March Skies News – 2019
03/4/2019
March Skies – by Dick Cookman
Highlights: Comet Journal, Martian Landers, Meteor Showers, Planet Plotting, Spring Equinox, March Moon
Focus Constellations: Perseus, Auriga, Taurus, Orion, Canis Major, Canis Minor, Gemini. Cancer, Leo, Leo Minor, Coma Berenices, Bootes, Ursa Major, Ursa Minor, Draco, Cepheus, Cassiopeia, Camelopardalis, Lynx
Comet Journal
C/2018 Y1 (Iwamoto) is an evening comet at 8th magnitude in Auriga and Perseus setting after midnight in March. It passed through perihelion south of western Virgo on Feb. 6th and was closest to Earth (28 million miles) in Leo on Feb. 11th & 12. It will move westward, paralleling the ecliptic during March, and will reach Auriga by month’s end. It is now exiting the inner solar system and returning to its aphelion between the Oort Cloud (10000+ AU’s) and Kuiper Belt (30 – 50 AU’s,) the normal homes for longer period comets.
Comet 46P/Wirtanen (2018) has decreased to 10th magnitude as it leaves western Ursa Major and enters Leo Minor in March. It is a short period comet returning to the Asteroid Belt.
Mars Landers
The Opportunity rover is now officially considered inoperable after the global dust storm on Mars during opposition last summer, no signal has been heard since Sol 5111 (June 10, 2018.) NASA’s Jet Propulsion Lab attempts to send newly revised commands to Opportunity failed to rouse a response and further attempts have now been abandoned.
After arriving in Elysium Planitia on Mars on Nov. 26th, the InSight lander unfurled its solar panels and radio antennas. Preliminary deployment of the seismometer on the Martian surface was achieved on December 19. space.com states: “InSight’s Heat Flow and Physical Properties Package (HP3) instrument burrowed underground for the first time on Feb. 28. After 400 hammer blows over the course of four hours, the instrument apparently got between 7 inches and 19.7 inches (18 to 50 centimeters) beneath the red dirt — but obstacles slowed its progress.
The Curiosity Rover is investigating 16,404 foot Mt. Sharp at Gale Crater’s center in its search for evidence of pre-existing life on Mars. Central mountains often appear in impact craters and are thought to result from crustal rebound in the area most highly compressed by the impact. Alternatives to this hypothesis include erosional remnants in craters which were filled with layers of sediments and/or lava flows and then underwent erosion which worked its way inward from the margin of the crater to the uneroded remnant. Based on studies by Curiosity which reveal that variations in gravitational fields along the rovers traverse, the sedimentary layers in the crater and on Mt. Sharp’s lower slopes are unusually porous, much more porous than would be expected in layers compressed by impact or overlain by thousands of feet of sediment/lava layers. This porosity may indicate that the above alternatives for the formation of Mt. Sharp may be inadequate explanations. Instead, the mountain may have formed as sediments carried by inflowing wind and water built a free standing mound in the crater’s center.
Curiosity’s next destination is to study the clay-bearing unit adjacent to Vera Rubin Ridge, the target of investigation of the rovers activities for the last 17 months. Clay minerals in this unit may hold more clues about the ancient lakes that helped form the lower levels on Mount Sharp.
Meteor Showers
Mar. 24: Virginids. Peak 5 UT Active Jan 25-Apr 15. Radiant 13h00m -04°. ZHR ~5. 30 km/sec. 4 days after Full Moon. Progenitor: Unidentified – possibly an asteroid
Mar. 13 Wed.: Gamma Normids Peak 7 UT? Active Feb 25-Mar 22. Radiant 16h36m -51°. ZHR ~8?. 56 km/sec. 1 day before 1st quarter Moon. Progenitor: Unidentified – possibly a comet
Planet Plotting
Mercury (-0.2 to +1.0) is in Aquarius and Pisces in March and is visible in the southwestern sky in the first week of March after passing through Maximum Eastern Elongation on February 26. It is within less than 8° of the thin waxing crescent Moon at 2:00 PM EST on the 9th as it drops into the glow of sunset before reaching inferior conjunction with the Sun at 10:00PM EDT on the 14th. It will reappear low in the morning sky before dawn at months end.
Mars (1.2 to 1.34) in Aries and Taurus and Uranus (+5.9) in southwestern Aries are in the early evening western sky in March, setting well before midnight. A waxing crescent Moon is 5.0°S of Uranus at 11:00PM EST on the 9th and 6.0°S of Mars at 8:00AM EDT on the 11th. Uranus will drop lower into the setting Sun’s glare during the month while Mars appears higher in the western sky as it moves eastward and does not set until after 11:00PM EDT at the end of March. As it moves into Taurus, it appears to pass 3°S of the Pleiades star cluster (known to the Japanese as Suburu) on the 29th and 30th.
The waning crescent Moon passes Saturn (+0.6) in Sagittarius twice in March. On the 1st it is 0.3°N of the planet at 1:00PM EST and is 0.25°E at 5:00AM EDT on the 29th when both are visible in the eastern predawn sky. Jupiter (-1.9 to -2.1) in nearby Ophiuchus is also a morning planet, rising earlier than its ringed companion. Venus (-4.0 to -3.9) in Capricornus and Aquarius rises after the giant planets yet dominates them in brightness. Before dawn on the 13th, the 3 planets are spaced equally along the ecliptic from Ophiuchus through Capricornus. The waning crescent Moon is 1.2°S of Venus at 4:00PM EST on the 2nd, and the waning gibbous Moon is 1.9°N of Jupiter at 10PM EDT on the 26th.
Neptune is hidden behind the Sun throughout March, reaching conjunction with the Sun at 8:00PM EST on the 6th.
Planet..Constellation(s)..Magnitude..Planet Passages…………………………………………….Time………….Date
Sun..Aquarius, Pisces..-26.8..New Moon..11:04AM EST..3/6
Mercury..Aquarius, Pisces…-0.2 to +5.0 to +1.0…….Inferior ………Çonjunction…………..10:00PM EDT..3/14
Venus…Capricornus, Aquarius..-4.0 to -3.9
Mars…..Aries, Taurus…………….+1.2 to +1.4
Jupiter…Ophiuchus……………….-1.9 to -2.1
Saturn…Sagittarius……………….+0.6
Uranus…Aries………………………+5.9
Neptune..Aquarius………………..+8.0…………Solar Conjunction …………………………………8:00PM EST..3/6
………………………………………………………………………………………………………………………….1:00AM EST..2/19
Spring Equinox
The Vernal Equinox on 3/20 at 3:48PM EDT can be used to determine the astronomical date of Easter. The Christian definition states that Easter, the most important holiday of the Christian calendar, occurs on the first Sunday following the first “paschal” full moon after the Vernal Equinox. In 2019, Easter should occur on March 24 since the full moon on the 20th is ~5 hours after the equinox, making Sunday the 24th the date of Easter, the earliest date for Easter since 1913.
However, the 2019 calendar lists April 21 as Easter, the latest Easter of the 20th & 21st centuries. In order to simplify previous calculations, the Christian Church specified that the paschal full moon need not coincide with the astronomical full moon. The former was defined as always occurring on the 14th day of the lunar month. In addition, the Church specified that the Vernal Equinox was to be redefined as March 21. The astronomical definition for the equinox is that the date varies due to when Earth’s axis is oriented at precisely 90° to a line between Earth and Sun so that the entire Earth experiences 12 hours of daylight and 12 hours of dark (assuming a horizon free of obstructions). Thus, Christian definitions for the full moon and the equinox ignore real astronomical arrangements because the ancient Christians did not have the ability to precisely measure the astronomical motions of the Earth, Sun, and Moon.
If you wish, you are astronomically justified in coloring and hiding a few eggs and eating chocolate bunnies on March 24.
March Moon
The New Moon of March is on the 6th at 11:04AM EST. It is the beginning of Lunation 1190 which ends 29.71 days later with the New Moon of April on the 5th at 4:50AM EDT.
The Full Moon on the 20th at 9:43PM EDT is the first spring full moon of 2019. The March Moon is known as the “Sap, Crow, or Lenten Moon”. Since the Full Moon is ~30 hours after perigee, when the Earth and Moon are closest, the Full Moon appears larger than normal producing a “supermoon” for the third month in a row! Colonial Americans called the March Moon the “Fish Moon” and Celts called it the “Moon of Winds”. It was the “Chaste Moon” in Medieval England to symbolize innocence and fruitfulness associated with spring. Chinese refer to it as the “Sleepy Moon” and the Anishinaabe (Odawa and Ojibwe) people recognize it as “Onaabani-giizis” (Snowcrust Moon).
Lunar Apogee (maximum orbital distance) occurs on the 4th at 6:26AM EST when the Moon is at 252,519 miles (63.72 Earth radii). Another Apogee occurs on the 31st at 8:14PM EDT when the Moon is 252,014 miles from Earth (63.59 Earth radii). Perigee occurs on the 19th at 3:48PM EDT when the Moon is at a distance of 223,307 miles (56.34 Earth radii).
Planet..Constellation..Magnitude..Moon Passages……………………………………………………Moon Phase..Moon Age
Sun……Aquarius……..-26.8…..11:04AM EST, 3/6..New..0 days
Mercury..Pisces………+2.8…….7.9°SSE, 2:00PM EST, 3/9 …………………………………..Waxing Crescent..3.12 days
Venus….Capricornus..-4.0…….1.2°S, 4:00PM EST, 3/2 ………………………………………Waning Crescent..26.00 days
Mars……Aries…………+1.3……..6.0°S, 8:00AM EDT, 3/11 …………………………………….Waxing Crescent..4.87 days
Jupiter…Ophiuchus….-2.1……..1.9°N, 10:00PM EDT, 3/26 ………………………………….Waning Gibbous..20.46 days
Saturn…Sagittarius….+0.6……..0.3°N, 1:00PM EST, 3/1 …………………………………….Waning Crescent..24.87 days
………………………………………….0.25°E, 5:00AM EDT, 3/29 ………………………………….Waning Crescent..22.75 days
Uranus…Aries…………+5.9………5.0°S, 11:00PM EST, 3/9 …………………………………..Waxing Crescent..3.50 days
Neptune..Aquarius…..+8.0……….3.0°SSE, Noon EST, 3/6 …………………………………..Waxing Crescent..1.04 days
