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.
2000 September 19
Explanation: In the depths of the dark clouds of dust and molecular gas known as M17, stars continue to form. Visible in the above recently released representative-colour photograph of M17 by the New Technology Telescope are clouds so dark that they appear almost empty of near infrared light. The darkness of these molecular clouds results from background starlight being absorbed by thick carbon-based smoke-sized dust. As bright massive stars form, they produce intense and energetic light that slowly boils away the dark shroud. M17's unusual appearance has garnered it such nicknames as the Omega Nebula, the Horseshoe Nebula, and the Swan Nebula. M17, visible with binoculars towards the constellation of Sagittarius, lies 5000 light-years away and spans 20 light-years across.
Authors & editors:
Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA/GSFC
& Michigan Tech. U.