Star Calendar
April 2015
Star Calendar Planets:
Moon and Sun cycles interacting generate the modern (Mainmonedesian) “lunisolar” Hebrew calendar. The calendar day begins just after evening civil twilight with the light and dark portions each then being divided into 12 hours. The month begins with the evening following New Moon. On seven occasions within a 19-year cycle of years an extra (intercalary) month is inserted to keep the normal months aligned with the seasonal solar year so that the year begins with the New Moon placed such that the following Full Moon (Nisan 15) occurs on or after the spring equinox. That Full Moon begins the seven days of Pesach or Passover. In the Gospels of Matthew, Mark and Luke, the Last Supper takes place at the beginning of Friday (! – n.b. EVENING begins the day!) Nisan 15. The crucifixion occurs during the following daylight hours (Good Friday) and Easter is the next Sunday. Various attempts to be faithful to, or emancipated from, various historical and/or astronomical aspects, or to regularize dates, have caused enormous complexities in defining the date of Easter. The fact is that Easter is a unique event – its historical/astronomical circumstances simply do not recur. So we might simply commemorate its spirit. Eastern churches use a 19-cycle formula for Paschal Moons, from Nicaea AD 325, to fix the date of Easter on the Julian Calendar. Western churches have gradually moved to the Gregorian Calendar, since AD 1583, and have an 84-cycle formula. Even when the two Easters occur on the same day – they’re still on different dates! Note that even a purely astronomical definition of Passover or Easter is troublesome since, due to time zones, world-wide astronomical events occur on two dates simultaneously!
Mercury crosses behind the Sun during the night of the 9th-10th.
Venus passes the Pleiades (aka “seven sisters”, one of which is called “Subaru” in Japan) during the second week of this month. Look west each evening between about 8:30 and 9PM.
Sun gave us a surprise wallop mid-March; resulting in some radio disturbances and intense Aurora.
Mars begins a three-month hiatus in the middle of this month and will reappear by mid-August.
Jupiter resumes direct (leftwards) motion amongst the stars on the 8th and begins to head for Regulus again. He will cross into the realm of Leo in early June and reach Regulus in August.
Saturn is now retrograde and will find its opposition in May. Saturn brightens much less dramatically than Jupiter.
Musing on Pi-Day: The words “cycle”, “circle”, “ring”, “year”, “annual” etc. are all related. If a “year” is seen to be a “circle” with a circumference of 365.2425 days then it follows that the year-circle should have a time-diameter of 116.2603 days and that we might celebrate “diameter day” on April 26th (at 6:14:50 AM). We might further determine that the year-circle has an area of 10,615.8 square days, and, to make a total conflation of space/time, the year-sphere has a volume of 822,797.4 cubic days. Oooh, what a headache.
Star Calendar Days:
1 Sunrise/sunset in Spring Valley at 6:40/19:21 EDT (12h41m daylight)
3 Passover begins in evening
4 Full Paschal Moon 8:06AM
Lunar eclipse for the anti-Greenwich meridian (Pacific hemisphere)
5 Easter Sunday for Western churches
8 Moon approaching Saturn, early morning SSW
Jupiter stationary (to stars), resumes “direct motion”
9-10 Mercury crosses behind Sun, “superior conjunction”
11 Venus nearest Pleiades, 8:30-9:30PM in west
12 (Julian March 23) Pascha Sunday for Eastern churches
21 Moon and Venus dazzle the eye of Taurus (Aldebaran) 9:PM-ish in west
23 Lyrid meteors peak, raying from NE in late evening to early morning
25-26 Moon near Jupiter in evening, WSW
26 A diameter-of-days have passed along year’s circumference
30 Sunrise/sunset in Spring Valley at 5:55/19:52 EDT (13h57m daylight)
