Photo of the Week. The near-full Moon watches over
the rising shadow of the Earth at sunset.
Astronomy news for the week starting Friday, May 9, 2008.
The
Moon waxes from crescent through first quarter this week, the quarter passed
on Sunday, May 11, with the Moon going down the western sky, after
which it fattens through the waxing gibbous
as it heads toward full phase next week. The evening of Friday
the 9th finds the Moon just to the west of Mars, while by the
following evening (Saturday the 10th), the Moon will have moved to
the other side of the red planet. Now in Cancer, Mars stands well to the east of classical Gemini. A fine sight in the
evening's west to the left of Castor
and Pollux,
Mars does not set until just after local midnight
(1 AM Daylight Time).
Then it's Saturn's turn. On the evening of Sunday
the 11th, the Moon will lie rather well to the west of Saturn and
Leo's Regulus (Saturn the brighter of the
pair), then the following night (Monday the 12th) it will be just
to the east of them, having passed just three degrees to the south
of the planet shortly before Sunset. Saturn now transits the meridian just at the Sun sets, then stays up
chasing Regulus until 2:30 AM Daylight.
The biggest and (excepting Pluto) smallest planets make a
splash, as (anticipated last week) on Friday the 9th,
Jupiter stops moving westerly against the stars of northeastern
Sagittarius and begins to move
retrograde as the Earth prepares to swing between it and the
Sun. Look for the giant planet rising in the southeast around
12:30 AM Daylight.
Mercury then passes
greatest eastern elongation (22 degrees to the east of the Sun) on
Tuesday the 13th. Given that the evening spring ecliptic stands
well up against the horizon, this closest planet to the Sun is
giving its very best evening showing of the year. Look for a
bright "star" in low western evening twilight, the planet not setting
until formal twilight is over.
Look high in late evening to find Ursa
Major's Big Dipper. Then,
as told to generations of those learning the constellations, follow the curve of
the handle to the south through Bootes' Arcturus
(the brightest star of the northern hemisphere) and then to Virgo's Spica. Down and to the left of Spica
is one of the dimmer constellations of the Zodiac, the distorted box that makes
Libra, the Scales, which 3000
years ago held the Autumnal
Equinox, hence its name, signifying the balance of days. The
constellation is perhaps best known by its two beloved stars that
represent the outstretched claws of Scorpius, Zubenelgenubi (the Southern Claw)
and Zubeneschamali (the
Northern).
