Photo of the Week.. In contrast to the
22-degree lunar halo, here is one around the Sun. Caused by refraction through ice-crystal clouds,
it is colored red on the inside, blue on the outside.
Astronomy news for the week starting Friday, November 30, 2012.
The Moon spends most of the week sailing through its waning gibbous phase until it passes third quarter on the morning of Thursday,
December 6, gliding against the stars to the south of Leo. The morning of Friday the 7th
then sees it just barely into the waning
crescent phase. Sadly there are no planetary passages to
watch.
The planets, though, do it on their own. Going from the evening's
western sky, we can first pretty much ignore Mars,
which, though still tracking the end of twilight (setting half an
hour after the sky is dark), is ever so slowly being lost
altogether. Far more interesting is
Jupiter, which on Sunday the 2nd goes through opposition to the
Sun. Up all night, the giant and wonderfully bright planet
rises at sundown, crosses the meridian
high to the south at midnight, and sets at sunrise. In
celebration,
retrograding (moving westerly) against the stars of Taurus, Jupiter will also pass five
degrees north of Aldebaran on
Friday the 7th, the two providing a nice color contrast, the planet
nearly 30 times brighter than the star.
Hard to believe, but the morning sky show is even better. Venus, three
times brighter than Jupiter, rises shortly before 5 AM, Saturn beating
it by nearly an hour. Mercury, which
goes through greatest western elongation against the Sun on Tuesday
the 4th, is last up, hitting the skies at the start of morning
twilight. By the time dawn has advanced a bit, the star Spica, Saturn, Venus, and Mercury will
form a nice line pointing down and to the left, providing a good
way of locating elusive Mercury, which never ventures very far
in angle from the Sun.
Jupiter, which temporarily locates Taurus, is about as far north of
the celestial equator as it is going
to be for at least awhile. To the west, find the flat triangle
that makes the classical figure of Aries, the Zodiacal
Ram, while farther along to the southwest lies sprawling Pisces, the Fishes with its western
"Circlet." To the east of
Jupiter is bright Gemini, the
Twins (made notable by the stars Castor and Pollux), which will embrace Jupiter
later next year, the planet taking about a year to move through
each of the constellations of the
Zodiac.
