SKYLIGHTS
Astronomy news for the week starting Friday, January 7, 2000.
Welcome to 2000 and to the first Skylights of this "round-number
year." We welcome the week and the year with a new round of lunar
phases. Since new Moon took place around noon on Thursday, January
6, the ultra-slim crescent will just barely be visible in the
southwest after sundown the night of Friday the 7th. In older
times this first appearance of the Moon was in fact called the "new
moon," and marked the beginning of the month in lunar calendars
(which it still does). As the crescent waxes, it will make a close
pass to Mars on Monday, January 10, and appear just to the left of
the planet that evening. The Moon will then reach its first
quarter next Friday, the 14th.
Mars does not move that much more slowly in orbit than we do, and
as a result it takes the Earth a long time to catch up with it and
a long time to leave it behind (which it is doing now). The red
planet will remain visible in the evening after sunset throughout
the winter and even into next spring, not actually going into
conjunction (and behind) the Sun until next July. It recently left
Capricornus, and is now sailing easterly through the stars of
central Aquarius about 10 degrees south of the famed "Water Jar."
Much more prominent, and dominating the evening sky, is bright
Jupiter, now high to the south in early evening among the stars of
southeastern Pisces. Not far to the left is Saturn in southern
Aries. The ringed planet stops its retrograde (westerly) motion
this week on Wednesday the 12th, and begins its normal easterly
motion once again. Since Jupiter is closer to the Sun than Saturn,
the giant planet moves faster and will catch up with Saturn,
passing it next May 31st in a 20-year "grand conjunction" that will
be visible in the early morning sky after the two pass behind the
Sun. Venus too celebrates the new year, as it dominates the
morning sky, brilliantly visible in the southeast. This, the
nearest of planets, will drop progressively farther toward the
eastern morning horizon at dawn, but will remain visible in
twilight into the spring.
When the Moon passes Mars on Monday the 10th, look down and to the
left for the bright star Fomalhaut, autumn's classic star, which is
disappearing into twilight. The stars of winter now take full
charge, mighty Orion crossing to the south before 11 PM, brilliant
Sirius in Canis Major down and to the left, great Taurus with its
two clusters, the Hyades (which makes the face of the celestial
Bull) and the Pleiades (Seven Sisters) up and to the right.
Overhead find Auriga the Charioteer, which carries the sky's sixth
brightest star, yellow-white Capella. Up and to the left of Orion
is the zodiac's Gemini, and directly to the left Procyon in Canis
Minor, this wonderful grouping collectively called the "winter-
six."
