Orion Nebula M42 Hubble pictures:
Other HST pictures of M42:
Crucible of Creation
Panoramic Hubble mosaic zooms in
on Maelstrom of star birth
This color panorama of the center the Orion nebula is one
of the largest pictures ever assembled from individual images taken
with NASA’s Hubble Space Telescope. Seamlessly composited
from a mosaic of 15 separate fields, it covers an area about
five percent that covered by the full Moon.
The seemingly infinite tapestry of rich detail revealed by Hubble shows
a churning turbulent star factory set within a maelstrom of flowing,
luminescent gas. Though this 2.5 light-years wide view is still a
small portion of the entire nebula, it includes almost all of the light
from the bright glowing clouds of gas and a star cluster associated
with the nebula. Hubble reveals details as small as 4.1 billion miles
across (less than the distance of Neptune from the Sun).
Hubble Space Telescope 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 and solar system 4.5 billion
years ago. Many of the nebula’s details can’t be captured in a single
picture – any more than one snapshot of the Grand Canyon yields clues
to its formation and history. Like the Grand Canyon, the Orion nebula
has a dramatic surface topography — of glowing gasses instead of rock
— with peaks, valleys and walls. They are illuminated and heated by
a torrent of energetic ultraviolet light from its four hottest and most
massive stars, called the Trapezium, which lie near the center of the
image.
In addition to the Trapezium, this stellar cavern contains 700 hundred
other young stars at various stages of formation. High-speed jets of
hot gas spewed by some of the infant stars send supersonic shock waves
tearing into the nebula at 100,000 miles per hour. These shock waves
appear as thin curved loops, sometimes with bright knots on their end
(the brightest examples are near the bright star at the lower left).
The mosaic reveals at least 153 glowing protoplanetary disks (first
discovered with the Hubble in 1992, and dubbed “proplyds”) that are
believed to be embryonic solar systems that will eventually form
planets. (Our solar system has long been considered the relic of just
such a disk that formed around the newborn Sun). The abundance of such
objects in the Orion nebula strengthens the argument that planet
formation is a common occurrence in the universe. The proplyds that
are closest to the Trapezium stars (image center) are shedding some of
their gas and dust. The pressure of starlight from the hottest stars
forms “tails” which act like wind vanes pointing away from the
Trapezium. These tails result from the light from the star pushing the
dust and gas away from the outside layers of the proplyds. In addition
to the luminescent proplyds, seven disks are silhouetted against the
bright background of the nebula. These dark objects allow Hubble
astronomers to estimate the masses of the disks as at least 0.1 to 730
times the mass of our Earth.
Located 1,500 light-years away, along our spiral arm of the Milky Way,
the Orion nebula is located in the middle of the sword region of the
constellation Orion the Hunter, which dominates the early winter
evening sky, at northern latitudes. The stars have formed from
collapsing clouds of interstellar gas within the last million years.
The most massive clouds have formed the brightest stars near the center
and these are so hot that they illuminate the gas left behind after the
period of star formation was complete. The more numerous faint stars
are still in the process of collapsing under their own gravity, but
have become hot enough in their centers to be self luminous bodies.
Technical information: To create this color mosaic, 45 separate images
of the Orion nebula were taken in blue, green and red between January
1994 and March 1995. Light emitted by oxygen is shown as blue,
hydrogen emission is shown as green, and nitrogen emission as red
light. The overall color balance is close to that which an observer
living near the Orion nebula would see. The irregular borders produced
by the HST images have been smoothed out by the addition of images from
the European Southern Observatory in Chile obtained by Bo Reipurth and
John Bally, these being about 2% of the area shown here and lying at
the top left corner.
Credit: C.R. O’Dell (Rice University), and NASA
- Original press release
Planetary Systems in the Making
These are HST images of four newly discovered
protoplanetary disks around young stars in the Orion nebula, located
1,500 light-years away. Gas and dust disks, long suspected by
astronomers to be an early stage of planetary formation, can be
directly seen in visible light by Hubble.
Disks around young stars (also known as circumstellar or protoplanetary
disks) are thought to be made up of 99% gas and 1% dust. Even that
small amount of dust is enough to make the disks opaque and dark at
visible wavelengths. The dark disks are seen in these images because
they are silhouetted against the bright backdrop of the hot gas of the
Orion nebula.
The red glow in the center of each disk is a young, newly formed star,
roughly one million years old (compared to the 4.5 billion year age of
the Sun). The stars range in mass from 30% to 150% of the mass of our
own Sun. As they evolve, the disks may go on to form planetary systems
like our own. While only a handful of these dark silhouette disks have
been discovered so far, they seem to belong to a much larger family of
similar objects, and current indications are that protoplanetary disks
are common in the Orion nebula.
Mark McCaughrean of the Max-Planck-Institute for Astronomy, Heidelberg,
Germany, and his collaborator C. Robert O’Dell from Rice University,
Houston, Texas, spotted the new disks in large-scale survey images of
the Orion nebula that O’Dell had taken with Hubble between January 1994
and March 1995. A detailed study of the disk images has been submitted
for publication to the Astronomical Journal.
Each image is 167 billion miles, or 257 billion kilometers across (30
times the diameter of our own solar system). The disks range in size
from two to eight times the diameter of our solar system. The
researchers explain the different circular or elliptical shapes as
being due to the fact that each disk is tilted toward Earth by
different degrees.
Each picture is a composite of three images taken with Hubble’s Wide
Field and Planetary Camera 2, through narrow-band filters which admit
the light of emission lines of ionized oxygen (represented here by
blue), hydrogen (green), and nitrogen (red). The hot gas of the
background Orion nebula emits strongly at each of these wavelengths,
providing a strong backdrop for the disks to be silhouetted against.
In each case, the central star is also clearly visible.
Credit: Mark McCaughrean (Max-Planck-Institute for Astronomy),
C. Robert O’Dell (Rice University), and NASA
- Original Press Release
Edge-on protoplanetary disk in the Orion nebula
Resembling an interstellar Frisbee, this is a disk of dust seen edge-on
around a newborn star in the Orion nebula, located 1,500 light-years
away. Because the disk is edge-on, the star is largely hidden inside,
in this striking Hubble Space Telescope picture. The disk may be an
embryonic planetary system in the making. Our solar system probably
formed out of just such a disk 4.5 billion years ago. At 17 times the
diameter of our own solar system, this disk is the largest of several
recently discovered in the Orion nebula.
The left image is a three-color composite, taken in blue, green, and
red emission lines from glowing gas in the nebula. The right image was
taken through a different filter, which blocks any bright spectral
emission lines from the nebula, and hence the disk itself is less
distinctly silhouetted against the background. However, clearly
visible in this image are nebulosities above and below the plane of the
disk; these betray the presence of the otherwise invisible central
star, which cannot be seen directly due to dust in the edge-on disk.
The images were taken between January 1994 and March 1995, and a study
of their characteristics has been submitted for publication to the
Astronomical Journal.
Credit: Mark McCaughrean (Max-Planck-Institute for Astronomy),
C. Robert O’Dell (Rice University), and NASA
- Original Press Release
Last Modification: 24 May 1998, 15:55 MET