Photo of the Week. A flowing tree frames a rising
daylight waxing crescent Moon just 4.5 days old.
Astronomy news for the two weeks starting Friday, August 28,
2015.
The next skylights will appear September 11, 2015.
We open our two-week period with the Moon just shy of full, that phase passed
during the day on Saturday, August 29. The Moon will thus rise in
the end stage of its waxing gibbous phase
the night of Friday the 28th and be barely in the waning gibbous phase as it rises just past sunset
the evening of Saturday the 29th. The gibbous Moon then continues
to wane until third quarter is reached
the morning of Saturday, September 5, after which our companion
slims as a waning
crescent until our fortnight runs out. The waning gibbous
passes close to Uranus on Tuesday the 1st (not visible in
North America) and then will appear very near Aldebaran in Taurus the night of Friday the 4th,
those in the northeastern
US actually seeing the Moon occult the star. The real winner will
be the morning of Thursday the 10th, when the Moon will make a
classic pairing with Venus, the planet just up and to the right of the
slim crescent. At the same time much dimmer Mars will appear to the left of
the crescent, the three almost in a row with the Moon in the
middle. Even the previous morning, Venus and the Moon will make a
pretty sight with the crescent well above the bright planet. On
Sunday the 30th, celebrating the coming September, the Moon passes
perigee,
where it is closest to
Earth.
As apparent from the above, Venus is starting to make a big splash
in the morning sky as it ends retrograde motion on
Saturday the 5th. Rising just before dawn, the brilliant planet,
the "morning star," rapidly climbs the morning sky. Mars is there
too, down and to the left of the Venus, but rises later and is
hard to spot, while Jupiter rises within
morning twilight and for now remains hard to see. Back in the
evening, Mercury
passes its greatest eastern elongation relative to the Sun on Friday the 4th, but sets within bright
twilight. Saturn is
better. To the right of Antares, in the middle of our
period the ringed planet does not set until around 10:30 PM
Daylight time, but you still need to look early, as at best it
appears not far above the southwestern horizon. Finally, as August
moves into September, Neptune passes opposition to the Sun.
Even with a bright Moon we can admire the Summer Triangle of Vega
in Lyra (fourth brightest star of
the sky, number two in the northern
celestial hemisphere) at the northwestern apex, Deneb in Cygnus (the Tail of the Swan but at the top of the
Northern Cross) at the northeastern apex, and Altair in Aquila at the southern point. At the other end of the
Northern Cross, marking the Swan's head, is Albireo, one of the prettiest double stars of the sky,
the pair shining blue against orange. South of Albireo is the
modern figure of Vulpecula, the
Fox, and farther down, just north of Aquila shoots the obvious
ancient pattern that makes Sagitta, the Arrow, Through Cygnus and Aquila flows
the Milky Way, which brightens
through Sagittarius and then for
mid-northerners drops out of sight below the horizon.
