Photo of the Week. The lineup of planets and stars on
July 1. From lower right diagonally toward middle left, find
Venus, Regulus, Mars, Saturn, and
Porrima (Gamma Virginis). Spica is off the picture to the left,
while Leo roars above them all.
Astronomy news for the week starting Friday, July 16, 2010.
This is the week of the first quarter
Moon, the phase reached the morning of Sunday the 18th with the
Moon well out of sight. During the evenings leading up to it, we
get to admire the fat waxing crescent.
The remainder of the week then belongs to the brightening waxing gibbous, full
phase not hit until Sunday the 25th. As our week begins, the
evening of Friday the 16th look for Saturn well up and to the right of the
Moon, whose orbital tilt takes it to the south of the ecliptic and
to the run of planets that still appears in the evening sky. Then
the following night, that of Saturday the 17th, the not-quite-
first-quarter (as close as we can see this round) will appear to
the southwest of Spica in Virgo. Keep watching then, as on
the night of Wednesday the 21st the Moon will appear just to the
east of Antares in Scorpius.
And speaking of the run of planets, the early evening sky still
holds our three gems. Venus, now well east of Regulus, starts it off low but very
bright in the evening western sky, the planet now setting just a
hair after the end of twilight. Up and to the left of it, find
reddish
Mars, which provides a fine color contrast and sets only half
an hour after Venus goes down. Higher yet, up and to the left of
Mars, Saturn completes the string, the ringed planet (still just
north of the autumnal equinox to the west of Virgo's Spica) setting just behind
Mars.
On the other side of the sky, Jupiter holds court.
Almost directly opposite Saturn, the giant of the Solar System
unmistakably rises in western
Pisces around 11:30 PM Daylight Time. Moving only slowly
against the stellar background just to the east of the Vernal Equinox, Jupiter passes a
milestone by entering
retrograde (westerly) motion on Friday the 23rd, as the Earth
prepares to pass between it and the Sun.
With summer full upon us, we are losing the spring constellations to the western sky, the
Dipper now dipping into the
northwest. Arcturus, though,
still colorfully shines south of it, while blue Spica of Virgo is
yet farther down, at least until late evening. Arcturus, the
luminary of the northern hemisphere, sits at the southern end of
kite-shaped Bootes, the Herdsman.
To the east of it, look for the semi-circle that makes Corona Borealis, the Northern Crown.