| ABOUT
THIS IMAGE:
NASA's Hubble Space Telescope has snapped a panoramic portrait of a vast,
sculpted landscape of gas and dust where thousands of stars are being
born. This fertile star-forming region, called the 30 Doradus Nebula,
has a sparkling stellar centerpiece: the most spectacular cluster of massive
stars in our cosmic neighborhood of about 25 galaxies.
The mosaic picture shows that ultraviolet radiation and high-speed material
unleashed by the stars in the cluster, called R136 [the large blue blob
left of center], are weaving a tapestry of creation and destruction, triggering
the collapse of looming gas and dust clouds and forming pillar-like structures
that are incubators for nascent stars.
The photo offers an unprecedented, detailed view of the entire inner region
of 30 Doradus, measuring 200 light-years wide by 150 light-years high.
The nebula resides in the Large Magellanic Cloud (a satellite galaxy of
the Milky Way), 170,000 light-years from Earth.
Nebulas like 30 Doradus are the "signposts" of recent star birth.
High-energy ultraviolet radiation from the young, hot, massive stars in
R136 causes the surrounding gaseous material to glow. Previous Hubble
telescope observations showed that R136 contains several dozen of the
most massive stars known, each about 100 times the mass of the Sun and
about 10 times as hot. These stellar behemoths all formed at the same
time about 2 million years ago.
The stars in R136 are producing intense "stellar winds" (streams
of material traveling at several million miles an hour), which are wreaking
havoc on the gas and dust in the surrounding neighborhood. The winds are
pushing the gas away from the cluster and compressing the inner regions
of the surrounding gas and dust clouds [the pinkish material]. The intense
pressure is triggering the collapse of parts of the clouds, producing
a new generation of star formation around the central cluster. The new
stellar nursery is about 30 to 50 light-years from R136. Most of the stars
in the nursery are not visible because they are still encased in their
cocoons of gas and dust.
Some of the nascent stars are forming in long columns of gas and dust.
Previous Hubble observations revealed that the process of "triggered"
star formation often involves massive pillars of material that point toward
the central cluster. Such pillars form when particularly dense clouds
of gas and dust shield columns of material behind them from the blistering
radiation and strong winds released by massive stars, like the stars in
R136. This protected material becomes the pillars where stars can form
and grow. The Hubble telescope first spied these pillars of stellar creation
when it captured close-up views of the Eagle Nebula.
The new image of 30 Doradus shows numerous pillars each several
light-years long oriented toward the central cluster. These pillars,
which resemble tiny fingers, are similar in size to those in the Eagle
Nebula. Without Hubble's resolution, they would not be visible. One pillar
is visible within the oval-shaped structure to the left of the cluster.
Two [one dark and one bright] are next to each other below and to the
right of the cluster. One pillar is at upper right, and still another
is just above the cluster.
Newborn stars within most of these pillars already have been discovered
in pictures taken by Hubble's infrared camera, the Near Infrared Camera
and Multi-Object Spectrometer, which can penetrate the dust to detect
embryonic stars. Eventually, intense radiation and stellar winds from
the developing stars will blow off the tops of the pillars. The Hubble
image shows that one such eruption already has occurred in 30 Doradus.
A trio of young stars has just been "born" by breaking out of
its natal pillar. These new stars are just a few hundred thousand years
old.
In another 2 million years, the new generation of stars will be in full
bloom. But the massive stars in R136 will have burned themselves out.
And the nebula's central region will be a giant shell, devoid of gas and
dust. Still later, all of the most massive stars and gas will have disappeared
from the entire region. Only older, less massive stars will remain in
a region cleared of gas and dust.
The mosaic image of 30 Doradus consists of five overlapping pictures taken
between January 1994 and September 2000 by Hubble's Wide Field and Planetary
Camera 2. Several color filters were used to enhance important details
in the stars and the nebula. Blue corresponds to the hot stars. The greenish
color denotes hot gas energized by the central cluster of stars. Pink
depicts the glowing edges of the gas and dust clouds facing the cluster,
which are being bombarded by winds and radiation. Reddish-brown represents
the cooler surfaces of the clouds, which are not receiving direct radiation
from the central cluster.
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