Astronomy news for the week starting Friday, June 28, 2013.
The night of Friday, June 28, finds the Moon at the end of its waning gibbous phase, which ends at third quarter the night of Saturday the 29th
about the time of Moonrise in North America. With the Sun just past
the Summer Solstice in classical Gemini, the third quarter will be
a bit to the east of the Vernal
Equinox in Pisces and a few
degrees northwest of
Uranus. Though in a dark sky the planet is visible to the naked eye, the
bright Moon will render its viewing hopeless. The remainder of the
week finds our companion slimming as a waning
crescent, the phase ending at new Moon next week. The morning
of Wednesday, July 3, the rising crescent will appear to the right
of the Pleiades in Taurus, while the following morning
it will be below the cluster. The morning of
Friday the 5th, look for it just to the left of Aldebaran.
Venus viewing is improving in the twilight of the evening.
Look in bright dusk for a bright "star" in the west northwest just
above the horizon. Still elusive, the planet sets by 10 PM
Daylight Time, half an hour before twilight comes to a close. The
planetary sky is then saved by Saturn. Invisibly crossing
the meridian to the south at sunset,
the planet is well into the southwestern sky by the time you can
see it, still in eastern Virgo a
dozen degrees to the east of Spica,
the two still making a nice, if distant, pair. We get to see the
planet until a couple hours after midnight, when it sets. As June
turns to July, Pluto passes
opposition with the Sun. A creature of the distant
Kuiper Belt of leftover debris, the faint telescopic ball of
rock and ice is difficult to find amongst the myriad stars of Sagittarius's Milky Way.
Closer in, we highlight Earth, which on the morning of Friday, July
5, passes its orbital aphelion where it is farthest from the Sun,
94,509,959 miles (152.1 million km), 1.7 percent farther than
average. Given the heat of summer, distance from the Sun clearly
has no relation to the seasons, which are caused
entirely by the 23.4 degree tilt of the Earth's axis against the
orbital perpendicular.
The night sky is home to various mythical people (Andromeda, Cassiopeia, Hercules),
two horses (Pegasus and Equuleus), and two centaurs that fall
in between. As darkness descends, look just above the southern
horizon for the bright stars of Centaurus (the eponymous Centaur), then around local
midnight again to the south for Sagittarius, the Archer (marked by the upside-down
"sgr-t.html">Little Milk Dipper), who holds the center of the Galaxy within his grasp.
