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Over the years, the Hubble 
Space Telescope has taken  

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hundreds of images of different kinds 
of incredible nebulae in our universe.

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A nebula is a giant cloud of dust and gas in 
space. There are different types of nebulae,  

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ranging from sites where stars are 
being born under gravitational pressures  

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to expanding gaseous remnants 
thrown off by dying stars.

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The famous Orion nebula is a star-forming region  

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only 1,500 light-years away, making it the 
closest large star-forming region to Earth.

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Because it is so bright and prominent, 
located just below Orion’s belt,  

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this nebula is one we can 
see with the unaided eye.  

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It also offers an excellent peek at 
stellar birth for those with telescopes.

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This nebula is an enormous cloud of dust and 
gas where vast numbers of new stars are forged.  

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Its bright, central region is the home of four 
massive, young stars that shape the nebula.  

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These four hefty stars are
called the Trapezium because they are arranged in  

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a trapezoidal pattern. Ultraviolet light unleashed 
by these stars is carving a cavity in the nebula  

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and disrupting the growth of 
hundreds of smaller stars.

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This stunning Hubble image offers the sharpest 
view of the Orion Nebula ever obtained.  

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Created using 520 different Hubble exposures taken 
in multiple wavelengths of light, this mosaic  

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contains over one billion pixels. The image’s 
orange color represents hydrogen, green is oxygen,  

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and red represents both sulfur and 
observations made in infrared light.

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While the Orion Nebula is in 
the midst of creating new stars,  

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other nebulae result from aging and dying stars.

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This image of the Cat’s Eye Nebula shows 
a bull's eye pattern of eleven or even  

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more concentric rings. Each 'ring' 
is actually the edge of a spherical  

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bubble seen projected onto the sky - that's 
why it appears bright along its outer edge.

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Observations suggest Cat’s Eye was 
created when a medium-sized star  

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ejected its mass in a series of pulses at 
1.500-year intervals. These convulsions  

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created dust shells that form a layered, 
concentric structure around the dying star.  

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The view from Hubble is like seeing an onion cut 
in half, where each skin layer appears as a ring.  

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Each shell contains as much mass as all of 
the planets in our solar system combined.

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Then, there are the supernova remnants,  

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like the Crab Nebula. These nebulae 
are made of debris from exploded stars.

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In the year 1054 AD, Chinese astronomers recorded a  

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“guest star” that was visible even in 
the daytime sky for nearly a month.  

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The “guest star” they observed was actually the 
supernova explosion that created the Crab Nebula.  

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Today the Crab Nebula is still visible as a 
six-light-year-wide remnant of that violent event.

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This large mosaic of the Crab Nebula was assembled 
from 24 individual exposures captured by Hubble  

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over three months. The orange filaments are the 
tattered remains of the star and consist mostly  

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of hydrogen. Green is sulfur, 
and red indicates doubly ionized oxygen.  

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These elements were expelled 
during the supernova explosion. 

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The leftover, ultra-dense core of the exploded 
star remains as a rapidly spinning neutron star  

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in the center of the Crab Nebula. Electrons 
whirling at nearly the speed of light around  

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the star’s magnetic field lines produce the 
eerie blue light in the interior of the nebula.  

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The neutron star, like a lighthouse, 
ejects twin beams of radiation  

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that make it appear to 
pulse 30 times per second as it rotates. 

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Nebulae are some of the most beautiful objects in 
our universe. Their incredible shapes and colors  

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will always inspire humanity to keep looking up at 
the stars. And with instruments like the Hubble  

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Space Telescope, we will continue to be able 
to uncover the many mysteries of the universe.

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