May 15, 2013
New ESO Image Shows Off Orion’s Fiery Clouds
Lee Rannals for redOrbit.com - Your Universe Online
The image shows off clouds of gas and interstellar dust at wavelengths too long for the human eye to see. These tiny dust grains block the view of what lies within and behind the clouds, making it difficult to observe star formation taking place in this region.
In order to circumvent the dusty area, astronomers need to use tools that are able to see at other wavelengths of light, such as the ESO-operated Atacama Pathfinder Experiment (APEX) in Chile. This telescope is located at an altitude of about 16,000 feet above sea level on the Chajnantor Plateau in the Chilean Andes, giving it a better perspective of our universe.
Part of the Orion Molecular Cloud can be seen in the new image, which is a rich melting pot of bright nebulae filled with hot young stars and cold dust clouds. This region stretches hundreds of light-years across and is located about 1350 light-years from us.
The large, bright cloud seen in the upper right of the image is the Orion Nebula, or Messier 42. This very popular nebula is visible to the naked eye as a slightly fuzzy middle "star" in the sword of Orion. Messier 42 is the brightest part of the stellar nursery where new stars are being born, and it is the closest site of massive star formation to Earth.
Dust clouds help form beautiful filaments, sheets, and bubbles as the result of gravitational collapses and stellar winds. These winds are streams of gas ejected from the atmosphere of stars, and they are capable of shaping the surrounding clouds into random shapes.
Astronomers use data from APEX, as well as images from the European Space Agency's Herschel Space Observatory, to search Orion for protostars. So far, scientists have been able to identify 15 objects that appeared much brighter at longer wavelengths than at shorter wavelengths.
Scientists writing in The Astrophysical Journal said in March that they were able to identify some of these youngest stars ever seen thanks to Herschel, APEX and NASA's Spitzer Space Telescope.
“Previous studies have missed the densest, youngest and potentially most extreme and cold protostars in Orion,” said Amelia Stutz, lead author of the paper. “These sources may be able to help us better understand how the process of star formation proceeds at the very earliest stages, when most of the stellar mass is built up and physical conditions are hardest to observe.”