April 20, 2009
Project Reveals Super Active Orion Nebula
Astronomers have completed the most comprehensive census of the star formation surrounding the Orion Nebula.
Using the United Kingdom Infrared Telescope (UKIRT) in Hawaii, the IRAM Millimeter-wave Telescope in Spain, and the orbiting Spitzer Space Telescope, astronomers have uncovered a much busier scene than previously considered in and around Orion, some 1300 light years away from Earth.
They found that a stellar nursery exists behind the constellation, and can be vaguely seen through the fuzzy patch around Orion's sword, known as the Orion Molecular Cloud. Astronomers characterize the region as chaotic and somewhat overcrowded, with young stars emitting gas in every direction.
Spanning from above Orion's head to far below his feet, the Orion Molecular Cloud is more than 20 times angular the size of the full moon. It has become the subject of several studies in the past.
But the recent study is the first to present such a complete study of the young stars, the cloud of gas and dust from which they are being born, and the spectacular supersonic jets of hydrogen molecules being launched from the poles of each star, astronomers from the three facilities said.
Due to its thickness, the molecular field is mostly to blame for keeping the "action" hidden from plain sight. The Orion nebula provides just a glimpse of what is truly going on.
Astronomers required the ability to observe at wavelengths beyond the reach of the human eye. They combined the resources of UKIRT, the Spitzer Space Telescope, which works at even longer "mid-infrared" wavelengths, and the IRAM radio telescope, which operates beyond the infrared at short radio wavelengths.
"This spectacular dataset demonstrates the power of survey telescopes like UKIRT. With on-line access to data from other telescopes around the world, and the ease with which one can communicate with collaborators across the globe, massive projects like the Orion study are very much the future of astronomy," said Dr. Andy Adamson, Associate Director at the UKIRT.
"Regions like this are usually referred to as stellar nurseries, but we have shown that this one is not being well run: it is chaotic and seriously overcrowded," said Dr. Chris Davis of the Joint Astronomy Center in Hawaii.
"Using UKIRT's wide field camera (WFCAM), we now know of more than 110 individual jets from this one region of the Milky Way. Each jet is traveling at tens or even hundreds of miles per second; the jets extend across many trillions of miles of interstellar space. Even so, we have been able to pinpoint the young stars that drive most of them."
"Star formation research is fundamental to our understanding of how our own sun, and the planets that orbit it, were created," Thomas Stanke of the European Southern Observatory in Garching, Germany, who worked on the study, said in a statement.
"Many of the stars currently being born in Orion will evolve to be just like the sun. Some may even have Earth-like planets associated with them."
The new study's findings will be presented at the European Week of Astronomy and Space Science (NAM 2009) at the University of Hertfordshire on Monday.
Image 1: This spectacular image combines observations from the United Kingdom Infrared Telescope and the Spitzer Space Telescope. It shows just a small portion of the region surveyed. In this figure, parts of the Orion Molecular cloud are illuminated by nearby stars and therefore glow an eerie green color. The jets punch through the cloud and can be seen as a multitude of tiny pink-purple arcs, knots and filaments. The young stars that drive the jets are usually found along each jet and are colored golden orange. Credit: UKIRT/JAC, Spitzer Telescope.
Image 2: A close-up view of a spectacular jet (seen in red) popping out of a busy region of star formation in Orion. All of the red wisps, knots and filaments are in fact associated with jets from young stars, which in this figure are colored orange. These data were acquired with the Wide Field Camera (WFCAM) at the United Kingdom Infrared Telescope. Credit: UKIRT/JAC.
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