The Great Orion Nebula, one of the perennial favorite scenic wonders of the night sky has begun to reveal its innermost secrets. A new dramatic image of this giant gas cloud has been showcased by the European Southern Observatory’s new VISTA survey telescope. The telescope’s huge field of view can show the full splendor of the whole nebula and VISTA’s infrared vision also allows it to peer deeply into dusty regions that are normally hidden and expose the curious behavior of the very active young stars buried there.
The Orion Nebula is a vast stellar nursery lying about 1,350 light-years from Earth. 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 wavelength radiation that can penetrate the dust. VISTA has imaged the Orion Nebula at wavelengths about twice as long as can be detected by the human eye.
VISTA — the Visible and Infrared Survey Telescope for Astronomy — is the latest addition to ESO’s Paranal Observatory. It is the largest survey telescope in the world and is dedicated to mapping the sky at infrared wavelengths. The large (4.1-meter) mirror, wide field of view and very sensitive detectors make VISTA a unique instrument. This dramatic new image of the Orion Nebula illustrates VISTA’s remarkable powers.
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 fascinating 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. However, observing in the infrared allows VISTA to reveal many other young stars in this central region that cannot be seen in visible light. These youthful stars eject streams of gas with typical speeds of 700,000 km/hour 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.
Below is a cool video of the new look at Orion…
- Adapted from an ESO news announcement
Doorstep Astronomy: You can take a gander at this star factory for yourself with nothing more than your unaided eyes – even from light polluted suburbs! Just face towards the southern sky all evening long and look for Orion constellation’s distinctive row of three stars. This trio marks the belt of the mighty hunter. Just below the belt is Orion’s sword – which is a near vertical row of another three fainter stars.
Look closely at the middle star, and you will notice that it looks kind of fuzzy compared to the ones beside it. You have found Orion’s nebula – a giant cloud of gas and dust nearly 1400 light years away from us.
Binoculars and even a small telescope will begin to reveal the cloud’s beautiful flower-like structure composed of a tiny, tight cluster of blue-white stars surrounded by a grey-green mist. The French comet-hunter Charles Messier made an accurate sketch of its main features in the mid-eighteenth century and gave it the number 42 in his famous catalogue.
Tags: M42, nebula, Orion
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