Physics Photo of the Week
September
7, 2007
The Milky Way Sagittarius Region
Get away from
bright city lights and you get
to the "bright lights" of the Milky Way. This view, photographed
in northeastern Vermont in July 2007, looks south towards the center of
our galaxy.
What we see in the Milky Way are millions of stars, so distant and so
numerous that they appear to be merged into a continuous "cloud" of
stars. In addition to the cloud of stars, we can see clouds of
interstellar dust blocking some of the starlight. In fact, we
cannot see the center of our galaxy due to the interstellar dust.
Radio astronomy has detected emission from the center of our galaxy
near the center of this photo. Please see the PPOW
for November 11, 2005 for a photo of a distant galaxy that shows
the dust.
Sagittarius appears as a "Teapot"
asterism outlined in the image at right. Scorpius, "the Scorpion"
is also outlined. The bright red star Antares is easily
visible. Scorpius is being visited this year by the planet
Jupiter. Next year (2008) Jupiter will be close to the
Teapot. At the latitudes where this photo was made, 45 deg N, the
horizon and mountains hide part of the tail of the scorpion. At
Warren Wilson (35 deg N) all of the scorpion is visible.
Dark skies are disappearing from many parts of the world due to
increasing light pollution from city lights. The ability to see
the stars, planets, and Milky Way should be a right for all world
citizens. Most outdoor lighting wastes much light into the sky,
wastes energy, and is surprisingly ineffective for outdoor
illumination. With care, outdoor lighting systems can be designed
with shields and reflectors to concentrate the light onto the ground,
minimizing the light cast into the sky, use less power, and allow the
astronomical objects to be viewed from properly lit urban areas.
Photo details. The image was made with a Canon A360 digital
camera set at an ISO rating of 800. 20 images of 15 seconds each
were aligned and co-added using MaximDL software. The contrast
and color saturation was enhanced to show the highly colorful region.
Physics
Photo of the
Week is
published weekly during the academic year on Fridays by the Warren
Wilson College Physics
Department. These photos feature an interesting phenomena in
the world around us. Students, faculty, and others are invited to
submit digital (or film) photographs for publication and
explanation. Atmospheric phenomena are especially welcome.
Please send any photos to dcollins@warren-wilson.edu.
Click
here to see the Physics Photo
of
the Week Archive.
Observers are invited to submit
digital photos to:
