Photo of the Week.Cloud shadows create a stunning
sunburst.
Astronomy news for the two weeks starting Friday, December 19,
2014.
The next Skylights will appear Friday, January 2, 2015. Thanks
for your patience. Best wishes for a merry and happy holiday
season.
We begin with the Moon as a thin waning
crescent visible in morning twilight as it approaches new on
Sunday, December 21, in celebration of the passage of the Sun over the winter solstice at 5:03 PM CST (6:03
EST, 4:03 MST, 3:03 PST), which takes place the same day. Winter
then officially begins as the Sun bottoms out at its extreme
southerly position in Sagittarius,
23.4 degrees below the celestial
equator, giving minimum heat to the northern hemisphere as
well as the shortest day and longest night. The Sun will
thereafter begin climbing back north toward the Vernal Equinox and the first day of
spring. The morning of Saturday the 20th, the crescent will
appear down and to the left of Saturn.
After new phase, the Moon advances in the evening as a waxing crescent, appearing nicely in
western twilight. Look for it above Venus the
evening of Tuesday the 23rd, more of less between the bright
planet and Mars. The Moon
appears to the right of Mars Christmas Eve, when the Moon also
passes perigee, its
point closest to Earth. Christmas night, the growing crescent
will be up and a bit to the left of Mars. The waxing crescent
terminates at first quarter on
Sunday the 28th about the time of its daylight rise in North
America, and it then enters the waxing
gibbous phase, full Moon not reached
until January 4, 2015. The Moon passes north of Neptune on
Friday the 26th and just north of Uranus on Sunday the 28th, the planet
ceasing retrograde
motion on Monday the 22nd.
It's all about Jupiter now, the giant planet rising brightly in far western
Leo to the west of Regulus just before 9 PM at the
beginning of our session, an hour earlier by the end of it,
Jupiter crossing the meridian to the
south between 3 and 4 AM. But watch out, as Venus is coming up to
rival it, our planetary neighbor now appearing low in southwestern
twilight. In between we have Mars, which, still first magnitude,
is good until the usual 8 PM as it treks through Capricornus. Shortly after
Jupiter transits to the south and about an hour before dawn,
Saturn rises just to the northwest of Scorpius's three-star head.
While some of the summer stars, including Cygnus and Lyra (with
bright Deneb and Vega), are still with us early-on in
the northwest, the fall stars, including Pegasus with its Great Square and the rest of the Andromeda gang, dominate the
early evening as we await the stars of winter, mighty Orion rising as twilight fades.
Look also in the northwest for bright Capella in the pentagon-shaped Auriga, the Charioteer.
