Photo of the Week. The third of twelve in the "Flight
across Greenland," going from east to west above the fantastic
glacier and a river of ice. See full
resolution.
Astronomy news for the three weeks starting Friday, January 24,
2014.
The next Skylights will appear Friday, February 14. Thanks again
for your patience.
Another triple week means another three-fourths of the lunar phase
cycle. The Moon begins in the waning crescent phase just past
third quarter, which took place Thursday,
January 23. Slimming in the eastern sky, the crescent ends at new
Moon on Thursday the 30th. At about the same time, the Moon passes
perigee,
where it is closest to the Earth, which means exceptionally high
and low tides at the beaches (not that
too many in the north are swimming this time of year). Watch as
the crescent goes right under Saturn the
morning of Saturday the 25th then well above Antares of Scorpius the following morning. It will appear to the
left of the star the morning of Monday the 27th. The Moon then
takes on Venus, which is
now making a fine morning appearance, rising nearly an hour before
dawn by the end of our three-week period. The morning of Tuesday
the 28th, the thinning crescent will lie up and to the right of
Venus, while the following morning it will be barely visible down
and to the left of the planet. Brightening throughout these three
weeks, Venus hits maximum brilliance right at the end of the
period.
After new Moon, we see the waxing
crescent in western evening twilight. The evening of Saturday,
February 1, the crescent will pass above the innermost planet, Mercury. While
Venus claims the dawn, Mercury does its near best in evening, with
its greatest eastern elongation taking place the night of Friday
the 31st. The crescent then grows until the Moon hits its first quarter on Thursday, February 6, after
which it enters the waxing gibbous phase,
which ends at full Moon about
the time of Moonrise the night of Friday the 14th, just in time for
Valentine's Day. The waxing gibbous will pass a few degrees south
of Jupiter
the night of Monday, February 10, just a day before it passes its
apogee, where
it is now farthest from Earth, the difference between perigee and
apogee distances about 12 percent. Now high and low "spring" tides
are notably diminished.
While Mercury sets in western twilight and Venus just beats out
morning's dawn, the other three "ancient" planets sit in the
middle. First is Jupiter, which by late evening has already
crossed the celestial meridian high to
the south, still in Gemini and
almost as far north of the celestial
equator as it can get. Mars then rises
in Virgo an hour or so before
midnight, passing five degrees north of Spica on Tuesday, January 28. Saturn
then rises in Libra about 2 AM at
the start of our period, 12:30 AM at the end.
Sirius, in Canis Major, Orion's
larger hunting dog, dominates the evening's stellar sky. If you are
far enough south, look for the second brightest star, Canopus (in Carina, the Keel of the ship Argo), which shines 36 degrees south of Sirius.
Another 37 degrees farther south lies the South Celestial Pole, which is only
visible from south of the Earth's equator. Leaving winter aside,
with Leo well up in the east toward
midnight, we are getting our first tastes of the stars of spring.
Below it and Virgo stream the stars of Hydra, the Water Serpent, the longest constellation of the sky.
