Star Calendar Planets:
Moon is Full three, or sometimes four, times in a season but the names that various cultures have assigned to characterize the circumstances around various full moons of the year generally number 12 – leaving the occasional unnamed one. Similarly the Hebrew luni-solar calendar has 12 months – but needs to insert an inter-calary month about every three years to maintain its relationship to the solar year. In each case the adjustment occurs 7 times in 19 years – the extra full moon is called Blue and the extra Hebrew month is called second Adar. This month’s full Moon coincides with the opposition of Mars – and the latter will shine in the very spot towards which falls the shadow of the Earth – so on the night of the 21-22nd one can easily see just how far the moon is from being eclipsed.
Mercury promises to be visible in broad daylight on the 9th. Inferior conjunction will cut right across the face of the Sun, beginning somewhat after sunrise, midway around 11 and leaving in mid-afternoon. One can observe this with a camera obscura arrangement that projects and enlarges the disk of the sun onto a screen. I might cover a south or SE-facing window and allow a pinhole of light through a piece of aluminum foil to cast onto a sheet of white cardboard. Such a transit of Mercury last occurred ten years ago – but these are far less rare than transits of Venus – which I will never see again.
Venus is lost in morning limelight as she heads backstage for some future showing in evening attire.
Sun is midway from equinox to solstice on the 1st. Astronomically this marks the beginning of Summer, the solstice being regarded as mid-summer. The days are now getting longer much more slowly – by about one minute a day as the month opens and only 30 seconds a day as the month ends.
Mars makes a large retrograde stroke and rises dramatically earlier over the course of this and next month. He breaks the horizon at about 9 PM on the 1st and already at 6:18 by the 31st. This opposition is the nearest for Mars since the superlative one of ten years ago. But, due to Mar’s high degree of ellipticity, he will continue to draw nearer for another week after opposition, then being twice as near to us as is the Sun (.5AU).
Jupiter finally diminishes perceptibly from its late brilliance but still dominates the evening sky in the south. Mars will match magnitude during its opposition- but rises later and culminates much lower – achieving only the altitude of the Sun at mid-winter.
Saturn is also in a retrograde loop, one much smaller than Mars’, and rises just under an hour later. Saturn is then seen to be about as bright as Arcturus – but shining with a steady light compared to the latter’s yellow-green scintillation. Saturn will reach opposition on June 3rd.
Star Calendar Days:
1 Sunrise/sunset in Spring Valley at 5:53/19:54 (14h1m daylight)
First day of cross-quarter-wise summer, Beltane
6 New Moon 15 hours after perigee, again large spring tides
8 Moon to right of Betelgeuse and above Aldebaran, WNW around 9:PM
9 Mercury crosses face of Sun (transit) begin 7:12-max 11:-ending 2:40
Jupiter stationary to direct motion, ends it’s loop for this year
13 Moon next to Regulus, SW as dark falls
14 Moon next to Jupiter, SSW as dark falls
18 Moon beside Spica, SE as dark falls
21 Full Blue Moon at 17:14 (This season has 4 Full Moons, the 3rd is “Blue”
Mars rises (in the exact direction of Earth’s shadow) beside the Moon, ESE 8:30PM
Mercury stationary to direct (leftwards motion against stars)
22 Mars in opposition 7:AM, 14 hours after Full Moon
Moon rises to left of Saturn, SE at 10:PM
30 Mars is nearest Earth, half as distant as is the Sun
31 Sunrise/sunset in Spring Valley at 5:26/20:22 (14h56m daylight)