Photo of the Week. Misty fields await a clear
sunrise.
Astronomy news for the week starting Friday, February 22, 2008.
Having just passed full last Wednesday,
February 20, the Moon
spends nearly the entire week in its waning
gibbous phase as it heads toward third
quarter the evening of Thursday the 28th (which, 2008 being a
leap year, is not yet the last day of the month). The last day of
the week, the morning of Friday the 29th, we'll see just a hint of
the waning crescent. Almost exactly a
day before the quarter, the Moon passes apogee, where it is
farthest from Earth, at a distance about 5.5 percent greater than
average. With the Sun approaching the Vernal Equinox in Pisces (which marks the beginning of spring in the
northern hemisphere), this third quarter will be very far to the
south. The morning of Friday the 29th finds it just to the
southeast of Antares in Scorpius.
A pair of planetary events highlight the astronomical week. In the
morning hours, we see Venus
and Mercury tracking
each other, as they will over about the next month. On the morning
of Tuesday the 26th, the two will have just passed conjunction,
Mercury just over a degree to the north of its much brighter
(by about 40 times) companion. The event will be difficult to see,
as the planets do not even rise until just after dawn begins to
light the sky, and will require a good southeastern horizon and
clear air. A couple days before, on Sunday the 24th, Saturn hits a
milestone when it passes opposition with the Sun, and thus rises at
sunset, sets at sunrise, and crosses the meridian to the south at
midnight. Look for it in Leo, just
to the east of Regulus, the
planet some three times brighter than the star.
The evening and morning, however, are really dominated by Mars and
Jupiter. Mars,
reddishly bright in far eastern Taurus three degrees north of the Summer Solstice, transits high to the south just as the
sky fully darkens at the end of twilight. It then sets around 3
AM, and is replaced about an hour later by
Jupiter rising in the southeast, the planet lying in a fine
setting to the north of the Little Milk
Dipper of Sagittarius.
As the sky darkens and you admire Mars, be sure to look farther
overhead for Auriga, the
pentagon-shaped Charioteer, which is notable for bright yellow-
white Capella, the most northerly
of first magnitude stars. Its name meaning "the she-goat," Capella
is just northeast of a small, lovely triangle that together make
her "Kids." To the south, Orion stalks before his two dogs, Canis Major (with Sirius, the sky's brightest star) and
Canis Minor, which holds Procyon.
