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.

2001 September 14
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Cold Dust in the Eagle Nebula
Credit: ESA, ISO, ISOGAL Team

Explanation: Stars are born in M16's Eagle Nebula, a stellar nursery 7,000 light-years from Earth toward the constellation Serpens. The striking nebula's star forming pillars of gas and dust are familiar to astronomers from images at visible wavelengths, but this false-colour picture shows off the nebula in infrared light. Data from ESA's Infrared Space Observatory satellite (ISO) was used to construct the detailed two colour image, dominated by infrared emission from clouds of interstellar material at temperatures below -100 degrees Celsius. Blue colours highlight emission thought to indicate the presence of complex carbon molecules, known on planet Earth as PAHs, while red colours trace emission from cold, microscopic dust grains. Hot young stars are formed as this frigid material condenses under the influence of gravity. Once begun, the process takes only tens of thousands of years for truly massive stars and up to tens of millions of years for low mass stars like the Sun.

Tomorrow's picture: Infrared Moon


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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.