Photo of the Week. Mountains march off to meet the
blue sky (Atigun Pass, Brooks Range, Alaska).
Astronomy news for the two-week period starting Friday, October
5, 2007.
Skylights will resume its normal weekly schedule on October 19.
Thanks for your patience.
We begin the fortnight with the Moon in its waning crescent phase, which
thins as it heads toward dawn-rising and the new phase on
Wednesday, October 10. The remainder of the period is spent with
the Moon in the western sky as it waxes in
the crescent phase. First quarter is
finally reached the morning of Friday the 19th.
Watch as the waning crescent makes a particularly lovely journey
toward, then through, Leo. The
morning of Saturday the 6th finds the waning crescent above
brilliant Venus, while the following morning is even better with
the thinning crescent making a fine quartet with
Venus, the star Regulus, and,
almost touching the lunar cusp to the north, Saturn,
a configuration well getting up for. (The two planets pass conjunction
with each other the morning of Monday the 15th, when they are
but three degrees apart.) Then try locating the ultra-
thin crescent low on the dawn horizon the morning of Tuesday the
9th.
Next, flip to the western evening sky as the waxing crescent plows
through northern Scorpius. The
night of Sunday the 14th finds the Moon down and to the right of
Antares, while the following
evening, the Moon will make a fine triangle with Antares (now to
the west of the crescent) and Jupiter above
both of them. The Moon then takes off for Sagittarius, landing in the middle of the "Teapot" the
evening of Wednesday the 17th. While in the early waxing crescent,
on Saturday the 13th, the Moon goes through apogee,
where it is farthest from the Earth.
While Venus continues to dominate morning (rising at 3:30 AM
Daylight Time more or less in concert with much fainter Saturn),
Jupiter slips ever farther to the west. The giant planet, bright
in the southwest as the sky darkens, now sets around 9 PM, so enjoy
it early. It's replaced, however, by brightening Mars, which rises around 10:30
PM and is invading southern Gemini, where it will remain during the rest of the
year. Not far from the Summer
Solstice, the reddish planet transits the meridian near dawn very high to the south
as seen from mid-northern latitudes.
It may now be fall, but summer lingers on in the form of the famed
Summer Triangle. Made of Vega (in Lyra), Deneb (Cygnus), and Altair (Aquila), the Triangle now nicely helps fill evening's
northwestern sky. Within it lie prominent Sagitta (the Arrow) and dim modern Vulpecula (the Fox), while to the east of the Triangle
find the large four-star box that makes the Great Square of Pegasus.