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January 2020 Skies

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January Skies

by Dick Cookman


Highlights: Comet Journal, Martian Landers, Meteor Showers, Longest Night?, Planet Plotting, January Moon

Focus Constellations: Pegasus, Pisces, Andromeda, Aries, Perseus, Taurus, Orion, Gemini, Auriga, Cancer, Leo, Camelopardalis, Lynx, Ursa Major, Draco, Ursa Minor, Cepheus, Cassiopeia

Comet Journals

Comet C/2017 T2 PanSTARRS is a 9th magnitude comet moving through Perseus in January. It is a long period comet which rose out of the Oort Cloud below the solar system on an orbit tilted at over 60 degrees to the solar system plane. It crossed the plane into northern skies in August and reached closest proximity to Earth on Dec. 29. Best viewing will be in the latter half of the month when the Moon is waning and the Milky Way provides a background for the slowly moving comet. On the 26th and 27th, it will pass north of Perseus’ double cluster and may brighten to 8th magnitude in February as it approaches perihelion (closest to the Sun) on May 4, 2020. It will then drop back through the plane of the solar system in September and embark on its long journey back to the Oort Cloud.

Mars Landers

The Insight lander’s “mole” is digging again as it attempts to place the Heat Flow and Physics Properties Package (HP3) in position at a depth of 16 feet to accurately measure heat flow and seismic activity! After it became lodged at a very shallow depth and then popped out of the hole in October, initial success occurred on Nov. 21 when NASA announced that the probe had drilled another 1.25”. On Dec. 16, the agency said that the mole was continuing to drill properly as it drilled another 2.5” deeper. The seismometer team has also determined the origin of the May 22 and July 25 marsquakes which were traced to an active fault zone in Cerberus Fossae.The Curiosity rover is in Glen Torridon, the clay-bearing unit in the valley adjacent to Vera Rubin Ridge on 16,404 foot Mt. Sharp at the center of Gale Crater, the ancient remnant of a massive impact. Over the course of three Mars years (or nearly six Earth years) an instrument in the Sample Analysis at Mars (SAM) portable chemistry lab inside NASA’s Curiosity rover sampled the air of Gale Crater and analyzed its composition. The results SAM spit out confirmed the makeup of the Martian atmosphere at the surface: 95% by volume of carbon dioxide (CO2), 2.6% molecular nitrogen (N2), 1.9% argon (Ar), 0.16% molecular oxygen (O2), and 0.06% carbon monoxide (CO). It also revealed how the molecules in the Martian air mix and circulate with the changes in air pressure throughout the year. These changes are caused when CO2 gas freezes over the poles in the winter, lowering the air pressure across the planet as air is redistributed to maintain pressure equilibrium. When CO2 evaporates in the spring and summer and mixes across Mars, it raises the air pressure.

Scientists found that nitrogen and argon follow a predictable seasonal pattern, waxing and waning in concentration in Gale Crater throughout the year relative to how much CO2 is in the air. Methane (CH4) is also in the air inside the crater in such small quantities (0.00000004% on average) that it’s barely discernable even by the most sensitive instruments on Mars. Still, it’s been measured by SAM’s Tunable Laser Spectrometer. The instrument revealed that while methane rises and falls seasonally, it increases in abundance by about 60% in summer months for inexplicable reasons. They expected oxygen to mimic Argon and Nitrogen, but it didn’t. Instead, the amount of the gas in the air rose throughout spring and summer by as much as 30%, and then dropped back to levels predicted by known chemistry in fall. This pattern repeated each spring, as the amount of oxygen added to the atmosphere varied, implying that something??? caused it to behave like methane.

Meteor Showers, Asteroid Surprises

The Quadrantid Meteor Shower is named after an antiquated constellation, Quadrans Muralis (wall mounted quadrant) in northern Bootes. The shower may be particularly rich this year, possibly rivaling the August Perseids or December Geminids. Its progenitor recently passed through perihelion in September, possibly leaving more debris in the asteroids orbital path. Other showers in January include the Delta Concrids which typically produce less than 5 meteors per hour.

  • January 2: Quadrantids. Active Jan. 1-Jan. 5. Radiant 15h20m +49°. ZHR 120. 41 km/sec. Waxing Crescent Moon. Progenitor: Asteroid (196256) 2003 EH1.
  • January 13: Delta Cancrids. Active an. 1-Jan. 24. Radiant 08h40m +20°. ZHR 4. 28 km/sec. Waning Gibbous Moon. Progenitor: Asteroid 3200 Phaethon.
  • Three near-Earth asteroids passed by on Dec. 30 and 31, and three more will pass on Jan. 2, 4, and 10. None of them were any closer than the Moon.

Longest Night?

The Winter Solstice on December 21st was the longest night of the year for inhabitants of the northern hemisphere. However, the 21st was neither the earliest sunset nor the latest sunrise. If you live on the 40° North parallel, the former was on December 8 and the latter occurs on January 5. They do not coincide with the solstice because Earth has an elliptical orbit and moves most rapidly when closest to the Sun (perihelion) on January 8. Before perihelion, it is speeding up in orbit and after perihelion it slows down. Sunrise and sunset times depend on the changing relationship between orbital speed and rotation rate, thus moving earliest sunset up two weeks near perihelion and delaying latest sunrise a similar amount.

Similarly, the Earth moves slowest when farthest from the Sun at aphelion in early July. The earliest sunrise precedes the Summer solstice by a week and the latest sunset is a week after the solstice.

Planet Plotting

Mercury (-0.9 to -1.2) appears to pass within about 2° of Jupiter (-1.7) and Saturn (+0.6) in Sagittarius on January 2 and 12 respectively and Venus (-4.0), and Neptune (-7.9) are separated by less than 0.1° as early evening planets in Aquarius on January 27. The Mercury/Jupiter near conjunction may be visible immediately before sunrise near the southwestern horizon and the Mercury/Saturn event will be buried in glow of sunrise as Saturn approaches solar conjunction on the 13th.

Mars (+1.6 to +1.4) in Libra and Ophiuchus joins Jupiter as a predawn planet in January. Mars brightens during the month and rises higher in the early morning sky because Earth is orbiting closer to the red planet and will catch up on the October opposition. Jupiter is barely above the predawn horizon on the 1st and rises higher in the sky during January.

Uranus (+5.7 to +5.8) in Aries, Neptune (+7.9) in Aquarius, Venus (-3.9 to -4.0) in Capricornus and Aquarius and Mercury (-0.8 to -0.9) in Sagittarius and Capricornus are evening planets. Mercury moves out of the morning sky in early January before it reaches superior conjunction with the Sun on the 10th, and into the evening sky late in the month when Venus and Neptune are in conjunction. It can be found between Venus and the southwestern horizon in the early evening and sets slightly less than 2 hours before Venus.

The waxing gibbous Moon is 5.0° from Uranus at 1:00PM EST on the 4th. The waning crescent Moon is 2.0° from Mars on the 20th, 0.4° from Jupiter on the 22nd, and 1.47° from Saturn on the 23rd. The waxing crescent Moon passes 1.33° from Mercury at 3:00PM EST on the 25th, 4.0° from Neptune at 1:00AM EST and 4.0° from Venus at 2:00AM EST on the 28th, and is 5.0° from Uranus at 10:00PM EST on the 31st.

PlanetConstellation(s)MagnitudePlanet PassagesTime, Date
SunSagittarius, Capricornus-26.8New Moon4:42PM EST, 1/24
MercurySagittarius, Capricornus-0.8 to -0.9Jupiter, 1.5°N
Superior Conjunction
Saturn, 2.04°N
11:00AM EST, 1/2
10:00AM EST, 1/10
5:00AM EST, 1/12
VenusCapricornus, Aquarius-3.9 to -4.0Neptune, 0.08°N2:00PM EST, 1/27
MarsLibra, Ophiuchus+1.6 to +1.4  
JupiterSagittarius-1.7Mercury, 2.04°S11:00AM EST, 1/12
SaturnSagittarius+0.5 to +0.65Mercury, 1.8°S
Solar Conjunction
Midnight EST,1/10
10:00AM EST, 1/13
UranusAries+5.7 to +5.8  
NeptuneAquarius+7.9Venus, 0.08°S2:00PM EST, 1/27

January Moon

The New Moon on January 24 at 4:42PM EST is the beginning of Lunation 1201 which ends 29.72 days later with the New Moon on February 23 at 10:32AM EST. The Full Moon of January on the 10th at 2:21PM EST presents a penumbral eclipse for observers in Asia, Australia, Europe, and Africa. Commonly known as the “Moon After Yule” or “Old Moon”, it was called the “Winter Moon” in colonial times and in Medieval England it was the “Wolf Moon.” Celts named it the “Quite Moon” and the Chinese call it the “Holiday Moon”. Anishinaabe (Odawa and Ojibwe) people recognize it as ““Manidoo-gizis (Spirit Moon).

Lunar Apogee (maximum orbital distance) occurs on the 1st at 8:30PM EST when the Moon is at 251,394 miles (63.43 Earth radii). Perigee occurs on the 13th at 3:21PM EST when the Moon is at a distance of 227,396 miles (57.38 Earth radii). Another apogee occurs on the 29th at 4:27PM EST when the Moon’s distance is 251,899 miles (63.56 Earth radii).

PlanetConstellationMagnitudeMoon PassagesMoon Phase, Moon Age
SunCapricornus-26.84:42PM EST, 1/24New..0 days
MercuryCapricornus-1.01.33°SE, 3:00PM EST, 1/25Waxing Crescent..1.43 days
VenusAquarius-4.04.0°S, 2:00AM EST, 1/28Waxing Crescent..3.39 days
MarsOphuiuchus+1.42.0°N, 2:00PM EST, 1/20Waning Crescent..25.57 days
JupiterSagittarius-1.70.4°S, 10:00PM EST, 1/22Waning Crescent..26.99 days
SaturnSagittarius+0.61.47°SE, 10:00PM EST, 1/23Waning Crescent..28.91 days
UranusAries+5.85.0°S, 1:00PM EST, 1/4
5.0°S, 10:00PM EST, 1/31
Waxing Gibbous..9.53 days
Waxing Crescent..7.22 days
NeptuneAquarius+7.94.0°S, 1:00AM EST, 1/28Waxing Crescent..3.35 days

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