SKYLIGHTS
Astronomy news for the week starting Saturday, May 13, 2000.
The next Skylights will appear at the normal time next Friday, May
19. The sky is quiet, the Moon expanding through its waxing
gibbous phase to full, that phase reached the night of Wednesday,
the 17th, around the time of midnight. As a result, the not-quite-
full Moon will rise just before sunset the night of the 17th and
the just-past-full Moon will set just after sunrise the morning of
Thursday, the 18th. This being the month before the solar passage
of the summer solstice, the full Moon (the "Planting Moon, "Flower
Moon") will be low, between the stars of Libra and Scorpius,
opposite the high solar location near the Aries-Taurus border.
The ancient planets still hide near the Sun. To the east of the
Sun, in the evening sky, Mars is slowly being overtaken by the
solar disk, while Mercury draws away, heading for its greatest
elongation on June 9. To the west of the Sun, in the morning sky,
we see the reverse, as Venus draws closer to the Sun in preparation
for its superior conjunction on June 11, while The "big guys,"
Jupiter and Saturn, both pull away, though neither will be easily
visible until June. With the Great Gathering of 2000 now breaking
up, note that the dire predictions of doom and destruction were not
fulfilled.
Mercury, Venus, Earth, Mars, and then the asteroids, a
conglomeration of small bodies that lie between Mars and Jupiter
that might have melded into a real planet had Jupiter's gravity not
so disturbed them. Instead, collisions among them now break them
into smaller bodies. The largest, Ceres, is only 1000 kilometers
across, just 30 percent the size of the Moon. Ceres, which
requires large binoculars or a small telescope to see, ceases its
backward, or retrograde, motion this week, on Sunday the 14th.
While the planets (with the distinct exception of Pluto) all lie
close to the same plane and are found near the ecliptic, the
asteroids (again because of Jupiter's gravity) scatter well away
from it. Ceres is now just barely across the northern border of
Virgo and actually within the confines of Coma Berenices some 14
degrees to the north of the ecliptic and just a few degrees due
east of Denebola in Leo. Moving southward, Ceres will enter Virgo
at the end of Skylight's week. The Moon will pass to the south of
the little body on Sunday, the 13th.
