Skylights featured five times on Earth Science
Picture of the Day: 1
, 2
, 3
, 4
, 5
Photo of the Week.. Concluding the four-part
thunderstorm-from-the-air series, we depart as the setting Sun sets
storm clouds afire. See the rest of the set: a roiling thunderstorm; a close-up of an anvilled thunderstorm; inside a thunderstorm cell.
Astronomy news for the week starting Friday, August 26, 2005.
We begin the week on Friday, August 26, with the Moon in its
last quarter, the phase reached in mid-morning in North America
with the Moon in the daytime western sky moving toward its setting.
The remainder of the week sees the Moon in its waning crescent phase as it graces
the pre-dawn sky. Not only will the crescent be climbing to the
top of the ecliptic path, the
tilt of the orbit takes it a bit "over the top" within Gemini and about as far north as
possible. The Moon passes five degrees north of Saturn about noon
on Wednesday the 31st, and will therefore be to the northwest of
the ringed planet (which now rises around 4 AM Daylight Time, about
an hour before twilight begins) the morning of Wednesday the 31st,
and to the northeast of it the following morning (Thursday,
September 1). That same morning, the Moon will be just past
apogee, where it is farthest from the Earth.
The evening of Wednesday August 31, Uranus, the next
planet after Saturn (about twice as far from the Sun) and moving
retrograde through Aquarius,
passes opposition to the Sun. Though at sixth magnitude, the planet is (from a
thoroughly dark location) visible to the naked eye, appearing as
one of the faintest of stars.
The evening, however, belongs not to the outer planets but to the
brightest of the ancient planets, Venus and
Jupiter,
as the two approach each other for a very attractive conjunction in
evening western twilight. On the morning of Friday, September 2,
Venus will pass only 1.4 degrees to the south of Jupiter, out of
sight for North America. The nights of Wednesday the 31st and
Thursday the 1st, Jupiter will therefore lie just above (to the
east) of Venus in the twilight sky, the two then gradually
separating and switching places. At the same time, both planets
reach a "crossing point" as such, both setting as formal twilight
ends. Both are to the west of Spica in Virgo. Jupiter will thereafter sink into dusk, while
Venus climbs yet higher as it moves toward best visibility in late
November and early December.
Scorpius is now escaping toward the
southwest. Above it lies a relatively fainter but magnificent duo
of constellations. Ophiuchus
(the Serpent Bearer) appears as a giant pentagon actually astride
(though not formally a part of) the Zodiac. He appears wrapped in Serpens, the Serpent, the only
constellation to come in two parts, Serpens Caput (the "head," to
the west of Ophiuchus) and Serpens Cauda (the tail, to the east).
Directly north of Ophiuchus find another famed figure, Hercules, the great Hero of ancient
times.
