Archive for month: October, 2021

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

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

• Comet Journals

Comet 67P/Churyumov-Gerasimenko (2021) is about 9th magnitude and moves through Taurus to Gemini in October and will reach perihelion on November 3. It will be closest to Earth on November 12. Comet 4P/Faye moves from Taurus to Orion and Gemini at 10th magnitude in October. Faye passed through perihelion on September 8 and will be closest to Earth in December. Comet 6P/d’Arrest (2021) moves through Sagittarius in October. It was closest to Earth in August and passed perihelion on September 17, reaching magnitude 9. 

• Mars Landers

After successfully collecting its first core sample on Sept. 3, Perseverance Rover made a successful attempt to drill and extract a second rock core from the volcanic rock named Rochette on top of the ridge nicknamed Citadelle in Jezero Crater on Sept. 8. Pore fillings in Rochette indicate that it was subjected to alteration from saline water after it was formed.

This summer’s attempt to clear dust from the InSight Lander’s solar panels was able to allow continued powering of the seismometer which recorded marsquakes of magnitude 4.1 and 4.2 on August 25. On September 18, another 4.2 tremblor occurred. Distances to the epicenters of the three quakes ranged from 575 to 5280 miles. None were located in the Cerberus Fossae region (distance ~1000 miles) in which all the earlier quakes occurred, indicating that crustal movements are widespread on Mars. The Curiosity Rover is following a notch as it climbs Mt. Sharp to an area dominated by salty sulfate minerals. The rover conducted its 33rd drilling in the floor of the notch on Sept. 7, then spent the next two weeks analyzing the drilling samples and measuring  the  environmental characteristics of the area. On the 22nd, it resumed ascent to reach a nodular area in a slightly younger rock layer before shutting systems down for the ensuing solar conjunction. Mars will be on the other side of the Sun which will interfere with radio communication. 

• Meteor Showers

October Meteor showers include the Camelepardalids, Draconids, Epsilon Geminids, Orionids, and Leo Minorids. All but the Draconids and Orionids are minor showers that will produce fewer than 10 meteors per hour in dark skies unpolluted by stray light. The Draconids can sporadically storm but are expected to be minor this year.

October 8: Draconids. Active Oct. 6-Oct 10. Radiant 17h28m +54°. ZHR 0 to storm. 20 km/sec. Waxing Crescent Moon. Progenitor:  Comet Giacobini-Zinner. 

October 18: Epsilon Geminids. Active Oct. 14-Oct. 27. Radiant 6h48m +27°. ZHR 2. 66 km/sec. Waxing Gibbous Moon. Progenitor: Comet C/1964 N1 (Ikeya). 

October 21: Orionids. Active Oct. 2-Nov. 2. Radiant 6h20m +16°. ZHR 20. 66 km/sec. Waning Gibbous Moon. Progenitor: Halley’s Comet. 

• Planet Plotting

Neptune (+7.8) rises in late afternoon in Aquarius and Uranus (+5.7) in Aries rises slightly more than 3 hours later. Both set in the early morning in October. Mars (+1.7), in Virgo, is immersed in the setting Sun’s glow as it approaches Solar Conjunction with the Sun the 8th and will appear in the morning sky in the last part of October.

Venus (-4.1 to -4.3) in Ophiuchus and Mercury (+2.1 to -0.8) in Virgo are in the western-southwestern sky after sunset in early October. Mercury is buried in the glow of sunset on the 1st and reaches Inferior Conjunction with the Sun on the 9th. Venus (-3.9 to -4.1) grows brighter each evening and reaches Maximum Eastern Elongation on the 29th. After the 9th, Mercury will move to the morning sky and will gradually rise out of the glow of sunrise in late October. Jupiter (-2.6 to -2.3) and Saturn (+0.5 to +0.6) in Capricornus rise in the eastern sky in the late morning and are best viewed in the early evening when highest in the southern sky. They set in the late evening.

October’s waxing crescent Moon appears to pass the evening planets – Mars, Mercury, and Venus – from the 6th through the 9th. The first two passages will be very difficult to see on the 6th when the crescent Moon, Mars, and Mercury appear too close to the Sun. The waxing gibbous Moon will appear to pass the morning planets – Saturn, Jupiter, and Neptune – from the 14th through the 17th. The waning gibbous Moon will pass Uranus on the 21st.

Planet	Constellation(s)	Magnitude	Planet Passages	Time	Date
Sun	Libra	-26.5	New Moon	7:08AM EDT	10/6
Mercury	Virgo	2.1 to.-0.8	Inferior Conjunction Mars, 2.41°NE Max West Elongation	Noon EDT 1:00AM EDT 1:00AM EDT	10/9 10/10 10/25
Venus	Ophiuchus	-4.1 to -4.3	Max East Elongation	5:00PM EDT	10/29
Mars	Virgo	1.7	Solar Conjunction Mercury, 2.41°SW	Midnight EDT 1:00AM EDT	10/8 10/10
Jupiter	Capricornus	-2.6 to -2.3
Saturn	Capricornus	+0.5 to +0.6
Uranus	Aries	5.7
Neptune	Aquarius	7.8

• October Moon

October’s New Moon on the 6th at 7:05AM EDT introduces Lunation 1222 which ends with November’s New Moon, 29.31 days later on the 4th at 5:14PM EDT. October 20 at 10:56AM EDT is marked by a Full Moon, commonly known as “Hunter’s Moon.” The name was apparently adopted from Native Americans in colonial times. In Medieval England, it was the “Blood” Moon.” Chinese call it “Kindly” Moon and for Celts it was “Harvest or Snow” Moon. 

The “Hunter’s Moon” is the full moon after the September Harvest Moon. At this time of year, the path of rising Moon is at a low angle to the horizon. The Full Moon rises slowly and moves southward above the eastern horizon, casting light over stubble in harvested corn fields, exposing game animals hiding places to hunters.

Of 13 Grandmother Moons each year, the 10th Moon is “Binaakwe Giizi” (Bi-nah-kway) – the Falling Leaves Moon for Anishinaabe (Odawa & Ojibwe) people. Cultural teachings explain the cycle of life and nature for the 10th Moon as “the leaves turn to breathtaking shades of red, orange, yellow, and gold before falling to the ground. It’s the grandest of spectacles to honor Mother Earth, and a powerful reminder of all the miracles in creation that sustain us and all our relations such as the animals and plants. Falling Leaves Moon is a time to honor, and give thanks.”

Lunar Perigee distance (minimum lunar distance) is 225797.6 miles on the 8th at 1:28PM EDT. Lunar Apogee (maximum lunar distance) is on October 24 at Noon EDT. The Moon will be at a distance of 252037.4 miles.

Planet	Constellation	Magnitude	Moon Passages	Moon Phase	Moon Age
Sun	Virgo	-26.8	7:05AM EDT, 10/6	New	0 Days
Mercury	Virgo	3.5	6.2°SSW, 7:00PM EDT, 10/6	Waxing Crescent	0.50 Days
Venus	Scorpius	-4.1	2.74°SSW, 5:00PM EDT, 10/9	Waxing Crescent	3.30 Days
Mars	Virgo	1.7	3.2°SSW, 9:00AM EDT, 10/6	Waxing Crescent t	0.08 Days
Jupiter	Capricornus	-2.5	4.0°NNW, 9:00AM EDT, 10/15	Waxing Gibbous	8.97 Days
Saturn	Capricornus	0.5	3.8°NNW, 5:00AM EDT, 10/14	Waxing Gibbous	7.80 Days
Uranus	Aries	5.7	1.24°NNW, 7:00PM EDT, 10/21	Waning Gibbous	15.38 Days
Neptune	Aquarius	7.8	3.7°NNW, 2:00PM EDT, 10/17	Waxing Gibbous	11.17 Days