August Skies by Dick Cookman

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

Focus Constellations: Ursa Major, Ursa Minor, Draco, Cepheus, Cassiopeia, Camelopardalis, Perseus, Andromeda,Pegasus, Cygnus, Aquila, Lyra, Hercules

  • Comet Journals 

Comets C/2023 E1 (ATLAS) sails through Cepheus, Cygnus, and Pegasus at 10/9th magnitude in August. It passed perihelion on July 1 and be closest to Earth on August 18. C/2021 T4 Lemmon is an Oort Belt comet. It is in Taurus and was closest to Earth on July 20 and passed perihelion on the 31st. It will enter southern hemisphere skies in Eridanus and move eastward into Çetus in August.

  • Mars Landers

Olympus Mons, 12.5 miles high, located on the Tharsis Rise on Mars, a volcanic province larger than Arizona, it is the largest volcano in the solar system. Most of it was formed over 2.5 billion years ago, but more recent activity is suspected. Hilldenbrand, et al suggests: “Conspicuous slope breaks at the top of the main basal escarpment surrounding Olympus Mons are here interpreted as paleo-shorelines around a former volcanic island. Similar features at Alba Mons further support the existence of an early ocean occupying the northern plains of Mars along the NW edge of the Tharsis region. The proposed shorelines stand much higher than previously reported late Noachian sea levels, suggesting later high-magnitude regional uplift in response to deep internal forcing….” (Hilldenbrand et al. Earth and Planetary Letters, vol. 619.1 October, 2023, 118302). Evidence for ancient shorelines at the top of a 3.5 mile high escarpment on the volcano’s perimeter? Shorelines of an ocean that may have filled the northern lowlands of Mars?

Our little rovers reveal ancient organic molecules dispersed over Mars, and provide evidence of ancient water bodies and and now an ocean? Mars has ground ice, water in icecaps, and lots of cold, dry, eroded and desiccated land. What happened to Earths’ little brother?

  • Meteor Showers

Of the six meteor showers in August, four are minor, one moderate, and the Perseids are the best! The minor showers include the southern Iota Aquarids (8/4), northern Delta Aquarids (8/8), Kappa Cygnids (8/17), and northern Iota Aquarids (8/19). The Perseids (8/13) and the moderate Alpha Aurigids (8/31) are:

August 13, 4AM: Perseids. Active July 17- August 24. Radiant 03h04m +57°. ZHR 120 t0 160. 59 km/sec. Very Favorable –  Perseus high in eastern sky, Waning Crescent Moon. Progenitor: Comet Swift-Tuttle.

Aug 31/Sept. 1: Alpha Aurigids. Active Aug 25 – September 5.. Radiant 05h36m +42°. ZHR 10. 66 km/sec. Unfavorable, Waning Gibbous Moon. Progenitor: Comet Kiess (C/1911 N1).

  • Planet Plottings

In August, Venus (-4.1 to -4.3) moves from Leo to Cancer where it has its inferior conjunction with the Sun on the 13th, right after the Perseid Meteor shower. It will then pop into eastern morning skies in the last two weeks of August. Crescent Venus can be easily seen at the end of the month when it is 26.5° west of the Sun and 10° above the horizon an hour before sunrise. At the same time, Uranus (+5.8 to +5.7) in Aries, can be seen with binoculars scintillating in Aries high in the southeast, slightly below and east of Jupiter (-2.2 to -2.4). Neptune (+7.8) in Pisces, and Saturn (+.6 to +0.4) in Aquarius are in the southwestern sky and can be seen in the eastern sky in the evening. August provides the best viewing of Saturn in 2023 because it will be at opposition on the 27th. 

In early August, Mars (+1.8) and Mercury (+0.2 to +2.8) are just above the western horizon in Leo in the afterglow of sunset. Mars is higher but harder to find because it is much dimmer. After Mercury’s maximum eastern elongation of 27° from the Sun on the 9th, both planets become harder to find as they drop lower in the western sky after sunset.

The waning gibbous Moon passes Saturn on the 6th and Neptune on the 8th and the waning crescent passes Jupiter and Uranus on the 11th and 12th. The waxing crescent passes Mercury on the 19th, and Mars and Venus on the 20th.

Planet

Constellation(s)

Magnitude

Planet Passages

Time

Date

Sun

Cancer, Leo

-26.5

New Moon

5:38AM EDT

8/16

Mercury

Leo

+0.2 to +2.8

Max. East Elongation

10:00AM EDT

8/9

Venus

Leo, Cancer

-4.1 to -4.3

Inferior Conjunction

7:00AM EDT

8/13

Mars

Leo, Virgo

1.8

Jupiter

Aries

-2.2 to -2.4

Saturn

Aquarius

+0.6 to +0.4

Opposition

4:00AM EDT

8/27

Uranus

Aries

+5.8 to +5.7

Neptune

Pisces

7.8

  • August Moon

The New Moon of August is in Leo on the 16th at 5:38AM EDT. The New Moon marks the start of Lunation 1245 which ends 29.67 days later with the New Moon of September at the boundary of Leo and Virgo on the 14th at 9:40AM EDT. There are two Full Moons in August. Both are “Supermoons” because each occurs near perigee when the Moon is closest to Earth and presents its largest image. The Full Moon on the 1st occurs at 2:32PM in Capricornus, 11.3 hrs before perigee. It is called the Sturgeon, Green Corn, or Grain Moon. The Full Moon on the 30th in Aquarius is the brightest of 2023 and occurs at 9:36PM EDT, 9.7 hours after perigee. As the 2nd Full Moon in the month, it is also called a “Blue Moon”. The August Full Moon was called the “Corn Moon” in Medieval England and for Celts it was the “Dispute Moon”. In China, it is the “Harvest Moon” and Colonial Americans called it “Dog Day’s Moon”. Anishnaabe (Odawa and Ojibwe) first people recognize the years’ 8th Moon as “Manoominike-giizis” (Ricing Moon). 

Ontario ’s Earth Haven Farm presents cultural teachings explaining the cycle of life and nature of August’s Grandmother Moon of Creation: “The eighth moon of Creation is the Thimbleberry Moon, when we honor the Thimbleberry which produces an abundance of fruit once every three years. It was one of the first plants put on Mother Earth, and its purpose is to protect the Sacred Circle of Life by allowing us to recognize and understand the teachings that come from the Spirit World.” 

The first Lunar perigee in August is on the 2nd. The Moon is at 222,022 mi. (56.03 Earth radii) at 1:52AM EDT. The 2nd at 11:54AM EDT on the 30th is at 221,942 mi. (56.00 Earth radiil). Lunar Apogee (maximum lunar distance) is on August 16 at 5:38AM EDT when the Moon’s is at 252,671 mi. (63.75 Earth radii).                                                                                                                           

A waning gibbous Moon passes Saturn on the 3rd, Neptune on the 4th, Jupiter and Uranus on the 8th. A waning crescent passes Venus on the 15th, and a waxing crescent passes Mercury and Mars on the 18th.

Planet

Constellation

Magnitude

Moon Passages

Moon Phase

Moon Age

Sun Gemini

-26.8

5:38AM EDT, 8/16 New 0 Days
Mercury Leo

0.8

7.0°N, 7:00AM EDT, 8/18 Waxing Crescent 2.06 Days
Venus Cancer

-3.9

13.0°N, Noon EDT, 8/15 Waning Crescent 28.60 Days
Mars Virgo

1.8

2.0°N, 7:00PM EDT, 8/18 Waxing Crescent 2.56 Days
Jupiter Aries

-2.3

3.0°N, 6:00AM EDT, 8/8 Waning Gibbous 21.64 Days
Saturn Aquarius

0.6

2.0°S, 6:00AM EDT, 8/3 Waning Gibbous 16.64 Days
Uranus Aries

5.8

3.0°N, 9:00PM EDT, 8/8 Waning Gibbous 22.27 Days
Neptune Pisces

7.8

1.5° S, 6:00PM EDT, 8/4 Waning Gibbous 18.14 Days