August Skies – by Dick Cookman

/in /by

Highlights:  Comet Journal, Martian Landers, Meteor Showers, Planet Plotting, August Moon 

Focus Constellations: Ursa Minor, Draco, Cepheus, Cassiopeia, Perseus, Camelopardalis, Ursa Major, Canes Venatici, Coma Berenices, Bootes, Corona Borealis, Hercules, Lyra, Cygnus

  • Comet Journals

C/2017 K2 (PanSTARRS) is the brightest August comet at 8th magnitude. It is moving southward below Ophiuchus and will be in Scorpius by month’s end. It was closest to Earth at 168 million miles on July 14, 2022 and will reach perihelion on December 19, 2022. It is expected to remain at its current brightness until November when it moves into southern hemisphere skies. C/2022 E3 (ZTF) is a 12th magnitude comet between Hercules and Bootes. What distinguishes it from numerous other current 11th and 12th magnitude comets is the possibility that it may reach naked eye visibility as a Christmas comet and reach maximum brilliance when at perihelion in early January.

  • Mars Landers

The Perseverance rover, at the foot of a delta on the edge of Jezero Crater, confirmed long distance observations made when it first landed about one mile away from its current location. Close up images reveal sedimentary structures and sediments consistent with deltaic deposition. Furthermore, large one meter boulders in the uppermost layers indicate that a long period of gradual deposition by a small river leading into the lake that filled the crater was followed by a period of flash flooding before the lake dried up. Finer grain layers below the flash flood deposits provide ideal targets for sampling for organic material which drifted down the river and settled into the delta.  

The Insight rover seismometer received an extended lease on life into the autumn when mission scientists decided that ~1500 marsquakes so far recorded justified further investigation into possible magma movement in the mantle.

For the past 10 years, the Curiosity rover traveled across the Martian terrain, looking for clues to the planet’s potentially habitable past. Gizmodo notes that “the car-sized robot drove through a transition zone, going from an area that may have once hosted lakes on the surface to one that signifies drier conditions for the Red Planet. NASA’s Curiosity rover observed the change higher up on the 3.4-mile-tall (5-kilometer) Mount Sharp which is the central peak in Mars’ Gale Crater, where the rover is exploring for signs of ancient water. At its base, Curiosity collected evidence for clay minerals that formed from lakes and streams that once ran through the crater. But higher up on the mountain, those streams had seemingly dried up, leaving sulfate rich sand dunes above lake sediments.”

Meteor Showers

August is the month of the renowned Perseids, the reliable meteor shower emanating from Perseus. Predawn hours provide the most meteors/hour because observers are on the leading face of the Earth as it orbits into the meteor stream. Mornings preceding the peak are best viewing because the almost full moon (and its glare) sets before sunrise. Each day before full moon provides an extra hour of dark sky.

August 12: Perseids. Active July 17 – Aug. 24, Radiant 3h13m +58°, ZHR 50+, 59km/sec. Waning Gibbous Moon. Progenitor: Comet 109P/Swift-Tuttle. 

August 17: Kappa Cygnids. Active August 6 – August 20, Radiant 19h13m +53°, ZHR 5, 23km/sec. Waning Gibbous Moon. Progenitor: Comet ?.

    • Planet Plottings 

The pre-dawn sky in August displays a six planet lineup in the southern sky. On July 31, Saturn (+0.4 to +0.3) in Capricornus, the leader, rises in the east about 9PM EDT followed by four more planets before 3:00AM EDT on the 1st. Venus (-3.8) in Gemini finally makes its appearance two hours before sunrise when the six planets span the sky. From Venus near the east-northeast horizon look to the south to Uranus (+5.8 to +5.7) and Mars (+0.2 to -0.1) slightly higher in the east in Aries, followed by Jupiter (-2.5 to -2.7) in Cetus, Neptune (+7.8) in Pisces and, finally, Saturn low in the west-southwest. At 5:00AM EDT on the 1st, Mars and Uranus will be within less than 1.5 degrees of one another in Aries. Saturn reaches opposition on the 14th when it will be visible all night and is best observed at midnight in the south. Mercury (-0.5 to +0.5) is the only planet restricted to evening skies in August as it moves through Leo and into Virgo and sets slightly more than an hour after sunset. It reaches maximum eastern elongation at noon on the 27th. 

Planet

Constellation(s)

Magnitude

Planet Passages

Time

Date

Sun

Cancer, Leo

-26.5

New Moon

4:17AM EDT

8/27

Mercury

Leo, Virgo

-0.5 to +0.5

Greatest East Elongation (27°)

Noon EDT

8/27

Venus

Gemini, Leo

-3.8

Mars

Aries, Taurus

+0.2 to -0.1

Uranus, 1.4°N

5:00AM EDT

8/1

Jupiter

Cetus

-2.5 to -2.7

Saturn

Capricornus

+0.4 to +0.3

Opposition

1:00PM EDT

8/14

Uranus

Aries

5.8

Mars, 1.4°S

5:00AM EDT

8/1

Neptune

Pisces, Aquarius

7.8
    • August Moon

The New Moon of August in Leo on the 27th at 4:17AM EDT is the start of Lunation 1233 which ends 29.57 days later with the New Moon of September in Virgo on the 25th at 5:53PM EDT. August’s Full Moon in Capricornus is on the 11th at 9:36PM EDT. It is called The “Grain or Green Corn Moon”. It was the “Corn Moon” in Medieval England. Celts called it “Dispute Moon”, and in China, it is the “Harvest Moon”. Colonial Americans called it “Dog Day’s Moon”, a term descended from ancient Egyptians who invented the solar calendar which starts the year with the helical rising (rising with the Sun) of the Dog Star— Sirius. This preceded the annual flood which fertilized fields and signaled the start of planting season.
Of 13 Grandmother Moons during each year, Anishnaabe (Odawa and Ojibwe) first people recognize the 8th Moon as Manoominike-giizis (Ricing Moon). According to the folks at Earth Haven Farm in Ontario, this Grandmother Moon is the Thimbleberry/Strawberry or Sturgeon Moon. The cultural teaching explaining the cycle of life and nature for the Thimbleberry Moon of Creation is that: “it’s purpose is to protect the Sacred Circle of Life by allowing us to recognize and understand the teachings that come from the Spirit World.”
Lunar Perigee distance (minimum lunar distance) is 223,587 mi. (56.42 Earth radiil) on the 10th at 1:09PM EDT, only 32.27 hours before Full Moon. This means that we have a large and bright SUPERMOON, not as spectacular as those in June and July, but still very impressive. Lunar Apogee (maximum lunar distance) in August is on the 26th at 6:22AM EDT, when the Moon will be at a distance of 251,915 mi. (63.57 Earth radii). The waxing gibbous Moon appears to pass Saturn on the 11th. The waning gibbous Moon passes Neptune on the 14th, Jupiter on the 15th, and Uranus on the 18th. The waning crescent Moon passes Mars on the 19th, and Venus on the 25th. After New Moon, the waxing crescent passes Mercury on the 29th.

Planet

Constellation

Magnitude

Moon Passages

Moon Phase

Moon Age
Sun Leo

-26.8

 4:17AM EDT, 8/27 New 0 Days
Mercury Virgo

0.4

 7.0°N, 7:00AM EDT, 8/29 Waxing Crescent 3.55 Days
Venus Cancer

-3.8

 4.0°N, 5:00PM EDT, 8/25 Waning Crescent 28.98 Days
Mars Taurus

0.0

 3.0°N, 8:00AM EDT, 8/19 Waning Crescent 23.15 Days
Jupiter Cetus

-2.6

 2.0°S, 6:00AM EDT, 8/15 Waning Gibbous 19.07 Days
Saturn Capricornus

0.3

 4.0°S, Midnight EDT, 8/11 Waxing Gibbous 14.82 Days
Uranus Aries

5.7

 0.6°N, 11:00AM EDT, 8/18 Waning Gibbous 22.28 Days
Neptune Pisces

7.8

 3.0° S, 6:00AM EDT, 8/14 Waning Gibbous 18.07 Days