Skylights featured four times on Earth Science
Picture of the Day: 1
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4
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Photo of the Week.. The setting Sun brings the night
and the stars. Note the small upward-pointing sunpillar
caused by the reflection of sunlight from ice crystals.
The oval shape is the result of refraction in the
Earth's atmosphere, as seen better in this closeup, where you can also see that the light from
the lower edge of the Sun is asorbed more than that from the upper edge,
the result of looking through a thicker atmopshere near the horizon.
Astronomy news for the week starting Friday, March 7, 2003.
As Spring approaches and the Sun climbs
higher in the sky, we see a rather busy celestial week. The
growing Moon spans
first quarter, crescent during the early part of the week,
gibbous the latter, the quarter reached the night of Monday the
10th, just about the time of Moonset in North America. With the
Sun closing in on the Vernal
Equinox, the first quarter will be just shy of the Summer Solstice, and will be nestled
within the stars of Taurus, the
equally bright stars of Auriga
to the north of it, Saturn
just to the east as the Moon prepares to pass to the north of it.
The previous night, on Sunday the 9th, look for the crescent
between Taurus's two great clusters, the Hyades and the Pleiades. Then watch as the Moon heads towards great
Jupiter,
which it will pass the night of Friday the 14th.
While the Moon and the two giant planets dominate the evening sky,
Saturn already past the meridian to the south at sunset, Jupiter
crossing it around 9:30 PM, the morning sky is still taken up with
brilliant Venus. Though
the second planet from the Sun is getting lower in the southeastern
dawn sky, the planet rising just as twilight begins, it is still
very obvious. On Wednesday the 12th, Venus will make a very close
conjunction with Neptune, the
brightest and closest of all planets passing a mere 12 minutes of
arc to the north of the (discounting much fainter Pluto) farthest
and dimmest. Venus will then be 1.1 Astronomical Units (distance
between Earth and Sun) away, while Neptune will lie almost 30 times
farther. While admiring Venus, look for reddish Mars well to the
west of Venus. About as far south as it can get, Mars is
moving against the stars of Sagittarius, close to the Winter Solstice and just to the northeast of
Sagittarius's great Lagoon Nebula, the sight easily visible in
binoculars, as is Mars's night-to-night motion.
The brightest star in the sky and, at a distance of only 8.6 light
years one of the closest, now passes the meridian to the south
around 8 PM. Sirius is the
luminary of Canis Major, the Larger
Dog, which looks for all the world like a hound standing on his
hind legs. Down and to the left -- to the southeast -- lies one of
the great figures of the ancient sky, the sprawling constellation
Argo Navis, which memorializes the
ship of Jason and the Argonauts. The figure is so large that it
has been "broken" into three still-large constellations, Vela the Sails, Puppis the Stern, and Carina the Hull. Puppis lies adjacent to Canis Major:
look for its bright stars due south and southwest of the Dog.
Carina, which contains the second brightest star of the sky, Canopus, is below the horizon for
mid-northern latitudes, while Vela lies to the east rather between
the two.
