Astronomy news for the week starting Friday, May 22, 2009.
We begin the week with a very slim waning
crescent Moon as it goes toward new on Sunday, May 24. The
last view of it was as Skylights' week opens, and it will be quite
invisible the morning of Saturday the 23rd. But after the Moon passes the Sun, it quickly becomes
visible as a thin waxing crescent in
western evening twilight, our first look at it being the night of
Monday the 25th, when it will lie just up and to the left of Elnath, Beta Tauri. As the crescent
grows, it passes through southern Gemini the evening of Tuesday the 26th, while the
following evening it will be seen a bit down and to the left of
orange-colored Pollux, Gemini's
brightest star. The Moon then heads toward its first quarter, which is not reached until
Saturday, May 30, in Leo to the
southwest of Saturn. The night
of Monday the 25, the Moon passes perigee, where
it is closest to the Earth.
With both Jupiter and Venus, the morning sky still
holds most of the planetary glory, but with Jupiter rising ever
earlier, not for long. The giant planet now makes its first
appearance in the southeast around 1:30 AM Daylight Time in far
northeastern Capricornus, not far
from the border with Aquarius. As
bright as Jupiter appears, it's very much topped by Venus. Rising
two hours later (around 3:30 AM, a hair before the commencement of
dawn), Venus is seven times brighter.
If you ever wanted to see Neptune, and have a telescope, now is
your chance. The morning of Monday the 25th, Jupiter will pass a
mere 0.4 degrees, about the angular width of the full Moon, south of the more distant planet.
Look just north of Jupiter for a day or two before and after the
formal conjunction for a star-like object that will be much fainter
than Jupiter's famed moons. Four days later, on Friday the 29th,
Neptune begins its westerly
retrograde motion. If you miss the conjunction, Jupiter will
do it again in July after it starts its own retrograde movement.
The evening of course has its own charm, compliments of Saturn.
Well into the southwest in Leo as
the sky darkens, the ringed planet now sets around 2:30 AM, in
between the risings of Jupiter and Saturn, briefly allowing one to
see the two giant planets on opposite sides of the sky.
Around 9 PM, look to the south to see the small but prominent
distorted box of stars that makes Corvus, the Crow. As the two front bowl stars of the
Big Dipper point to Polaris, the top two of Corvus point
leftward to Spica in Virgo, while the bottom two point in
the same direction to Gamma
Hydrae, allowing you to see the tail of Hydra, the Water Serpent. Quite the signpost, Corvus's
two right-hand stars then point downward to fourth magnitude Beta Hydrae, the figure's
southernmost star. Stretching westward to its head, Hydra is the
longest constellation in the sky.