December 1, 2015
The Night Sky:
Look for the Geminids meteor show in mid-December
By GERRY LEBING
First, kudos to the Cape Hatteras Electric Cooperative on its recent announcement of a new initiative to reduce light pollution!
According to Susan Flythe, executive vice-president and general
manager, the CHEC board of directors voted at its Nov. 19 meeting
to approve the replacement of the 100-watt and 250-watt HPS
(high-pressure sodium) security lights with LEDs beginning in 2016.
"The opportunity to be responsive to dark sky issues combined with
maintenance cost savings and REPS compliance were compelling arguments
for changing the lights,” Flythe told me in an e-mail.
CHEC provides outdoor security lights to its customers who are changed a monthly rate for them.
The most important feature of the new LED fixtures is that the shades
direct the light down to the ground. This initiative should
definitely help improve our night skies.
This is NGC7293, the Helix Nebula.
is often called the "Eye of God" or "Eye of Sauron" Nebula -- if
you’re a fan of "The Lord of the Rings." Two years ago, I got a
very poor shot of NGC 7293 that took about two hours to capture.
It is only visible through a telescope for a short period each
year. When visible, it is fairly close to the southern horizon
and is obscured by the any lights from southern cities or towns.
This image is the result of stacking 40 images together to get
enough information to reveal the nebula. Each individual image took 75
seconds to collect on the telescope. I took about 80 exposures
and used the best ones for the final product. After stacking, I
had to perform some very detailed image processing to get to the final
result. So, this image took two years of waiting for a clear,
calm night at the proper time of year, about three hours of intense
telescope time and 10 hours of image processing.
DECEMBER SKY WATCHING
The Geminids meteor shower will peak on the nights of Dec. 13-14 and
14-15. You can expect to see as many as 100 meteors per hour. The
best viewing will start about 9 p.m. and run through the night until
dawn. The meteors will appear to originate from the constellation
Gemini, the twins. Gemini is easy find -- at 9 p.m., it will be
the two bright stars close together in the east-northeast sky.
Neptune and Uranus will be in the night skies. On an
exceptionally clear night, you might be able to see Uranus with the
naked eye, but you need strong binoculars or a telescope to see
Mercury will be visible near the southwest horizon right after sundown for the second half of December.
Jupiter, Mars, and Venus will all be visible near the eastern horizon in the early morning hours.
The constellation Orion will be one of the dominant sights of the night
skies in December. In the beginning of the month, it will rise in
the east around 7:30 p.m. By the end of the month, it will be rising at
sundown! M42, the Orion Nebula, is visible to the naked
eye. It is located around the second star in the sword of
Orion. If you have trouble making it out, grab a pair of
binoculars. I am sure you will enjoy the sight.
This is an 11-second image I took of M42 in November.
Last Quarter: Dec. 3
New Moon: Dec. 11
First Quarter: Dec. 18
Full Moon: Dec. 25
"Stacking" is a technique used in astrophotography to reduce the
signal-to-noise ratio when processing images of deep-space
objects. The basic theory is the signal from an object is
constant, while noise is random. Stacking programs analyze a
series of images to find and remove the random noise.
Lebing is a retired computer scientist with the U.S. Geological Survey
in Washington, D.C. He has visited Hatteras Island since the
mid-1970s. He and his wife, Karen, have owned property here for several
years and moved to their home in Waves full-time in 2013.
Astronomy is a subject that Gerry says he has always been interested in
and one that he pursues seriously -- he's built an small observatory
next to his house. You can send him questions about the night sky
through e-mail, [email protected].)