Skylights featured five times on Earth Science
Picture of the Day: 1
, 2
, 3
, 4
, 5
Photo of the Week. A beautifully colored sundog
(top), caused by refraction of sunlight through ice-crystal clouds,
shines to the east of the Sun in early February, 2006. The white
"parhelic circle" that extends farther to the east, caused by
reflection of sunlight from these same crystals, continues in the
bottom picture through a set of stunning wispy ice-clouds. A similar view lay to the west of the Sun.
Astronomy news for the two-week period starting Friday,
February 24, 2006.
Skylights will resume its weekly schedule on Friday, March 10.
Thanks for your patience.
Read A Minute
with Jim Kaler, a brief interview about the outer bodies of the
Solar System that appears on the U of I home page.
Beginning our fortnight in its waning
crescent phase, the Moon passes new on Monday, February 27.
Watch it stand far below Venus in the southeastern sky the morning
of Saturday the 25th. The evening of Tuesday the 28th, you may get
a glimpse of the waxing crescent
in western evening twilight down and to the left of rather bright
(but low) Mercury, which on Friday the 24th is just
past its greatest eastern elongation. The first night of March
finds a more-visible crescent rather well above the little planet.
As the Moon heads toward its first
quarter on Monday, March 6, it plows through Taurus, and is seen west of the Pleiades the evening of Saturday
the 4th and to the east of the cluster (nicely between it and Mars) the night of Sunday the 5th. The night
of the quarter (Monday the 6th), it is seen to the east of Mars as
it heads toward Elnath (Beta
Tauri). During the remainder of the period, the Moon waxes in its
gibbous phase
as it passes high through Gemini. The night of Thursday the 9th our lunar
companion will be along a line drawn to the east through Castor and Pollux, and just to the west of Saturn. Then on Saturday, February 25th,
the Moon passes the largest asteroid, Ceres, and
actually occults it as seen from southern South America and
Antarctica. Less than a day before new Moon, the Moon passes perigee,
where it is closest to Earth, making for especially high and low
tides at the ocean coasts.
The bright planets now parade across the sky, beginning early in
the first week with Mercury in evening dusk (it
will quickly disappear), Mars to the
west in Taurus (not setting until around 1 AM), Saturn in Cancer crossing the meridian around 9
to 10 PM (setting near dawn), Jupiter in Libra (rising shortly before
midnight and beautifully visible to the south as day breaks), and
finally brilliant Venus in southeast
morning twilight, the planet topping them all in brightness. The
night of Saturday the 4th, Jupiter begins its
retrograde (westerly) motion, while on Wednesday the 1st, Uranus is invisibly in conjunction with the Sun.
North of Orion lie the two
highest, most northerly, constellations of the Zodiac, Taurus to the northwest of the Hunter, Gemini to the northeast, the Summer Solstice (the point where we
find the Sun on the first day of Summer) right in between them,
culturally in Gemini but formally (according to modern arbitrary
boundaries) just over the line in Taurus. Taurus holds two lovely
bright clusters, the Hyades and
Pleiades, while Gemini
contains one near naked-eye vision called Messier 35, which rather closely marks the Solstice.
In a dark location with no Moon, the faint winter Milky Way
splashes down from Auriga (to
the northeast of Taurus and directly above Orion) across the
boundary between the zodiacal constellations, further glorifying
the Solstice.
