Physics Photo of the Week
The Trifid Nebula - Discussion by Nao Kimura
called Messier 20 is located about 5200 light years from
the Earth, in Sagittarius. It is right North of M8. And also, on its
North East direction, there is M21 open cluster. It is believed that it
was discovered in 1750. It is called “Trifid” because the Nebula looks
like it is divided into three parts. It is because there is a dark
nebula in front of M20. M20 has different characteristic in its North
part and its South part. In the North, it is a blue reflection nebula,
and in the South, it is a red emission nebula. A reflection nebula is a
nebula that is visible because its dark nebulas reflect other star’s
lights. An emission nebula is formed by many kinds of ionization gas
that radiate many different colors. It is also called HⅡ region due to
the ionized hydrogen. And there are about 120 of O-type young stars and
also Star clusters. Those stars radiate very intense ultraviolet
radiation that ionizes the gas in the nebula.
The photo was taken by students in the Contemporary Astronomy class on
August 20, 2010 by Karlyn
Hunt, Casey MacMillan, Jake Gerry,
Nao Kimura, and Laetitia Mead.
Photo of the
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