Category Archives: Sky Watching

2020, August 14: Venus, Crescent Moon, Sirius Before Sunrise

Venus, moon, Sirius, August 14, 2020
2020, August 14, 2020: One day before their close grouping, the crescent moon is 13° to the upper right of Morning Star Venus. Sirius is making its first morning appearance in the east-southeast.

Look for Venus, crescent moon, and Sirius in the eastern sky before sunrise.

by Jeffrey L. Hunt

Venus, the waning crescent moon, and Sirius appear in the eastern sky this morning before sunrise.

Tomorrow morning the moon and Venus appear in a close grouping.  Get your camera ready.

This morning the moon is nearly 13° to the upper right of the brilliant Morning Star.

Meanwhile, Sirius is making its first morning appearance.  The night sky’s brightest star is low in the east-southeast sky.  During the next few mornings look for it without optical assistance.  It appears in the photo above because of the short time exposure.  It is visible through a binocular.

Here is a daily summary about the planets during August.

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20th anniversary ISS poster from NASA

2020, September 17: Jupiter, Saturn, International Space Station

After the sky cleared today, the International Space Station made a bright pass across the mid-northern latitude states this evening near Jupiter and Saturn in the sky. The ISS was brighter than the planet Jupiter.

2020, August 12: Jupiter, Saturn Evening Stars

 

Jupiter and Saturn, August 12, 2020
2020, August 12: Saturn is 8.1° to the lower left of the Giant Planet. In the starfield, Jupiter is 1.4° to the right of 50 Sagittarii (50 Sgr), while Saturn is 2.4° to the lower left of 56 Sagittarii (56 Sgr).

Bright Jupiter and Saturn shine from the southeastern sky after sunset during August 2020.

by Jeffrey L. Hunt

Bright Jupiter and Saturn shine from the southeastern sky during late evening twilight this evening. 

Saturn is 8.1° to the lower left of the Giant Planet. The gap between them continues to widen during the next month. In the starfield, Jupiter is 1.4° to the right of 50 Sagittarii (50 Sgr on the photo) and 2.9° to the lower left of Pi Sagittarii (π Sgr), while Saturn is 2.4° to the lower left of 56 Sagittarii (56 Sgr).

This planetary pair passed opposition last month and the planets continue to retrograde in eastern Sagittarius.

Retrograde motion is a illusion that occurs when our faster moving Earth catches up to the outer planets, passes them, and moves away.

Jupiter retrogrades until September 12, and Saturn ends its westward illusive apparent motion on September 28.

Then Jupiter approaches Saturn for a once-in-a-generation Great Conjunction on December 21, 2020.  This is the closest conjunction since 1623.

As the evening progresses, Mars appears in the eastern sky as the midnight hour approaches.

Venus is above the horizon by 3 a.m.  Tomorrow morning (August 13), Venus moves into Gemini.

Venus and the crescent moon make a beautiful grouping on August 15.  Get your camera ready!

The window is quickly closing to see the four brightest planets in the sky together.  Venus is moving eastward compared to the starry background, while Jupiter is moving westward. Venus rises as Jupiter sets on August 25. Saturn follows in early September.  If you’re an early riser, what is the last date you see all four together?  You’ll need clear horizons in the east-northeast and toward the southwest.

The first sightings of Sirius by the unaided eye occur this week about 45 minutes before sunrise.

Here is a daily summary about the planets during August.

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Full moon

2020, October 31: Rare Halloween Full Moon

A rare Halloween Full Moon, 76 years in the making, is visible across most of the planet in 2020. This could be called a “Blue Halloween Moon.”

2020, August 12: Mars, A Planetary Dance

Mars begins its planetary dance as it nears its closest approach to Earth and its opposition with the sun.

by Jeffrey L. Hunt

Bright Mars shines from the south-southeastern sky during the early morning hours.  It is moving eastward in a dim starfield of Pisces.

Within a month, Mars begins to retrograde. This is an illusion as our planet approaches and passes the Red Planet and all other planets, minor planets, and comets that are farther away from the sun than our home planet.

As Earth approaches Mars, the Red Planet becomes brighter, but not much larger in appearance to the human eye.  While it can double in its apparent size through a telescope, the increase is imperceptible to the human eye (unlike what is shown in the social media memes.)

Mars rises in the east before 11 p.m. and shines high in the southern sky before sunrise.  As it rises in the evening, Jupiter and Saturn are in the south.

Four planets – Jupiter, Saturn, Mars, and Venus – are visible around 3 a.m., shortly after Venus rises, but clear horizons are necessary to see the planetary quartet together.  And the window to see all four in the morning sky is closed on August 25.

The charts in this article show the entire retrograde path of Mars along with the view of the two planets as they revolve around the sun.

On the photo above, Mars is 3.1° to the upper left of 89 Piscium (89 Psc) and 1.1° below Mu Piscium (μ Psc).  It is moving eastward in a path that is taking it toward and above, Nu Piscium (ν Psc).

Mars seems to stop moving forward and begins to retrograde on September 9, below Omicron Piscium (ο Psc).  The planet then moves westward, passing ν Psc again. Earth and Mars are closest on October 6, 2020, when the Red Planet appears near μ Psc.

Earth passes between the sun and Mars on October 13, This is known as opposition.  The planet rises in the east as the sun sets in the west.  As Earth rotates, the planet appears farther west during the night, in the south around midnight, and sets in the west at sunrise.

At opposition, Mars is a few degrees to the right of μ Psc.

Mars continues to retrograde until November 13, after it passes below 80 Piscium (80 Psc). It does not move as far west as Delta Piscium (δ Psc).  As it moves eastward against the starry background, it passes below Epsilon Piscium (ε Psc) and then Pi Piscium (π Psc), as the year ends.

Use a binocular to spot the dim stars in the near Mars and watch its planetary dance with the stars.

Venus appears in the eastern morning sky to the lower left of the Red Planet.

The first sightings of Sirius by the unaided eye occur this week about 45 minutes before sunrise.

Here is a daily summary about the planets during August.

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2020, August 12: Venus Last Morning in Orion

Venus in Orion, August 12, 2020
2020, August 12: Venus is 2.7° to the lower right of Eta Geminorum (η Gem) and 2.5° to the lower right of Mu Geminorum (μ Gem).

Brilliant planet Venus is moving through the “club” region of Orion.  Tomorrow it moves into Gemini.

by Jeffrey L. Hunt

On this peak Perseid meteor shower morning and the impending helical rising of Sirius, the brilliant Morning Star Venus, appears in the eastern sky.

This is the final morning that Venus is in the club area of Orion for this appearance.  Venus is to the lower right of Eta Geminorum (η Gem on the photo) and Mu Geminorum (μ Gem).

In this starfield, Venus is 2.7° to the lower right of η Gem and 2.5° to the lower right of μ Gem.

Notice that Orion’s shoulders – Betelgeuse and Bellatrix – appear to the right of the Morning Star.

The planet continues to move eastward – toward the lower left on the photo.

At the beginning of the month, Venus was near Zeta Tauri (ζ Tau), that appears near the top of the image.

Venus and the crescent moon make a beautiful grouping on August 15.  Get your camera ready!

Bright Mars is higher in the sky toward the south this morning.

The first sightings of Sirius by the unaided eye occur this week about 45 minutes before sunrise.

Here is a daily summary about the planets during August.

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Venus and Jupiter, August 18, 2012

The Harvest Moon

The Harvest Moon is the full moon that occurs nearest to the autumnal equinox in the northern hemisphere.

2020, August 11: Last Call, Four Morning Planets

 

2020, August: Last call for four morning planets.
2020, August 11: The four bright planets span the morning sky from the east-northeast horizon to the southwest skyline until August 25 when Jupiter sets as Venus rises. The moon is between Mars and Venus until August 15.

 

Venus, Mars, Saturn, and Jupiter are making their final appearance together during 2020.

by Jeffrey L. Hunt

For the next several mornings, Venus, Mars, Saturn, and Jupiter are visible in the sky together, spanning the celestial vault from the east-northeast horizon to the southwest skyline.  Locate a clear spot to view Venus and Jupiter simultaneously.

The chart above shows the sky at three hours before sunrise. The planets appear as overly bright stars.  Brilliant Venus is low in the east-northeast.  Mars is high in the southeast.  Bright Jupiter is low in the southwest, with Saturn to its upper left.   The moon appears in the with the planetary quartet until August 15.

Venus continues to step eastward in the stars of Orion until August 13 when it moves into the constellation Gemini.  Jupiter, at the western extreme of this morning planet parade, is retrograding in eastern Sagittarius.

The Venus – Jupiter gap continues to widen.  On August 25, the two planets are in opposite directions for us.  Jupiter sets as Venus rises, leaving three planets in the morning sky.  Saturn disappears below the southwestern horizon early next month, leaving Mars and Venus in the morning sky.

Venus in Orion, August 10, 2020
2020, August 10: Venus is 1.3° to the lower left of χ2 Ori and 2.8° to the lower right of Eta Geminorum (η Gem).

Venus and the crescent moon make a beautiful grouping on August 15.  Get your camera ready!

Mars in Pisces, August 9, 2020
2020, August 10: The moon is 12° to the left of Mars. The Red Planet is 2.4° to the upper left of 89 Piscium (89 Psc) and 1.6° to the lower right of Mu Piscium (μ Psc.)

Mars continues to march eastward in Pisces.  It is nearing a point where it appears to begin to retrograde.  The photo above shows the starfield where it appears for the next several weeks.  Mars appears to pass Mu Piscium (μ Psc on the photo) and move toward Nu Piscium (ν Psc).  Use a binocular to track Mars in the starfield.

The four planets are in the sky together for a short spell during early August 2021 as Mars disappears toward its solar conjunction in the west and Jupiter enters the evening sky, with Saturn and Venus between the two other planets.

Meanwhile, this year, Jupiter and Saturn are easy to spot in the southeast after sunset.  After the giant planet pair ends its retrograde next month, Jupiter approaches and passes Saturn on December 21, 2020 in a Great Conjunction, the closest since 1623.

On the morning of August 12, view the annual Perseid meteor shower.  While a brighter moon outshines the dimmer meteors, five or six meteors are visible each hour on the prime morning.

The first sightings of Sirius by the unaided eye occur this week about 45 minutes before sunrise.

Here is a daily summary about the planets during August.

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2020, August 9: Venus in Orion, Mars and Moon

Brilliant Venus and Mars shine in the morning sky.  Venus is in Orion and the gibbous moon appears near Mars.

Venus in Orion, August 8, 2020
2020, August 8: Brilliant Venus is 0.5° to the upper right of Chi2 Orionis (χ2 Ori).

by Jeffrey L. Hunt

This morning, Venus reaches its earliest rising time (2:25 a.m. CDT, Chicago, Illinois).  It rises at this time through August 17.  This morning it is in the club area of Orion.  The brilliant planet is 0.5° below Chi2 Orionis (χ2 Ori on the photo).  With a binocular, watch it move farther from the star, toward the lower left in the photo.

This time is short to see four planets – Jupiter, Saturn, Mars, and Venus, along with the moon – until next year.  An early observation, about 30 minutes after Venus rises, is needed too see them spread across the sky from the east-northeast horizon to the southwest skyline.

On August 15, catch the crescent moon with Venus. 

Mars and the moon in Pisces, August 9, 2020
2020, August 9: Mars is 1.2° to the upper left of the gibbous moon.

Mars and the moon are together this morning in the constellation Pisces.  The lunar orb is 1.2° to the lower left of the Red Planet.  Without a telescope, the bright planets resemble overly bright stars.  Through a telescope, the planets’ details are observed.

Mars is marching eastward.  In about a month, Mars reverses its direction and starts to retrograde, an illusion caused by our faster moving world overtaking the slower moving Mars.

On the morning of August 12, view the annual Perseid meteor shower.  While a brighter moon outshines the dimmer meteors, five or six meteors are visible each hour on the prime morning.

The first sightings of Sirius by the unaided eye occur this week about 45 minutes before sunrise.

Here is a daily summary about the planets during August.

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2020, August 18, 19: Observe Opposing Crescent Moons

Opposing Lunar Crescents
Opposition lunar crescents: Morning crescent followed by evening crescent on the next evening.

Opposing crescent moons are visible across eastern North America on the morning of August 18 and evening of August 19.

by Jeffrey L. Hunt

Opposing crescent moons are two observations of the moon on consecutive days around the New moon. The first step is observing the razor-thin waning crescent on the morning of August 18.  The New moon follows later in the day. On the evening of August 19, the second step is observing the moon’s thin waxing crescent that appears above the western horizon after sunset.

This is a challenge that involves a little planning, exceptionally clear weather, and unobstructed horizons.  Observers who try this often change locations to see each crescent.

Viewing this set of opposing crescents is region-specific.  The moons are visible for eastern North America including southern Mexico. (They might be visible from the Denver, Colorado region.  For the morning observation, the moon is less than 2° above the horizon for the morning observation in Utah.)  It might be possible for those in northern South America to see this is well.

The planning:  An astronomy program like Stellarium (stellarium.org) is great for locating the positions of stars, moon, and planets.  The program’s features include the ability to set your location (longitude, latitude) and time, among many others.  To locate the moon on August 18, locate the time of sunrise and set the program’s time for 30 minutes before sunrise.  Where is the moon in height above the horizon and its azimuth coordinate?  Find out the same for 30 minutes after sunset on August 19. 

Locate observing spots with clear horizons in the east-northeast and west-northwest. Record the times of the last sighting of the morning crescent on August 18 and the first sighting of the evening crescent on August 19.  The shortest interval between observations of the two crescents is 34 hours, 37 minutes by Robert C. Victor and Alexander Seidler on December 31, 2013 – January 1, 2014 from Palm Springs, CA.  The current opportunity predicts an interval of 38 hours, 41 minutes, This is certainly not the shortest recorded span because of longer daylight intervals during August, but worth the challenge attempting unusual observations of the lunar crescents.

Here’s what to look for in the Chicago, Illinois, area: 

August 18, 30 minutes before sunrise (5:34 a.m. CDT).  The crescent moon (1% illuminated) is nearly 3.0° in altitude in the east-northeast (azimuth 67°).

August 19, 30 minutes after sunset (8:15 p.m. CDT. The waxing crescent moon (1% illuminated) is 3.1° in altitude in the west-northwest (azimuth 283°).

The conditions for observing these crescents occurs about every 22 months, so that the moon is  north of the plane of the solar system (in the northern hemisphere); the lunar orb is near perigee (August 20); and the moon is appropriately spaced from the sun at sunrise and sunset.

So you know where and when to look.  Show up at the locations an hour before sunrise for the morning view and at sunset for the evening attempt.  Report your observations in the comments.

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2020, August 5: Brilliant Venus Tours Orion, Mars in Pisces

Venus in Orion, August 5, 2020
2020, August 5: Venus is 1.1° to the upper right of the star Chi1 Orionis (χ1 Ori) and 3.3° below Zeta Tauri (ζ Tau), the Southern Horn of Taurus.

Venus and Mars shine from the morning sky before sunrise. Venus moves into Orion, while Mars marches eastward in Pisces.

by Jeffrey L. Hunt

This morning – over 90 minutes before sunrise – brilliant Venus is on its first day of eight days touring the northern reaches of Orion, in the Hunter’s club.  This morning Venus is 1.1° to the upper right of the star Chi1 Orionis (χ1 Ori on the photo) and 3.3° below Zeta Tauri (ζ Tau), the Southern Horn of Taurus.  With a binocular watch Venus pass χ1 Ori and move toward Chi2 Orionis (χ2 Ori).

Through a telescope the planet’s is a thick morning crescent phase that is slightly less than half full.

Mars in Pisces, August 5, 2020
2020, August 5: Mars is 0.5° to the upper left of 89 Piscium (89 Psc) and 3.4° to the lower right of Mu Piscium (μ Psc).

Farther westward, Mars is high in the south-southeast, marching through the dim stars of Pisces.  This morning it is 0.5° to the upper left of 89 Piscium (89 Psc) and 3.4° to the lower right of Mu Piscium (μ Psc).

The bright moon appears farther west in this morning sky.  The moon appears with Mars on the evening of August 8 and morning of August 9.

Earth passes between Mars and the sun on October 13, 2020.

At this hour Jupiter and Saturn are below the horizon in the southwest.  In the hours following sunset, look for them in the southern sky.

Here is a daily summary about the planets during August.

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2020, August 4: Jupiter, Saturn Bright Evening Stars

 

Jupiter and Saturn, August 4, 2020
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.

2020, August 11-12: Peak Perseid Meteors

Meteor Shower
During a meteor shower, shooting stars seem to originate from one spot in the sky. (NASA Photo)

The Perseid Meteor shower peaks on the night of August 11-12, but it is dimmed by a thick waning crescent moon. Even with the moon’s presence, bright meteors are visible.

by Jeffrey L. Hunt

The Perseid Meteor Shower is long-considered the best shower of the year observed from the northern hemisphere.  Other showers may have higher rates, but warm weather and the high elevation of the shower’s radiant before sunrise, as seen from mid-northern latitudes, promises good views.

Perseus is low in the northeast as the sky darkens after sunset.  It is between the bright star Capella and the “W” of Cassiopeia. As the night progresses the constellation and the radiant rise higher into the sky. As morning twilight begins, about two hours before sunrise, Perseus is about two-thirds of the way up in the sky above the northeast horizon.

The shower is from the dust and debris that was liberated by the sun’s energy from Comet Swift-Tuttle (officially known as 109P/Comet Swift-Tuttle). These dabs revolve around the sun, like the planets, but they are scattered along the highly-elongated comet orbit.  Each August, our planet passes through the tiny fragments as they revolve around the sun. High in the sky, the particles vaporize and leave a flash of light in the sky – a shooting star, a meteor.  Like driving through a snowstorm, the meteors emerge from a single point in the sky and the are visible anywhere in the sky.

Unlike random (sporadic) meteors, the Perseids can be traced back to their spot of their origin (radiant).  When you see a possible Perseid, literally follow the trail in the opposite direction.  If it points to Perseus, then it’s likely from the shower.  Sporadic meteors originate from anywhere in the sky.

Official rates of the shower range to 100 meteors per hour when the radiant is highest in the sky.  It is not possible for a single observer to see one meteor or so every minute. A single human’s eyes do not have a large enough field of vision to see the entire sky, and humans have a brightness perception limit.  So, the projected rate is 100 meteors per hour across the entire sky at all brightness levels, even those beyond human perception.  To watch the entire sky, five observers are needed, one to look above each cardinal direction and a fifth to look overhead.

Two other factors play a role: On the peak morning, the moon’s phase is 43% illuminated, bright enough to cast shadows on the ground. The moon is brighter on the days leading up to August 12. This reduces the number by 30% or more.  City lights reduces the number by 50%. So, in the city, about 35 meteors per hour might be visible.  Divide that number by the five observers need to monitor the sky.  A single observer, in town might see 6-7 meteors per hour, perhaps double that in a dark location. This is worth the look, but patience is needed to see several Perseid meteors.

In these days of social distancing, a quintet of observers separated in a backyard, provides interesting meteor observing, but likely before you know it somebody will be snoring!