Photo of the Week. The Sun sinks deeper within the
atmospheric haze layer as seen from 25,000 feet; compare with the
earlier picture.
Astronomy news for the week starting Friday, October 18, 2013.
Friday night, October 18, is the night of the full Moon, one almost as famed as the Harvest Moon and for the same
reason. This one is known as the Hunter's Moon. In the early
evening, the ecliptic (the
apparent path of the Sun, which is followed fairly closely by the
Moon) lies relatively flat against the eastern horizon. As a
result, the delay in Moonrise from one night to the next after full
phase is minimized, and the early evenings after sunset are flooded
with Moonlight, just right for the ancient hunt. This full Moon is
also eclipsed by the Earth's shadow. But
don't bother looking, as it's a
penumbral eclipse, and a partial one at that. In the penumbra
of a shadow, only a portion of sunlight is cut off. None of this
full Moon enters full shadow, and the effect is barely visible if
at all. A little dimming of the lower portion of the Moon might be
seen at maximum eclipse, which takes place at 6:50 PM CDT. The
Moon thereafter fades away in the waning
gibbous phase until it reaches third
quarter next week, the night of Saturday the 26th. Swinging up
along the Zodiac from Pisces (where it resides in the full
phase), it glides between the Pleiades and Aldebaran during midweek, then
finishes the week southwest of bright Jupiter.
Before anything, however, look to the southwest in the early
evening for brilliant
Venus, which makes itself quite obvious. This current
apparition as "evening star" has been a poor one. Now separating
itself from the end of twilight, the planet's visibility is rapidly
improving, as Venus does not set until shortly before 8:30 PM
Daylight time, after the sky has become fully dark. We then go
planetless for a few hours until Jupiter (the second brightest of
the planets) rises around 11 PM nicely placed in Gemini to the south of Castor and Pollux. Mars
joins the giant planet by rising about 2:30 AM. Having passed Regulus last week, Mars is now
gliding south of the classical figure of Leo, with the star to the west of it.
One of the better meteor showers of the year, the Orionids
, hits its peak the morning of Monday the 21st. In a dark sky
you might ordinarily see 20 or so an hour, possibly more, seeming
to emenate from the constellation
of Orion. But sadly, the sky is
awash with the light of a bright gibbous Moon, and except for the
hard core watcher who is hoping to catch some bright ones, it is,
like the eclipse above, is not worth much of a look. The Orionids
are the flakings of Halley's
Comet, whose orbit we approach twice a year. We'll come back
to it on the other side with early May's Eta
Aquarids.
Speaking of Orion, he is on full display in the early morning hours
before dawn. Just look to the south and about halfway up. With Sirius down and to the left, Procyon to the upper left, Jupiter
in Gemini with Castor and Pollux, and Mars in Leo with Regulus, the
whole gang makes for a super sight. Back in the evening, if you
are far enough south to see the Southern Cross, you might find second magnitude Alpha Pavonis, the luminary of Pavo, the Peacock, skimming the
horizon far below Altair.
