January 2015 – Skies News

12/31/2014
January Skies by Dick Cookman

Highlights: Comet Journal, Martian Landers, Meteor Showers, Winter Solstice, Planet Plotting, January Moon

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

Comet Journal

C/2012 K1 (PanSTARRS) is at 6th magnitude in southern hemisphere skies out of sight of observers in northern hemisphere mid-latitudes throughout 2015 as it moves toward the outer Solar System and diminishes in brightness.

Comet C/2014 Q2 (Lovejoy) at 5th magnitude near Lepus was one of the brightest comets of 2014. It will reach 4th magnitude and may be visible to the naked eye in dark skies when it passes within 0.469 AU (43,600,000 mi) from Earth in Eridanus on January 7th. Best viewing will be in the early evening before the rising of the waning Gibbous Moon when the comet is southwest of the belt of Orion. It will maintain its brightness until the 4th week of January when it passes Aries. By the end of the month it will decrease to 5th magnitude as it retreats from Earth and approaches slightly closer to the Sun. It will pass through perihelion northeast of Triangulum on the 30th and will continue to rise higher in northern skies, ascending above the plane of the solar system on its 5000 year return journey to the Oort Belt.

Mars Landers

Opportunity continued southward on its journey to reach Marathon Valley where satellites discovered evidence for abundant clay minerals. The drive proceeded in mid – November with segments on Nov. 13 – 19 (Sols 3844-3846) producing a total of 456 feet of travel. The last 10 days of November were devoted to examination of a nearby light colored exposed bedrock outcrop with multiple imaging instruments. On the 28th (Sol 3856), the Flash memory issue plaguing the rover during previous weeks resurfaced with an amnesia event and a reboot. After the reboot, the rover was no longer under sequence control and was unable to mount the Flash (non-volatile) memory. The rover was restored to normal sequence operation on Sol 3859 (Dec. 1, 2014), but the Flash file system remained unavailable. Preparation for reformatting of the Flash memory began on Sol 3862 (Dec. 4, 2014). Although the rover’s operation improved immediately after the reformat, Flash behavior quickly deteriorated. Opportunity experienced a series of resets on Sols 3864 and 3865 (Dec. 6 and Dec. 7, 2014). A decision was then made to operate the rover without the use of Flash memory until another fix can be implemented. On Sol 3866 (Dec. 8, 2014), the rover was booted without using Flash (data products were stored in volatile RAM memory) and all the fault conditions were cleared. Opportunity performed light science activities in preparation for driving on Sol 3867 (Dec. 9, 2014). Mission scientists are developing a long term strategy to mask off the troubled sector of Flash and use just the rest of the Flash file system. Solar energy is averaging about 500 watt hours per day. Total odometry on Mars for the rover is 25.73 miles (41.42 kilometers).

Curiosity’s observations at 3 mile high Mt. Sharp at the center of Gale Crater, an impact basin about 96 miles (154 kilometers) in diameter, indicate that the rock layers comprising Mount Sharp are composed of sediments laid down in a large lake which filled the gigantic crater. The layers alternate from lake to river and wind deposits and indicate that repeated filling and evaporation events transpired during the accumulation of the layers. More recent erosion removed most of the rock that filled the crater leaving Mt. Sharp as an exposed remnant of the once pervasive layers.

Meteor Showers

The Quadrantid meteor shower which peaks on January 4th will have major competition from the glare of the Full Moon. The shower is named after a constellation no longer recognized. It could be called the Northern Bootid shower because the radiant of the meteors is in northern Bootes near the end of the handle of the Big Dipper. Bootes rises in the northeast about 11PM when the Moon is in the southern sky. When the Moon sets at dawn, the radiant will be high in the southeastern sky. Although the meteor shower has displayed over 200 meteors per hour and averages over 100 meteors per hour in dark skies, moon glare will limit it to a fraction of that amount.

Comet 96P/Machholtz and Asteroid 2003 EH1 are the likely sources of the meteors even though the comet’s orbit does not match that of the meteors, possibly due to recent perturbations of the comet when passing Jupiter. The comet and asteroid orbit the Sun in about 5 years. The former last visited the inner Solar System in 2012, the latter in March of 2014.

Winter Solstice

Although the solstice on December 21st was the shortest day and longest night, it provided neither the earliest sunset nor the latest sunrise of the year. The former was on Dec. 8, 2014 at 4:35PM EST at latitude 40° N and the latter occurs this year on Jan. 4th at 7:22AM EST at the same latitude. The clock time for rising and setting of the Sun varies throughout the year and is influenced by latitude. Winter days are shorter than summer days and the difference is more extreme for high latitude locations. Clock time for solar rising and setting and Solar Noon is also influenced by the variation in speed that the Earth experiences as it revolves in its elliptical orbit about the Sun. When closest to the Sun at perihelion (2AM EST on Jan. 4th, 2015) the Earth races at its maximum rate and when most distant from the Sun at aphelion (early July) the Earth ambles along its orbit at its slowest speed. This variation affects the timing of Solar Noon and of sunrise and sunset times. Due to Earth’s motion in orbit, the time between consecutive solar noons when the Sun is on the local meridian averages about 4 minutes longer than the time required to turn 360°.

When traveling fastest at perihelion, the Earth has to rotate farther each day to make up for this motion making the Solar day slightly more than 4 minutes longer than the time required to rotate 360°. At aphelion it is slightly less. This deviation from the 4 minute average is referred to as “sunfast” or “sunslow” and is summarized in the “Equation of Time”. The graph of this equation is known as the “Analemma”.

A photographic film image of this may be created by photographing the setting Sun on the Winter Solstice, then making multiple exposures through the year without advancing the film. The resulting figure 8 pattern is often reproduced somewhere in the Pacific Ocean on Earth globes. The east-west deviation from the meridian connecting the top and bottom of the figure 8 is a portrait of the “Equation of Time”, and the north-south variation along the meridian is the yearly change in altitude of the Sun due to the tilt of Earth’s axis.

Planet Plotting

The evening planets of January are Mercury, Venus, Mars, Jupiter, Uranus, and Neptune. In early January, Mercury (-0.8) and Venus (-3.9) are low in the southwestern sky in Sagittarius and move into Capricornus as the month progresses. During the last two weeks of January, Mercury dims to less than magnitude +0.3 and drops into the glow of sunset while Venus rises into Aquarius. Mars (+1.1 to +1.2) moves from Capricornus into Aquarius about 20° above the horizon in the southwestern sky an hour after sunset and sets about 3 hours after the Sun at month’s end. Jupiter (-2.4) rises about 8PM EST in Leo and is visible throughout the night. Neptune (+7.9 in Aquarius) and Uranus (+5.8 in Pisces) are visible in the south after sunset. Neptune sets between 8PM and 9PM EST and Uranus sets in the late evening.

After passing through solar conjunction in November, Saturn (0.6) moves into the predawn southeastern sky in Scorpius in early January joining Jupiter which is in the southern sky before dawn. Saturn rises by 3AM EST at month’s end.

Planet……Constellation……Magnitude……Planet Passages

Sun…Sagittarius, Capricornus…….-26.8…..New Moon, ………………………………………………………1/20, 8:14AM EST Mercury..Sagittarius, Capricornus..-0.8 to+5.2 …………………………………………………Max East Elongation …………………………………………………………1/14, 3PM EST …………………………………………………Inferior Conjunction …………………………………………………………1/30, 9AM EST Venus..Sagittarius, Capricornus, Aquarius..-3.9
…………………………………………………Neptune, 1.2°N. …………………………………………………………1/31, 7PM EST Mars……..Capricornus, Aquarius………+1.1 to +1.2
…………………………………………………Neptune, 0.2°N. …………………………………………………………1/19, 4PM EST Jupiter…..Leo…………………..-2.4 to -2.6
Saturn…..Scorpius…………….+0.6 to +0.5
Uranus….Pisces………………..+5.8
Neptune…Aquarius…………..+7.9
…………………………………………………Mars, 0.2°S. …………………………………………………………1/19, 4PM EST
…………………………………………………Venus, 1.2°S. …………………………………………………………1/31, 7PM EST

January Moon

December’s New Moon on the 21st at 8:36 PM EST marked the start of Lunation 1138 which ends 29.48 days later with the New Moon of January on the 20th at 8:14 AM EST.

January’s Full Moon is in Taurus on the 4th at 11:53 PM EST. The horns of Taurus are at the left hand of the Anishnaabe constellation “Beboonkeonini”, the “Wintermaker”, which is centered on modern day Orion. An expert conoeist, the Wintermaker stands astride the celestial equator, his outstretched arms and legs encompassing Taurus, Orion, Gemini, Canis Major, and Canis Minor. He is the important North Wind Spirit in Ojibwe, Odawa, Algonquin, and Cree cultures who ushers in the cold north wind of winter and rules over winter skies.

The January Full Moon is the “Moon after Yule” or “Old Moon.” Colonial Americans called it the “Winter Moon”, Celts called it the “Quite Moon”, and Medieval English referred to it as the “Wolf Moon.” Chinese call it the “Holiday Moon” and Anishnaabe (Odawa and Ojibwe) of northern Michigan call it “Gichi-manidoo-giizis” (Great Spirit Moon).

Apogee distance (maximum distance) is 251,909 miles (63.56 Earth Radii) from Earth on the 9th at 1:18PM EST. The Moon is nearest (perigee) in its orbit (223,473 miles or 56.39 Earth Radii) on January 21 at 3:07PM EST.

Planet..Constellation..Magnitude..Moon Passage..Moon ……………………………………………………………Phase/Age

Sun…Sagittarius………-26.8………….8:14AM EST, 1/20 ……………………………………………………..New ~ 0 days Mercury..Capricornus….+0.3……….7.0°N, 1PM EST, 1/21 …………………………………………Waxing Crescent ~ 0.66 days Venus…..Capricornus….-3.9………6.0°N, Midnight EST, 1/21 …………………………………………Waxing Crescent ~ 0.657 days
Mars……..Aquarius……..+1.1……..4.0°N, Midnight EST, 1/22 ………………………………………….Waxing Crescent ~ 1.66 days Jupiter….Leo…………….-2.4……….5.0°S, 3AM EST, 1/8 ………………………………………….Waning Gibbous ~ 17.27 days Saturn…..Scorpius……..+0.6……….1.9°N, 7AM EST, 1/16 ………………………………………….Waning Crescent ~ 25.43 days Uranus….Pisces…………+5.8………0.6°N, 7AM EST, 1/25 …………………………………………..Waxing Crescent ~ 4.95 days Neptune..Aquarius……..+7.9………4.0°N, 8PM EST, 1/22 …………………………………………..Waxing Crescent ~ 2.49 days