Hello again rambler:
Another fascinating question. :-)
Well, to start with, you are right in saying that you cannot go out at
night (even in the darkest of regions) and see the Galactic Center
with the naked eye, because a massive amount of galactic dust and gas
obscures the visible light coming from that region.
However, therein lies the key to your question of why scientists can
get such a clear view of the Galactic Center. There are *many* other
types of light and radiation coming from space than just the band
visible to the human eye.
Gene Smith's Astronomy Tutorial - The Structure of the Milky Way
URL: http://cassfos02.ucsd.edu/public/tutorial/MW.html
Quote: "What lies at the center of our Galaxy? Again, dust obscures
the visible light from us and we must use radio and infrared
observations to elicit the nuclear properties of the Galaxy."
Besides radio waves and infrared light, scientists also use X-rays and
gamma-rays to get "pictures" of what the Galactic Center is like. It
is very likely that the pictures you saw on TV were using one of these
measurement methods, which computers would then translate into a
visible representation that could be used for illustrative purposes.
Similar information can be found at other sites:
Journey to the Center of the Galaxy
URL: http://www.astro.ucla.edu/~tanner/gcintro.html
Quote: "The Galactic Center is obscured from our view by a prodigious
amount of absorbing gas and dust that lies along the 25,000 light year
(2.5X10^17 mile) distance from there to our Sun. As a result, most of
what we know about this part of our galaxy comes from observations of
radio and infrared radiation, whose long wavelengths can pass through
the dense absorbing medium and reach our telescopes on Earth."
The above UCLA website also has a good map of where the Galactic
Center is actually located in the night sky. (Scroll to the very
bottom of the page.)
"...a map so you can find the Galactic Center yourself. It is located
near the constellation Sagittarius along with a number of pretty
nebula including the Trifid Nebula (M20) and Eagle Nebula (M16). Both
of these Messier objects can be viewed nicely with binoculars.
Sagittarius, which is close to Scorpio, is visible primarily during
the summer months from April-August."
Some other interesting sites on the Galactic Center include:
A Low-Frequency Atlas of the Galactic Center
URL: http://rsd-www.nrl.navy.mil/7213/lazio/GC/
UCLA Galactic Center Group
URL: http://www.astro.ucla.edu/~jlu/gc/
A Galactic Center Mystery
URL: http://science.nasa.gov/headlines/y2002/21feb_mwbh.htm
Search Strategy (on Google):
* center "milky way"
* "milky way" "galactic center" viewing
* "galactic center"
I hope this helps!
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