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Over the years, the Hubble Space Telescope has taken
hundreds of images of different kinds of incredible nebulae in our universe.
A nebula is a giant cloud of dust and gas in space. There are different types of nebulae,
ranging from sites where stars are being born under gravitational pressures
to expanding gaseous remnants thrown off by dying stars.
The famous Orion nebula is a star-forming region
only 1,500 light-years away, making it the closest large star-forming region to Earth.
Because it is so bright and prominent, located just below Orion’s belt,
this nebula is one we can see with the unaided eye.
It also offers an excellent peek at stellar birth for those with telescopes.
This nebula is an enormous cloud of dust and gas where vast numbers of new stars are forged.
Its bright, central region is the home of four massive, young stars that shape the nebula.
These four hefty stars are called the Trapezium because they are arranged in
a trapezoidal pattern. Ultraviolet light unleashed by these stars is carving a cavity in the nebula
and disrupting the growth of hundreds of smaller stars.
This stunning Hubble image offers the sharpest view of the Orion Nebula ever obtained.
Created using 520 different Hubble exposures taken in multiple wavelengths of light, this mosaic
contains over one billion pixels. The image’s orange color represents hydrogen, green is oxygen,
and red represents both sulfur and observations made in infrared light.
While the Orion Nebula is in the midst of creating new stars,
other nebulae result from aging and dying stars.
This image of the Cat’s Eye Nebula shows a bull's eye pattern of eleven or even
more concentric rings. Each 'ring' is actually the edge of a spherical
bubble seen projected onto the sky - that's why it appears bright along its outer edge.
Observations suggest Cat’s Eye was created when a medium-sized star
ejected its mass in a series of pulses at 1,500-year intervals. These convulsions
created dust shells that form a layered, concentric structure around the dying star.
The view from Hubble is like seeing an onion cut in half, where each skin layer appears as a ring.
Each shell contains as much mass as all of the planets in our solar system combined.
Then, there are the supernova remnants,
like the Crab Nebula. These nebulae are made of debris from exploded stars.
In the year 1054 AD, Chinese astronomers recorded a
“guest star” that was visible even in the daytime sky for nearly a month.
The “guest star” they observed was actually the supernova explosion that created the Crab Nebula.
Today the Crab Nebula is still visible as a six-light-year-wide remnant of that violent event.
This large mosaic of the Crab Nebula was assembled from 24 individual exposures captured by Hubble
over three months. The orange filaments are the tattered remains of the star and consist mostly
of hydrogen. Green is sulfur, and red indicates doubly ionized oxygen.
These elements were expelled during the supernova explosion.
The leftover, ultra-dense core of the exploded star remains as a rapidly spinning neutron star
in the center of the Crab Nebula. Electrons whirling at nearly the speed of light around
the star’s magnetic field lines produce the eerie blue light in the interior of the nebula.
The neutron star, like a lighthouse, ejects twin beams of radiation
that make it appear to pulse 30 times per second as it rotates.
Nebulae are some of the most beautiful objects in our universe. Their incredible shapes and colors
will always inspire humanity to keep looking up at the stars. And with instruments like the Hubble
Space Telescope, we will continue to be able to uncover the many mysteries of the universe.
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