Astronomy Picture of the Day
Discover the cosmos!
Each day a different image or photograph of our fascinating universe is
featured, along with a brief explanation written by a professional
astronomer.
July 23, 1995
M20: The Trifid Nebula
Credit: Hopkins Observatory, Karen Gloria
Explanation:
The vivid blue and violet colours present in the Trifid Nebula result
from the abundance of young stars there.
The light from young massive stars is quite blue and has the ability
to remove electrons from surrounding gas. When these electrons re-combine
with the gas, radiation rich in blue and violet light is emitted. Some
of the nebula's light also results from the reflection of star light off
of extremely small carbon specks known as 'dust'.
This object is known to astronomers as M20 - the twentieth object on
Charles Messier's
list of diffuse sky objects.
This image was taken with a 6-inch refracting
telescope.
For more information on M20 see The Electronic Universe Project's
write-up.
Many images of Messier objects can be found in
The Electronic Universe Project's
The Galaxy Gallery: Messier Objects.
Tomorrow's picture: M31: The Andromeda Galaxy
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Authors & editors:
Robert Nemiroff
(MTU) &
Jerry
Bonnell (USRA)
NASA Technical Rep.:
Jay Norris.
Specific rights apply.
A service of:
LHEA
at
NASA/
GSFC
&:
Michigan Tech. U.