Astronomy news for the week starting Friday, June 20, 2008.
Skylights now resumes its normal weekly schedule.
Our single week begins with the Moon now in its waning gibbous phase, which leads it toward
third quarter, which will be passed on the
morning of Thursday, June 26, about the time the Moon crosses the
meridian to the south, making it
possible to see the third in near-perfection. Having passed its
low point near full phase,
the Moon is now gliding up the ecliptic to the north, with third
quarter taking place near the Vernal
Equinox in western Pisces.
On Monday the 23rd, the waning
gibbous passes north of Neptune, occulting it
from the far northlands, then passes several degrees north of Uranus on Wednesday
the 25th.
Venus invisibly passed conjunction with the Sun. This week yields
more of the same, with Uranus beginning
retrograde motion the morning of Friday the 27th, thus making
it just within this week's period. At mid-sixth magnitude, Uranus
is actually visible to the naked eye just south of the Circlet of Pisces, but only from the
darkest of skies and certainly not with the Moon out. Distant Pluto then comes into
opposition with the Sun on Friday the 20th. Though the high tilt
of Pluto's orbit has for some time kept it far north of the
ecliptic, it has now at least returned to the Zodiac, and it now resides in far
northwestern Sagittarius. With an orbital period of 248 years, it
moves on the average but just under 1.5 degrees per year, as
opposed to Mars's
current motion of some half a degree per DAY.
Speaking of which, the red planet is still nicely visible moving
easterly through western Leo, as it
closes in on Regulus and Saturn just a bit to
the east of it, the trio to make a fine sight, if they are not
doing so already. Mars now sets around 11:30 PM Daylight Time,
just half an hour before Saturn (just to the east of Regulus) goes
down. Well before they both set, Jupiter, rising in
mid-twilight around 9:30 PM, is well up, the giant planet now
crossing the meridian low to the south around 2 AM
Daylight.
Saving the best for near-last, it's Earth, though,
that makes the news, with the Sun passing the Summer Solstice at the Gemini-Taurus border
at 6:59 PM Central Daylight Time (7:59 Eastern, 4:59 Pacific) with
the Sun still up in the west in most of North America, allowing you
to enjoy the formal beginning of northern summer (without of course
directly looking at the Sun).
Summer in a sense also begins Milky
Way season for northerners. By true local midnight (1 AM
Daylight), the Winter Solstice in
Sagittarius (opposite the Summer Solstice) crosses the meridian,
allowing the glorious Milky Way in Sagittarius and Scorpius to shine forth low in the
southern skies.
