New images and observations of the spectacular Orion Nebula have revealed normally hidden dusty regions and the odd behavior of very young active stars buried within them.
This penetrating view of the Orion Nebula ? a vast stellar nursery about 1,350 light-years from Earth ? comes from the Visible and Infrared Survey Telescope for Astronomy (VISTA), the newest addition to the European Observatory's Paranal Observatory in Chile.
Although the nebula is spectacular when seen through an ordinary telescope, what can be seen using visible light is only a small part of a cloud of gas in which stars are forming. Most of the action is deeply embedded in dust clouds and to see what is really happening astronomers need to use telescopes with detectors sensitive to the longer, infrared wavelength radiation that can penetrate the dust.
VISTA has photographed the Orion Nebula at wavelengths about twice as long as can be detected by the human eye.
As in the many visible light pictures of this object, the new wide field VISTA image shows the familiar bat-like form of the nebula in the center of the picture as well as the surrounding area.
At the very heart of this region lie the four bright stars forming the Trapezium, a group of very hot young stars pumping out fierce ultraviolet radiation that is clearing the surrounding region and making the gas glow. Observing in the infrared allows VISTA to reveal many other young stars in this central region that cannot be seen in visible light.
Looking to the region above the center of the picture, curious red features appear that are completely invisible except in the infrared. Many of these are very young stars that are still growing and are seen through the dusty clouds from which they form. These youthful stars eject streams of gas with typical speeds of about 450,000 mph (700,000 kph) and many of the red features highlight the places where these gas streams collide with the surrounding gas, causing emission from excited molecules and atoms in the gas.
There are also a few faint, red features below the Orion Nebula in the image, showing that stars form there too, but with much less vigor. These strange features are of great interest to astronomers studying the birth and youth of stars.