Astronomy news for the week starting Friday, July 11, 2008.
The Moon brightens this week from waxing
gibbous through full, that phase
reached as our week comes to an end the morning of Friday, July 18.
Look the evening of Thursday the 17th to see the not-quite-there-
yet-full-Moon rising just barely before sunset. The waxing gibbous
passes apogee, where it is farthest from the Earth, the night of
Sunday the 13th. With the Sun now descending the
ecliptic within the confines
of Gemini, this full Moon (the
"Thunder Moon," the "Hay Moon") will be just a bit higher in the
sky at midnight than it was last month.
As the Moon waxes, it passes barely south of Antares in Scorpius the morning of Monday the 14th. When the two
rise the evening of Tuesday the 13th, the Moon will therefore be
just to the west of the star, while the night of Monday the 14th,
the situation will be reversed. Almost exactly three days after
the Antares encounter, the brightened Moon takes on much brighter
Jupiter, passing three degrees to the south of the planet the
morning of Thursday the 17th, less than a full day before the full
phase. As the Moon climbs the sky the night of Wednesday the 16th,
it will appear to the west of the planet, while again the night of
Thursday the 17th, it will have flipped to the east of Jupiter.
Mars -- visible in
evening twilight -- begins the week just to the south of somewhat
Saturn, both lying in Leo to
the east of Regulus. Moving
rapidly, Mars will quickly shift to the east of the other two, much
more distant Saturn (4.5 times farther away than Mars) moving
easterly at a much slower pace. By the end of the week, the red
planet will be nearly four degrees to the east of the ringed one.
As Mars and Saturn descend the twilight sky, both gone from view by
10:30 PM or so (Daylight), Jupiter, which now rises before sunset,
makes its glorious appearance in the far southeast still to the
northeast of classical Sagittarius.
While the bright Moon blocks most of the constellation from view,
Jupiter shines on. And whatever happened to
Venus? Having passed superior conjunction with the Sun early
last June, the planet is slowly working its way up the western sky,
but is still too close to the Sun and horizon to be seen. Give it
another couple months.
Constellations differ greatly in
size. To the south of (and more or less parallel to) the Big Dipper's handle is a pair of
neighborly stars that make most of Canes Venatici, the Hunting Dogs, while north of Scorpius lies Serpens, whose two parts bracket giant Ophiuchus and take close to three
hours just to rise and set.