Skylights featured three times on Earth Science
Picture of the Day: 1
, 2
, 3
, 4
.
Photo of the Week.. A jet contrail, seen close-up
from an aircraft, exhibits marvelous turbulent eddies and throws
its shadow onto hazy high clouds below.
Astronomy news for the week starting Friday, December 26, 2003.
Happy New Year to all, and the best for 2004.
The Moon continues through its waxing crescent phase the early part
of the week, and then reaches its first
quarter the morning of Tuesday, December 30, well before it
rises. With the Sun just past the Winter Solstice in Sagittarius, the quarter, 90 degrees to the east of the
Sun, will be somewhat past the Vernal
Equinox in Pisces and just
slightly north of the celestial equator and, about where the Sun
will be in another three months. The night of Monday, the 29th,
the Moon will pass nicely to the south of reddish Mars, which is seen due
south around 6 PM just to the east of the Circlet of Pisces. Falling only slowly behind the
Earth, Mars will be with us in the evening sky until the middle of
next summer.
The "bookends" of the ancient planets (those known since ancient
times),
Mercury and
Saturn, bookend the week as well. On Friday the 26th, just as
Skylights' week begins, Mercury passes inferior conjunction with
the Sun (where it is
aligned with, but not crossing in front of, the Sun), and at that
time makes its passage into being a morning object. Then to
celebrate the end of 2003, on Wednesday, the 31st, New Year's Eve,
Saturn, beautifully ensconced in Gemini to the east of the Summer Solstice, passes opposition to the Sun, at which
point it rises at sunset, sets at sunrise, is high to the south at
midnight, and has its maximum
retrograde (westerly) motion against the starry background. In
between, Venus passes two degrees to the south of
Neptune the night of Monday, the 29th,
the same night the Moon visits Mars. To round out the planetary
show, admire bright
Jupiter, which is now rising in southern Leo around 10:30 PM.
With the Sun just to the east of the Winter Solstice, Orion now rises around sundown, and
is nicely up in the east as twilight ends, its two first magnitude
stars, reddish Betelgeuse and
blue-white Rigel respectively at
the northeast and southwest corners of the brilliant constellation.
Just to the northwest of Rigel is the star Cursa, which marks the beginning of Eridanus, the River, which flows 30
degrees to the west of Orion before dropping sharply to the south,
meandering back to the east, and then plunging below the horizon
for those at mid-northern latitudes, where it ends in brilliant Achernar. Meanwhile, back in the
northern sky to the northwest of Orion, find the Seven Sisters star
cluster (the Pleiades)
of Taurus, six of which are readily visible with decent eyes.
