Photos of the Week.Low and
high tides (Jekyll Island Georgia),
showing the gravitational power of the Moon and Sun.
Astronomy news for the week starting Friday, April 5, 2013.
We pass through new Moon this week on the morning of Wednesday,
April 10. Prior to the "dark of the Moon," when our companion
closely faces the Sun and reflects
almost no sunlight to us, we see it in the morning hours as a waning crescent. Your last look at it will
probably be on the morning of Monday the 8th; by the following
morning the crescent will be ultrathin
and close to the horizon. After new, the Moon switches to waxing crescent in the western evening sky.
Look for it first during twilight the evening of Thursday the 11th,
after which it will climb the western sky past the Pleiades and Hyades clusters, Aldebaran, and Jupiter. But that
is a topic for next week. In both the morning and evening
crescents, you can admire earthlight (light reflected from the
bright daytime side of Earth) onto the nighttime side of the Moon,
which allows the whole disk to become
visible.
On the morning of Monday the 8th, the Moon skates 7 degrees north
of Mercury,
which is making a poor appearance in dawn skies, while two days
before it slides equally well north of Neptune, the two planets
more or less lined up, though Neptune is more
than 30 times (going on three billion miles) farther away.
With Mars and
Venus far too
low in the west after sundown to see, the only planets readily
available are our old friends Jupiter and Saturn. The
giant of the Solar System leads the way. Just over five degrees
almost due north of Aldebaran in Taurus, Jupiter is well into western skies in early
evening, finally setting around midnight Daylight Time.
Encroaching for a few hours on Jupiter's time of visibility, Saturn
then rises in the southeast around 9 PM Daylight in Libra rather well to the east of Virgo's Spica. With us the rest of the night,
the ringed planet then transits the meridian to the south about 2:30 AM. For
a change of pace, try to see Comet Pan-STARRS
very low in northwestern evening twilight. You'd best use
binoculars.
To the east of Procyon (which
shines brighter than reddish Betelgeuse to west of it, a
consequence of Procyon's proximity) lies the head of Hydra, the
Water Serpent. The longest constellation in the sky, the giant
snake runs far south of Leo, then
closely south of faint Crater (the
Cup) and obvious boxlike Corvus
(the Crow, whose top stars point easterly to Spica), then finally
winding up south of eastern Virgo, roughly several degrees south of the current
position of Saturn: quite a stretch.
