Astronomy news for the week starting Friday, May 10, 2013.
The Moon spends the week waxing through its crescent phase. For those with clear
northwestern horizons it will be just barely visible the evening of
Friday, May 10, in bright twilight with Venus just up
and to the right of it: a difficult sight at best. By the evening
of Saturday the 11th, the growing but still thin crescent will be
much more visible and will make a fine display as it sits a few
degrees below bright Jupiter. By the following night, the Moon will
have moved to appear up and to the left of the planet. On the
night of Tuesday the 14th, look for it passing south of Castor and Pollux in Gemini. Continuing to fatten, the crescent phase
finally ends at first quarter the night
of Friday the 17th about the time of Moonset in North America.
Look for Regulus to the northeast
of it. On Monday the 13th, our companion passes apogee, where it is farthest from the Earth on its
monthly round.
Even though Venus, as noted above, is coming into visibility, it has
not yet arrived in any obvious way. And with
Jupiter setting just after the end of twilight, the planetary
sky is diminishing. The only planet we have to admire in any
serious way is Saturn.
Which is perhaps enough for now. Well up in the southeast in early
evening about 15 degrees to the east of Spica (the two making a distant pair),
the ringed planet crosses the meridian to the south around midnight
Daylight Time. Practically on the Libra-Virgo border,
Saturn stays with us the entire night, not setting in the southwest
until dawn lights the eastern sky. Among the ancient planets, that
leaves
Mercury, which passes superior conjunction with the Sun (on the
other side of it) on Saturday the 11th as it prepares for a decent
evening showing in early June.
Leo, with its sickle-shaped
foreparts, lies high to the south in early evening, the Big Dipper well to the north of it
and nearly overhead. Between the Lion's head and the Dipper's bowl lie
the dim stars of modern Leo Minor,
the smaller Lion. Below the Sickle are the equally faint stars of
modern Sextans, the Sextant. High to the southeast in
early evening find bright orange Arcturus, which lies at the
southern end of kite-shaped Bootes,
the Herdsman. It begins a progression of constellations that
extends eastward, the first of which is semi-circular Corona Borealis, the Northern Crown.
Its counterpart, Corona Australis,
will be out of sight below summer's Sagittarius.
