In one of the most detailed astronomical images ever produced, NASA's Hubble Space Telescope is offering an unprecedented look at the Orion Nebula. This turbulent star-formation region is one of astronomy's most dramatic and photogenic celestial objects.

The crisp image reveals a tapestry of star formation, from the dense pillars of gas and dust that may be the homes of fledgling stars to the hot, young, massive stars that have emerged from their gas-and-dust cocoons and are shaping the nebula with their powerful ultraviolet light.

The new picture reveals large-scale structures never seen before, according to C. Robert O'Dell of Vanderbilt University in Nashville, Tenn. "Only with the Hubble Space Telescope can we begin to understand them," O'Dell said.

In a mosaic containing a billion pixels, Hubble's Advanced Camera for Surveys (ACS) uncovered 3,000 stars of various sizes. Some of them have never been spied in visible light. Some are merely 1/100 the brightness of stars seen previously in the nebula.

Among the stars Hubble spotted are possible young brown dwarfs, the first time these objects have been seen in the Orion Nebula in visible light. Brown dwarfs are so-called "failed stars." These cool objects are too small to be ordinary stars because they cannot sustain nuclear fusion in their cores the way our Sun does.

The Hubble Space Telescope also spied for the first time a small population of possible binary brown dwarfs — two brown dwarfs orbiting each other. comparing the characteristics of newborn stars and brown dwarfs in their natal environment provides unique information about how they form.

"The wealth of information in this Hubble survey, including seeing stars of all sizes in one dense place, provides an extraordinary opportunity to study star formation," said Massimo Robberto of the Space Telescope Science Institute in Baltimore, Md., and leader of the observations. "Our goal is to calculate the masses and ages for these young stars so that we can map their history and get a general census of the star formation in that region. We can then sort the stars by mass and age and look for trends."

Robberto will present his results on Jan. 11 at the 207th meeting of the American Astronomical Society in Washington.

The Orion Nebula is a perfect laboratory to study how stars are born because it is 1,500 light-years away, a relatively short distance within our 100,000 light-year wide galaxy. Astronomers have a clear view into this crowded stellar maternity ward because massive stars in the center of the nebula have blown out most of the dust and gas in which they formed, carving a cavity in the dark cloud.

"In this bowl of stars we see the entire star formation history of Orion printed into the features of the nebula: arcs, blobs, pillars, and rings of dust that resemble cigar smoke," Robberto said. "Each one tells a story of stellar winds from young stars that impact the stellar environment and the material ejected from other stars. This is a typical star-forming environment. Our Sun was probably born 4.5 billion years ago in a cloud like this one."

This extensive study took 105 Hubble orbits to complete. All imaging instruments aboard the telescope – the ACS, Wide Field and Planetary Camera 2, and Near Infrared Camera and Multi-Object Spectrometer – were used simultaneously to study the nebula. The ACS mosaic covers approximately the apparent angular size of the full moon.

November 20, 199512:00 AM (EST)

News Release Number: STScI-1995-45

Panoramic Hubble Picture Surveys Star Birth, Proto-Planetary Systems in the Great Orion Nebula

Astronomers are releasing today one of the largest pictures ever taken of the heavens with NASA's Hubble Space Telescope — a spectacular color panorama of the center of the Orion nebula, a star forming region located 1,500 light- years away in the constellation of Orion the Hunter.

Also being released today are five new close-up images of dust disks that may be embryonic solar systems around newborn stars in Orion. They may be similar to the disk our own solar system probably formed out of 4.5 billion years ago.

This seamless mosaic was assembled from 15 separate Hubble views of the vast nebula. Hubble resolves details of starbirth as small as four billion miles across — roughly half the diameter of our solar system. Though the Orion panorama sweeps a big piece of celestial real estate 2.5 light-years across, the nebula is so far away that Hubble's mosaic covers an area of sky only about five percent of the area covered by the full Moon.

The image was taken by C. Robert O'Dell of Rice University, Houston, Texas, who used the Hubble Space Telescope between January 1994 and March 1995 to survey the nebula. Hubble observing time was devoted to making this panorama because the nebula is a vast laboratory for studying the processes which gave birth to our own Sun.

Using computer image processing, O'Dell and graduate student Shui Kwan Wong spent several weeks precisely combining 45 Hubble visible-light snapshots (taken at different colors of light to yield a natural, "full color" panorama) to create 15 fields which were then aligned and overlapped to create the final mosaic.

Scattered among the 500 stars in this sweeping photo mosaic, are several newly identified disks of dust encircling stars. Mark J. McCaughrean of the Max-Planck-Institute for Astronomy in Heidelberg, in collaboration with O'Dell, identified these dark disks silhouetted against the bright background of the Orion nebula.

Though the first direct visual evidence for circumstellar dust disks in Orion was uncovered by Hubble in 1992, the latest images show, unequivocally, that these are truly disks tilted at different angles to Earth. One striking image — resembling an interstellar Frisbee — shows a disk tilted edge-on, hiding the young star at its center. (A detailed study of the disk images by McCaughrean and O'Dell will appear in the March 1996 issue of the Astronomical Journal.)

In addition, the survey yeilds 153 disks that are glowing due to a torrent of ultraviolet radiation from the nebula's central stars. The existence of so many young stars with protoplanetary disks mathematically increases the likelihood of other planetary systems, said the researchers. "It means the building blocks are there; however, it doesn't mean that planets will certainly form," O'Dell said. As a young star evolves either its disk material "is drawn into planets or it dissipates with time." Current theory suggests that planetary systems form around stars about one million years after they ignite. "That's just about the age we're seeing here," O'Dell noted.

A description of O'Dell's earlier Orion nebula findings appears in the December 1995 issue of the National Geographic Magazine, along with a poster-size image of the Orion nebula.

January 14, 199412:00 AM (EST)

News Release Number: STScI-1994-10

Hubble Probes the Great Orion Nebula

January 14, 1994: A NASA Hubble Space Telescope image of a region of the Great Nebula in Orion, as imaged by the Wide Field Planetary Camera 2.

This is one of the nearest regions of very recent star formation (300,000 years ago). The nebula is a giant gas cloud illuminated by the brightest of the young hot stars at the top of the picture. Many of the fainter young stars are surrounded by disks of dust and gas, that are slightly more than twice the diameter of the solar system (or 100 Astronomical Units in diameter).

October 4, 1990: This photograph, made with the Wide Field/Planetary Camera on NASA's Hubble Space Telescope, reveals the detailed structure of a newly discovered jet of material streaming away from a young star in the Orion Nebula.

October 4, 1990: This photograph, made with the Wide Field/Planetary Camera on NASA's Hubble Space Telescope, reveals the detailed structure of a newly discovered jet of material streaming away from a young star in the Orion Nebula.

October 4, 1990: Recent images made with the Wide Field Camera on NASA's Hubble Space Telescope have revealed the structure of a thin sheet of gas located at the edge of the famous "Great Nebula" in Orion, an estimated 1500 light years from Earth. Astronomers, who compare the appearance of this sheet of gas with that of a rippled window curtain, report that this emission traces the boundary between the hot, diffuse interior of the nebula and an adjacent dense cool cloud. The sheet is seen in light emitted by atoms of gaseous sulfur (shown in red in the photograph). This emission is strongest under conditions which are intermediate between those in the interior of nebula and those in the dense cloud.

ABOUT THIS IMAGE:

A NASA Hubble Space Telescope picture of a hypersonic shock wave (lower right) of material moving at 148,000 miles per hour in the Orion Nebula, a star-forming region 1,500 light-years away.

Studies of similar objects infer that such highly supersonic shock waves are formed by a beam of material coming out of newly formed stars.

The plume is only 1,500 years old. The image is 112 light-year across.

This color photograph is a composite of separate images taken at the wavelengths of the two abundant elements in the nebula: Hydrogen and Oxygen. The images were taken with HST's Wide Field and Planetary Camera (in wide field mode), on August 13 and 14, 1991.

A new image from NASA's Spitzer and Hubble Space Telescopes looks more like an abstract painting than a cosmic snapshot. The magnificent masterpiece shows the Orion nebula in an explosion of infrared, ultraviolet and visible-light colors. It was "painted" by hundreds of baby stars on a canvas of gas and dust, with intense ultraviolet light and strong stellar winds as brushes.

At the heart of the artwork is a set of four monstrously massive stars, collectively called the Trapezium. These behemoths are approximately 100,000 times brighter than our sun. Their community can be identified as the yellow smudge near the center of the composite.

The swirls of green were revealed by Hubble's ultraviolet and visible-light detectors. They are hydrogen and sulfur gases heated by intense ultraviolet radiation from the Trapezium's stars.

Wisps of red, also detected by Spitzer, indicate infrared light from illuminated clouds containing carbon-rich molecules called polycyclic aromatic hydrocarbons. On Earth, polycyclic aromatic hydrocarbons are found on burnt toast and in automobile exhaust.

Additional stars in Orion are sprinkled throughout the image in a rainbow of colors. Spitzer exposed infant stars deeply embedded in a cocoon of dust and gas (orange-yellow dots). Hubble found less embedded stars (specks of green) and stars in the foreground (blue). Stellar winds from clusters of newborn stars scattered throughout the cloud etched all of the well-defined ridges and cavities.

Located 1,500 light-years away from Earth, the Orion nebula is the brightest star in the sword of the hunter constellation. The cosmic cloud is also our closest massive star-formation factory, and astronomers suspect that it contains about 1,000 young stars.

The Orion constellation can be seen in the fall and winter night skies from northern latitudes. The constellation's nebula is invisible to the unaided eye, but can be resolved with binoculars or small telescopes.

This image is a false-color composite, in which light detected at wavelengths of 0.43, 0.50, and 0.53 microns is blue. Light with wavelengths of 0.6, 0.65, and 0.91 microns is green. Light of 3.6 microns is orange, and 8-micron light is red.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology, also in Pasadena. Caltech manages JPL for NASA.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. The Space Telescope Science Institute in Baltimore conducts Hubble science operations. The Institute is operated for NASA by the Association of Universities for Research in Astronomy, Inc., Washington.