Skylights featured three times on Earth Science
Picture of the Day: 1
, 2
, 3
, 4
.
Photo of the Week.. Planet Earth: Snow adorns the
western US mountains.
Astronomy news for the week starting Friday, June 13, 2003.
Skylights' week starts with the nearly-full Moon,
the phase taking place the morning of Saturday the 14th about the
time of Moonset in North America. The night of Friday the 13th,
the Moon will therefore rise just before sunset, while the night of
the 14th it will rise just after. On Saturday June 21st, the Sun
will reach its most northerly point in its trek around the
ecliptic, when it passes the Summer
Solstice in Gemini. That
the full Moon is opposite the Sun and that it takes place just a
week before summer solstice passage makes this full Moon the most
southerly (and for northerners the lowest) of the year,
falling as it does between the classical figures of Scorpius and Sagittarius. The Moon then wanes through its gibbous phase as it approaches third quarter.
The week's biggest event is probably the approaching conjunction
between
Mars and Uranus, as the red planet prepares to pass three degrees
to the south of Uranus the night of Friday, the 20th. The
proximity of the two will make a fine way to find distant Uranus,
which is readily visible in binoculars (though the bright Moon will
make Uranus harder to see). Look for brightening Mars to rise in
the southeast around 12:30 AM daylight time. At the same time,
Venus and
Mercury approach each other for a conjunction that will take
place a mere three hours after Mars and Uranus make their
visitation, Mercury passing only half a degree south of Venus. The
passage will be difficult to see in morning twilight as the two
rise in mid-morning twilight only about an hour before the Sun. At
the same time, the pair plays games with Aldebaran in Taurus, Venus passing five degrees
north of the star on Wednesday the 18th, Mercury doing the same the
following day. The Moon of course gets into the act as well,
passing five degrees south of Neptune
on Tuesday the 17th, then just a bit to the south of Mars (and
five degrees south of Uranus) the night of Wednesday the 18th.
That the Moon is south of these planets reveals the tilt of its
orbit, which takes it as much as 5 degrees off the
ecliptic.
Jupiter, the lonely prize of the evening, rides the sky
ever lower as twilight falls, and now sets around 11:30 PM Daylight
Time. Now in direct motion, it is moving easterly in Cancer and heading toward brighter Leo, where it will reside next year.
As sky becomes dark, great orange Arcturus of Bootes (the Herdsman), the brightest star of the
northern hemisphere (though beating Vega by a mere 7 percent), rides the
sky high to the south. Near it lie two fine configurations of
stars. To the northeast find the semi-circle that makes the
constellation of Corona Borealis,
the Northern Crown. Immediately south of Corona Borealis, find a
small "X"-shaped configuration, an asterism that represents the
head of Serpens, the Serpent
that winds around great Ophiuchus, Serpens the only constellation that is in
two non-contiguous parts, western Serpens Caput (the head) and
eastern Serpens Cauda (the tail).
