Last Quarter September 05
New Moon September 13
Full Moon September 27
below are notable astronomical events coming up for the month of
Mercury is in the evening sky at the start of September in the constellation
Virgo. On the evening of the 3rd, Mercury comes to its closest to
greatest eastern elongation at about 27 degrees separation from
the Sun! Unfortunately, most of this angular separation is closer
to parallel to the horizon, than it is to perpendicular –
in other words, Mercury’s apparent distance from the Sun in
the sky doesn’t translate to very much height above the horizon,
so it may still be somewhat of a challenge to spot Mercury after
sunset, unless you have a decently flat horizon in the west. Mercury
doesn’t keep that separation for long! For the rest of the
month Mercury descends ever more rapidly into the glare of sunset
until inferior conjunction on the last day of the month.
Venus rises at a little after 5 a.m. in the constellation Cancer,
roughly 10 degrees SSE of the planet Mars at the beginning of September.
The waning crescent Moon makes a delightful pairing with Venus on
the morning of the 10th. Venus crosses over into the constellation
Leo on the 24th of the month and by the 30th is rising at about
3:45 a.m. as a prominent “morning star!”
At the beginning of September, Mars rises at about 4:45 a.m. in
the constellation Cancer, about 10 degrees NNW of the much brighter
planet Venus. Mars forms a line with the waning crescent Moon and
Venus on the morning of the 10th of the month. Thereafter, Mars
rises slightly earlier in the morning for the rest of the month,
and rises at slightly before 4:30 a.m. by month’s end.
Jupiter is deep in the pre-dawn solar glare at the beginning of
September, just having come to solar conjunction at the end of last
month in the constellation Leo. By about the last third of the month,
Jupiter finally begins rising early enough to be seen before the
light of dawn hides its light. By the end of the month, Jupiter
rises right at 5 a.m.
Saturn begins September modestly high in the SW in the constellation
Libra, just a couple of degrees west of the stars of the head of
Scorpius the scorpion. On the evening of the 18th, the waxing crescent
Moon passes only about 3 degrees away from the Ringed Planet for
a nice celestial meeting between solar system objects! All month
long, Saturn has been resuming normal, westward annual motion with
respect to the stars and ends the month setting at the edge of Libra
slightly after 9:30 p.m.
Uranus rises in the constellation Pisces all month long at a little
after 9:20 p.m. The nearly Full Moon bypasses closest on 9/28, and
at the end of the month rises a little after 7:20 p.m. Opposition
is next month! It is possible to observe Uranus through binoculars
or telescopes as a pale blue, steadily-shining “star”
in binoculars, and a small telescope at moderate-to-high power (about
75x or more) will reveal its disc (magnitude 6.05, and 3.7 arc-seconds
Neptune is just hours past opposition on the 1st of the month in
the constellation Aquarius, so during the entire month of September,
Neptune will be up virtually all night long! The waning gibbous
Moon bypasses closest on the night of 9/25. Neptune appears as a
slightly deeper blue-hued “star” in binoculars than
Uranus normally does, and also much less bright. A telescope will
barely reveal a very small disc (magnitude 7.65, and 2.4 arc-seconds
on 9/30) at high power (150x or more).
Ceres is already above
the horizon after sunset at the beginning of September in extreme
SE Sagittarius, far from the Teapot asterism. Another way to describe
its position is that it is just SW of the constellation Capricornus.
The Moon makes its closest approach on the nights of 9/22 and 9/23,
and it’s not particularly close – perhaps up to 15 degrees
separation on either night. By month’s end, it is in modest
retrograde motion in Sagittarius, nearly at meridian at about an
hour after sunset. An observer will be able to view Ceres with a
telescope (although a detailed star chart will be necessary to pinpoint
its position), although far from glaringly, and even then Ceres’
disc is too small to be seen through any but the largest professional
ground-based telescopes. Ceres should appear as a “dot”
of a star, much like Pluto, only it will be visible with MUCH more
modest viewing equipment! It is actually dimmer than Neptune is
on 9/30 at magnitude 8.0.
Pluto is in the constellation
Sagittarius for the month of September, and is nearly at meridian
about an hour after sunset at the beginning of the month. The first
quarter Moon makes its closest pass on the evening of 9/21, and
Pluto finishes the month sat a little bit past meridian an hour
after sunset. However, seeing it in a backyard telescope is another
matter…! The icy dwarf planet is only visible as a very modest,
slight “dot” of a star in a telescope of at least 8”-10”
aperture. A very detailed star chart (as well as a great amount
of patience and endurance!) is vitally necessary in order to spot
it! Pluto glows feebly at magnitude 14.17.
Lunar Eclipse on the Evening of September 27!
On the night of September
27, Farmington will be treated to a total lunar eclipse immediately
after sunset! The umbral, or deep-shadow, part of the eclipse will
begin at 7:07 p.m. local time, when the leading edge of the darkest
part of the Earth’s shadow will obscure the face of the Moon!
At 8:11 p.m. all of the Moon will be in the Earth’s shadow,
beginning the phase of totality. The Moon, however, will probably
not be all dark - it will likely appear to be a reddish, or even
orange, color! This has to do with the fact that the Earth’s
atmosphere acts like an eyeglass lens and will bend light rays near
the red end of the spectrum so that they project onto the Moon slightly!
The midpoint of the eclipse will be at 8:48 p.m. and the Moon will
begin to come out of the Earth’s shadow, ending totality,
at 9:23 p.m.! The umbral eclipse will end at 10:27 p.m., when the
trailing edge of the Earth’s shadow moves off the Moon’s
The planetarium will
hold a special telescopic observing session of part of the eclipse
at the college in the courtyard behind the planetarium, which will
begin at 8:00 p.m. and end at 9:30 p.m., weather permitting, of
course. The planet Saturn will be visible to the naked eye, although
very low over the western horizon at this time, and telescopic viewing
of distant giant planets Uranus and Neptune may be possible! The
event is free of charge and open to the public! If the weather is
cloudy or rainy, however, the observing will have to be cancelled.
For more information,
please call David Mayeux at 566-3361.
Showers - http://amsmeteors.org/showers.html
Comets - http://cometography.com/current_comets.html
events - http://www.skyandtelescope.com/observing/highlights