Skylights featured five times on Earth Science
Picture of the Day: 1
, 2
, 3
, 4
, 5
Photo of the Week.. Darkened sunset.
Astronomy news for the week starting Friday, September 2, 2005.
We pass through new Moon this week, the skies fully dark again, at least as long as
you live out of town. New phase, with the Moon more or less
between us and the Sun, takes place on Saturday, September 3. By
the night of Sunday the 4th, the Moon will be barely visible as a
slim crescent in bright western evening
twilight.
The real action takes place a couple days later. Having just
passed their September 2 conjunction, Venus
and
Jupiter, both brilliantly obvious in the west during evening
twilight, are pulling apart, Jupiter dropping down some, Venus
shifting a bit higher (if observed at the same twilight time) and
to the south. The last time they were this close was in the
morning hours of early November, 2004.
The night of Tuesday the 6th will witness a great gathering of the
waxing crescent, the two planets,
and the star Spica in Virgo. Look for the Moon shining
below the planetary pair, while the star will be directly below
Venus. The Moon will actually occult both Venus and Spica, but not
for anyone in the Americas. As the Moon pulls away to the east,
the following night (Wednesday the 7th) will find it, Venus, and
Jupiter all in a fine row. The sight will be well worth an effort
to find a decent horizon to allow full appreciation.
During the remainder of the week, the crescent waxes toward the
deep south and first quarter, that phase however not reached until
Sunday the 11th.
The bookends of the Solar System are more subtle and pretty much
out of sight. Mercury
passes north of Leo's Regulus in bright twilight the
morning of Sunday the 4th, while Pluto
(if we still wish to call it a planet, since it is now beaten in
size by
another Kuiper Belt object, your scribe's opinion that once a
planet, always a planet) ceases retrograde motion on Friday the 2nd.
In between, Saturn
is now rising about 3:30 AM Daylight Time, well in advance of
twilight, the planet now in Cancer
near the Beehive star cluster.
Much brighter is Mars,
which is now up in the east by 10:30 PM DST.
So many constellations come in pairs of some sort. Witness Ursa Major (the Greater Bear), Ursa Minor (the Smaller Bear); Canis Major (the Larger Dog), Canis Minor (the Smaller Dog); Corona Borealis (the Northern Crown),
Corona Australis (the Southern
Crown); and several more if you count modern and defunct (no-
longer-recognized) constellations: Hydra (the Water Serpent), Hydrus (the Water Snake); Musca Borealis (the expired Northern
Fly), Musca Australis (the Southern
Fly, now known just as Musca). In late summer, however, enjoy some
single figures, especially Lyra
(the Lyre), which with Vega strums
nearly overhead in early-evening North America.
