What's Up in the Night Sky

May 2020 - Vol. 24, No. 5

This Month's Night Sky - NOTE: The next paragraph describes the sky as it appears at 10 pm EST (11 pm EDT) near mid- month. The sky also looks this way at 11 pm EST (midnight EDT) during the beginning of the month and at 9 pm EST (10 pm EDT) by month's end.

As May brings the lengthening days, the hours of nightly observation decrease as well, it is always with a bit of sadness that we say good-bye to the Winter and Spring constellations, Gemini, Leo, and Virgo. The early evening presence of Arcturus, the second brightest star in the northern sky, reminds us that the bright star clouds of the Milky Way will soon be brightening up those dark evenings when the Moon is small enough to allow us to truly enjoy those galactic treasures. As the evening turns to morning, the bright stars of the summer triangle follow until just before sunrise, the Milky Way is at the zenith, high overhead. Long twilight hours come to the northern hemisphere.

MERCURY emerges from superior conjunction to be seen mid-month, joining Venus in Taurus near the 1.65 star, El Nath when the two planets will be less than 1 deg. apart.. VENUS in the evening sky finishing her reign in the northern hemisphere, our sister planet will be very close to the Sun by month's end. MARS in the morning sky will leave behind Capricornus as it continues its mission toward opposition later this year. By month's end the red planet will reach 0.1 mag, and rise just after 1am. JUPITER reaches its first stationary point this month and will be traveling back into Sagittarius this month. SATURN also reaches its first stationary point on the 11th this month. Keep watching this pair for the rest of the year. URANUS will emerge in the morning twilight sky. NEPTUNE in Aquarius is in the morning sky.

Review how to determine Angular Measurement.

Calendar of Events

NOTE: For those observers not in the ET zone, convert the calendar times to your zone's time by subtracting one hour for CT, two for MT and three for PT. Don't forget to adjust for Daylight Savings Time when necessary by subtracting one hour from your planisphere's time. Dawn and dusk times must also be corrected. See your local newspaper, TV news, or cable TV's Weather Channel for sunrise and sunset times or check with the U.S. Naval observatory. Unfortunately some of these events may occur during daylight hours in your area.

DATE	EVENT
04	Mercury in superior conjunction.
05	Eta aquarid meteor peak. The shower produces up to 60 meteors at its peak, but the full moon will steal its thunder.
07	Moon at perigee. This month's full moon is called the "full flower" moon. This month again full moon occurs quite near to lunar perigee and will be larger than the full moon that occurs near apogee. The full moon occurs this month at 10:45 UT on May 7.
10	Mercury at perihelion.
11	Saturn stationary.
12	Jupiter 2 deg. N. of Moon. Saturn 3 deg. N. of Moon. Check out the dance of the planets this year!
14	Jupiter stationary.
15	Mars 3 deg. N. of Moon.
18	Moon at apogee.
22	Mercury 0.9 deg. S. of Venus.
24	Venus 4 deg. N of Moon. Mercury 3 deg. N. of Moon. The two inner planets, plus El Nath lines up with the Moon! Vesta 0.6 deg. S of Moon, occultation from most of North American, Alaska, N Caribbean, NW Canada, Greenland, Most of Europe, W. Russia, and N. Middle East.

Lunar Almanac for May 2020

Phases of the Moon	Phase and Date(s)	Best viewed before local midnight
	New 22	Deep Space Objects
	1st. Qtr 30	Planets & Moon
	Full 07	Moon
	Last Qtr 14	Deep Space & Planets

Topic of the month: Virgo constellation

Virgo constellation image created in Stellarium 2020

Virgo is well known as the constellation of the Virgin. Virgo is one of the ecliptic constellations that has a long history. William Herschel noted that there are more deep sky objects in the constellation than there are bright stars. This is because a great galactic cluster is centered in Virgo. The giant galaxies M87 at the heart of the cluster is a galaxy gobbling x-ray source known as Virgo A. Other bright Virgo cluster members include M88, M89, M90, M58, and M84, that are all located in the Virgo constellation proper. It may even be that the Milky Way itself is an outlying member of this galactic supercluster.

Richard Allen in Star Names cites an observation of Saturn by the Babylonians in this constellation back in 228 BC as it passed the gamma star, Porrima. Because it lies in the Mesopotamian "path of the Moon", Virgo was observed regularly. But the constellation's history goes back long before that.

Virgo's brightest star, Spica (magnitude .95) is located very close to the modern ecliptic, in fact less then 2 degrees away from that thin line representing the plane of Earth's orbit. Its proximity to the ecliptic means that it can be occulted by the Moon, and as in 2013 when Spica was occulted 12 times, every time the Moon came near Virgo! The moon passes through Virgo every lunar month.

Spica was identified as a ripe wheat stalk in the hand of the Virgin. Theoretically, she holds a palm branch in her right hand and a stalk of wheat in the left. She celebrates the growing season and is associated with fertility. Sometimes Spica is identified as an ear of corn, that identification I hesitate to make because corn - - that is maize, is a new world product. Corn in the old world was more of a generic term for a food crop.

The star, β Virginis, commonly known as Zavijava is the constellation's 5th brightest star at 3.55 magnitude. It is even closer to the ecliptic than Spica, according to Wikipedia, it will be occulted by the planet Venus in 2069. The gamma star of the constellation is the well-known star Porrima. It is a double star, with two components at 3.65 and 3.56 magnitude. They orbit each other in 169 years, with the line of sight from Earth causes them to change their separation. They were last closest in 2005 and couldn't be split, but in 2020 they are farther apart and can be resolved in a small telescope. The distance between the two stars varies from 5 AU, (about the distance of Jupiter to the sun) to 81 AU at their farthest.

In my studies, I have encountered an abundance of names and designations for the constellation Virgo. It has been equated with Isis, Ishtar, Persphone, Demeter, Diana, Minerva, Fortuna, Bel's wife, barking dogs, a ship, a maiden in a ship and many more. It is known that sometimes the stars on the eastern side of the constellation were placed in the constellation of Libra, helping to form the image of the scale. In ancient Mesopotamia, Virgo was known as "The Furrow" or "Absinnu" in Akkadian, a constellation that celebrated their agrarian culture. It was a land of farming and irrigation. The two great rivers, Euphrates and the Tigris did not offer up their spring floodwaters in synch with the growing season when the crops needed it, so they learned to regulate the waterways. Naturally, Spica represented barley, their most important crop. Barley was their preferred crop because of its tolerance to the briny environment they grew their crops in.

Marduk's tiara, an alternate view of Virgo

Because Marduk was the primary god of the Babylonians, following a commentary on Marduk's Address to the Demons written in the late Babylonian period by a scribe named Shema'ya and translated by John Z. Wee, I have presented here a whimsical dot-to-dot portrait of Marduk's tiara. I have reconstructed this image by rearranging the constellation lines from Stellarium.

I am always sad when the long hours of daylight and twilight in late Spring quickly wash away the winter constellations as the Sun returns to the north. Virgo will continue to rise in the northern hemisphere visible in the early evening through July.

--See You Under the Stars!
Astra for Astra's Almanac