after its inferior conjunction on October 26, 2018.  It seems to be chasing Spica into the sky.  By mid-December, Venus rises nearly four hours before sunrise, then begins to slide back toward the sun, taking nearly eight months to reach superior conjunction.

Bookmark this page to return to it follow the progress of Venus in the morning sky,

For readers wanting a detailed and more technical description of the appearance, click here.

Figure 2:  Venus at Inferior Conjunction: October 26, 2018

The morning appearance begins on October 26, 2018, when Venus moves between the earth and sun (inferior conjunction) (Figure 2). It is typically not visible at these times, but Venus is not lined up with the earth and sun. It passes below imaginary line between the earth and sun. Venus might be visible in the clear sky. Around noon, stand under an overhang that blocks the sun. Binoculars or a small telescope might be needed to initially locate it. It is very important not to point any optical instrument at the sun. The light collecting properties of the binoculars or a telescope can damage the device or cause irreparable damage to eyes if you are looking through them. With optical help from a telescope, Venus displays a very thin crescent.

Figure 3:  The rising times of stars and planets compared to sunrise.  The rising of Venus compared to sunrise
is displayed on the green line.  The moon’s rising is shown by the circles.

Venus then quickly moves into the morning sky the chart above (Figure 3) shows the rising time interval of Venus compared to sunrise; the rising time intervals for stars and other planets are shown as well. The circles show the rising time intervals for the moon.  The setting times for Jupiter and Saturn are included.  This occurs in the western sky.  When these planets set at sunrise, they are at opposition.

When the rising line of Venus crosses the rising line of another star or planet they rise at the same time. They are closest within a day or so of this intersection. When a moon circle appears near the rising line, the moon appears near Venus within a day or so.

The three phases of twilight: Civil Twilight, when the sun is 6° below the horizon; Nautical Twilight, sun is 12° below the horizon; and Astronomical Twilight, sun is 18° below the horizon at this time; the sky is as dark as it gets naturally.

This chart was composed from data by the US naval observatory for Chicago, Illinois.

Note that Venus appears seemingly suddenly in the morning sky. It appears to be chasing the star Spica. After Venus reaches its greatest brilliance and greatest elongation, it begins a slow fade into the sun’s glare. On the way it passes Jupiter, and Antares, and Saturn, along with other sign posts.

Venus and Spica, November 2018

Venus seems to be chasing Spica into the sky.  These charts show the pair about 30 minutes before sunrise.

Figure 4:  November 4, 2018, Venus is
4.4° below Spica.

  • November 4 (Figure 4): Only nine days after its conjunction, Venus rises an hour before sunrise this morning it is 4.4° below Spica with the waning crescent moon nearly 27° above Spica; notice the contrast of brightness. Venus is about 100 times brighter than Spica.

Update:  November 10, 2018


Figure 5:  Venus is closing the gap on Spica.

  • November 6 (Figure 5): Brilliant Venus is 3.6° below Spica with the waning crescent moon 9° to the left of the planet. Watch Venus close the gap on Spica during the next week.
  • November 9: Venus rises at the beginning of twilight, about 100 minutes before sunrise. After today, Venus rises before the beginning of twilight until March 14, 2019.
Figure 6: Venus closes about one degree of Spica in mid-November. There is no conjunction but this is the closest approach — a quasi conjunction
  • November 14: (Figure 6): The Spica chase ends when brilliant Venus closes to 1.2° of the star.  Venus does not pass Spica.  Because the separation is less than 5°, this is known as a “quasi-conjunction.”

Venus at Greatest Brightness

Figure 7:  This chart shows the location of Venus
during its 11-day stage of greatest brightness.

  • November 24: Now rising over 3 hours before the sun, brilliant Venus starts its stage of greatest brightness (Figure 7). For the next 11 days it displays its greatest visual intensity. It is important to note that this is not a singular event, but the duration of this greatest brightness occurs across several mornings.  More formally, Venus is near its greatest illuminated extent, defined as a geometrical configuration when Venus has an elongation of 40° – midway between inferior conjunction and greatest elongation.  This occurs December 1, when Venus’ illuminated portion covers more area of the sky than any other time during its apparition. (For a more technical explanation of greatest illuminated extent, see https://tinyurl.com/venus-greatest-illuminated.)  For our description, greatest brilliancy occurs during a 11-day period when Venus displays its greatest visual brightness.  Its brightness measured with light-sensitive equipment may slightly change, but our eyes cannot perceive that minute difference. 


Figure 8:  Look for Venus and Sirius about 2 hours before sunrise in late November.

  • November 29: As Venus is in the middle of its stage of greatest brightness, notice that it is about the same altitude (16°) as brightest star Sirius in the southwest, at about 100 minutes before sunrise. While it is not appropriate in formal astronomy to visually compare respective brightness of objects that are widely separated (101° in this case), notice that Venus is distinctly brighter (about 25 times) than Sirius – the brightest planet compared to the brightest star. Venus is now 5.3° to the lower left of Spica, about two weeks after their quasi-conjunction (Figure 8).

A Morning Planet Dance

Figure 9:  The morning planet dance of Venus, Jupiter, and Mercury in late December 2018.

  • December 19:  Today is the greatest time interval between Venus rising and sunrise. While the Venus rising time is still 3:23 a.m. CST (in Chicago), sunrise changed 4 minutes earlier during the past week.  The gap between sunrise and Venus rising now decreases, on average, about 1 minute each morning until Venus rises at Astronomical Twilight less than three months from this morning. Brilliant Venus is 28° up in the southeast, 4.3° above Zubenelgenubi (α Lib).  Bright Jupiter is 27° to the lower left of Venus.  Jupiter is 0.8° to upper right of Omega Ophiuchi (ω Oph) and 5.3° to the upper left of Antares, although the star is only 3° in altitude.  Use binoculars to find it.  Mercury is 2.5° to the upper right of Jupiter and 1° to the upper right of Psi Ophiuchi (ψ Oph). (See Figure 9)
  • December 20: This morning Jupiter is 1.6° below Mercury and 0.6° to the upper right of Omega Ophiuchi. Mercury is 0.6° to the lower left of Psi Ophiuchi.
  • December 21: Mercury, Jupiter and Antares are nearly in a line, spanning 6.1°; the Jupiter-to-Antares gap is 5.2°.  Jupiter is 0.9° to the lower right of Mercury, their closest separation, and 0.4° to the upper left of Omega Ophiuchi.
  • December 22: Jupiter is 1.2° to the right of Mercury (m = −0.4) and 0.2° to the upper left of Omega Ophiuchi.
  • December 23: Jupiter is 2° to the upper right of Mercury, which has an altitude of 5°.  The giant planet is 0.22° to the upper left of Omega Ophiuchi.  It passes 5.2° to the upper left of Antares and Mercury passes 6.1° to the upper left of the star.  Venus is nearly 25° to the upper right of Jupiter and 2.9° to the upper left of Zubenelgenubi.

Venus at Morning Greatest Elongation

Figure 10:  Venus at greatest elongation,
January 5, 2009

  • January 5, 2019: Venus reaches its greatest elongation from the sun (47.0°) (Figure 10). It is 13.6° above Antares. Jupiter is 14.2° to the lower left of Venus and 5.9° from Antares.  Venus and Spica are 35.3° apart. Through a telescope, Venus is nearly the same angular diameter as Mars when it was at its closest last summer (July 31).  Venus appears at its morning half phase.

Venus-Jupiter:  A Widely-Spaced Conjunction

Figure 11:  Venus, Jupiter, and Antares,
January 17, 2019.  Venus
approaches Jupiter

  • January 17: At 6:15 a.m. CST (60 minutes before sunrise), brilliant Venus is 20° up in the southeast (Figure 11). Venus passes 7.8° to the upper left of Antares.  Bright Jupiter is 5.1° to the lower left of Venus and 7.2° from Antares.  Venus is now two times farther from Earth than when we marked its greatest brilliancy, 49 days ago.  Through a telescope, Venus’ terminator is slightly, but distinctly, convex — indicating a morning gibbous phase.

Figure 12: A widely-spaced Venus-Jupiter conjunction.

  • January 22: Venus passes to the upper left of Jupiter this morning in a widely-spaced conjunction (2.4°) (Figure 12). Venus is 22° up in the southeast at 6:30 a.m. CST (40 minutes before sunrise). Venus passes Jupiter (1.1°) again on November 24, 2019, when they appear in the western evening sky on Venus’ next evening apparition. Venus and Jupiter resume their close (epoch) conjunctions with a difficult-to-see grouping on February 11, 2021 (0.4°). An easier-viewed epoch conjunction occurs on April 30, 2022 (0.5°).  Both of these close conjunctions occur in the morning sky.

Venus continues to move eastward against the starry background, away from Jupiter and toward Saturn.

Venus-Saturn Conjunction

Figure 13:  A Venus-Saturn conjunction,
February 18, 2019

  • February 18: At 6 a.m. CST (about 40 minutes before sunrise), Saturn is 13° up in the southeast. This morning is the Venus-Saturn conjunction (Figure 13).  Venus is 1.1° to the upper left of Saturn.  As with Jupiter (described on January 22), Venus has another conjunction with Saturn in the evening sky later this year.  On December 10, 2019, they appear 1.8° apart.  This is followed by a very close conjunction (0.4°) on February 6, 2021 in the morning sky close to sunrise.

Heading Into Twilight & A Close Approach to Mercury

  • March 14: Venus rises at Astronomical Twilight (93 minutes before sunrise) and for the rest of this apparition rises earlier during the phases of twilight. Through a telescope, Venus is growing in its morning gibbous phase. This morning, Jupiter is 90° west of the sun.  It is 52° to the upper right of Venus.  Saturn is 20.8° to Venus’ upper right.

Figure 14: A Venus-Mercury quasi-conjunction,
April 16, 2019

  • April 16: Venus and Mercury have a quasi-conjunction (4.3°) (Figure 14). (See the definition in the November 14 note.)  Mercury has a wide greatest elongation (27.7°), but the ecliptic is at a low angle for viewing. Even with its earliest rising on April 3, Mercury rose 8 minutes before Nautical Twilight, about 65 minutes before sunrise.  You’ll need binoculars to see it in the east-northeast sky.  This morning, Mercury rises 15 minutes after Nautical Twilight.

Figure 15:  A Venus-Mercury-Moon grouping,
May 2, 2019

  • May 2: The waning crescent moon (27.1 d) is 4.3° to the lower right of Venus. Mercury is 8.5° to the lower left of Venus, just above the horizon (Figure 15).  The time interval between Astronomical Twilight and sunrise grows 24 minutes from this morning through mid-June.  While Venus is rising at the same time interval before sunrise for the next month, it appears in a brighter sky.  Note this on the rising chart (Figure 3).

A Bright Twilight Conjunction With Aldebaran

Figure 16:  Venus-Aldebaran,
June 17, 2019

  • June 17: Now rising less than hour before sunrise, Venus passes 4.7° to the upper left of Aldebaran (Figure 16). This will test your observing skills with a telescope. Venus is in a slow slide into the sun’s glare, rising, on average, about 1.7 minutes later each day.

Heading Toward Conjunction

Figure 17:  Venus and the moon, July 1, 2019

  • July 1: At 4:55 a.m. CDT (35 minutes before sunrise), a very thin crescent moon (28.0 d) stands 6.3° to the right of Venus (Figure 17). The planet is 3.6° off the east-northeast horizon, another challenge for your observing location and your observing skills.

July 21: Clearly rising in bright twilight, Venus rises farthest north, azimuth equals 57°, the same position the sun rose at the summer solstice. Tomorrow, Venus rises at Civil Twilight (sun’s altitude is −6°), about 30 minutes before sunrise.Figure 18:  Venus at Superior Conjunction,
August 14, 2019

  • August 14: Venus is at superior conjunction, 1:07 a.m. CDT (Figure 17).  This appearance of Venus ends.

Appearances with Moon

  • November 6, 2018 (8.9°)
  • December 3, 2018 (5.6°)
  • January 1, 2019 (5.4°)
  • January 31, 2019 (2°)
  • March 2, 2019 (4.3°)
  • April 1, 2019 (8.7°)
  • May 2, 2019 (4.3°)
  • June 1, 2019 (6°)
  • July 1, 2019 (6.3°)