1 00:00:00,000 --> 00:00:02,720 [ MUSIC ] 2 00:00:02,720 --> 00:00:05,920 Over the years, the Hubble  Space Telescope has taken   3 00:00:05,920 --> 00:00:11,600 hundreds of images of different kinds  of incredible nebulae in our universe. 4 00:00:11,600 --> 00:00:18,480 A nebula is a giant cloud of dust and gas in  space. There are different types of nebulae,   5 00:00:18,480 --> 00:00:23,440 ranging from sites where stars are  being born under gravitational pressures   6 00:00:23,440 --> 00:00:28,320 to expanding gaseous remnants  thrown off by dying stars. 7 00:00:28,320 --> 00:00:31,840 The famous Orion nebula is a star-forming region   8 00:00:31,840 --> 00:00:39,360 only 1,500 light-years away, making it the  closest large star-forming region to Earth. 9 00:00:39,360 --> 00:00:44,160 Because it is so bright and prominent,  located just below Orion’s belt,   10 00:00:44,160 --> 00:00:48,160 this nebula is one we can  see with the unaided eye.   11 00:00:48,160 --> 00:00:53,600 It also offers an excellent peek at  stellar birth for those with telescopes. 12 00:00:53,600 --> 00:01:00,960 This nebula is an enormous cloud of dust and  gas where vast numbers of new stars are forged.   13 00:01:00,960 --> 00:01:07,760 Its bright, central region is the home of four  massive, young stars that shape the nebula.   14 00:01:07,760 --> 00:01:12,480 These four hefty stars are called the Trapezium because they are arranged in   15 00:01:12,480 --> 00:01:20,640 a trapezoidal pattern. Ultraviolet light unleashed  by these stars is carving a cavity in the nebula   16 00:01:20,640 --> 00:01:25,040 and disrupting the growth of  hundreds of smaller stars. 17 00:01:25,040 --> 00:01:31,280 This stunning Hubble image offers the sharpest  view of the Orion Nebula ever obtained.   18 00:01:31,280 --> 00:01:39,040 Created using 520 different Hubble exposures taken  in multiple wavelengths of light, this mosaic   19 00:01:39,040 --> 00:01:48,000 contains over one billion pixels. The image’s  orange color represents hydrogen, green is oxygen,   20 00:01:48,000 --> 00:01:54,240 and red represents both sulfur and  observations made in infrared light. 21 00:01:54,240 --> 00:01:58,320 While the Orion Nebula is in  the midst of creating new stars,   22 00:01:58,320 --> 00:02:03,520 other nebulae result from aging and dying stars. 23 00:02:03,520 --> 00:02:08,720 This image of the Cat’s Eye Nebula shows  a bull's eye pattern of eleven or even   24 00:02:08,720 --> 00:02:14,240 more concentric rings. Each 'ring'  is actually the edge of a spherical   25 00:02:14,240 --> 00:02:20,960 bubble seen projected onto the sky - that's  why it appears bright along its outer edge. 26 00:02:20,960 --> 00:02:25,840 Observations suggest Cat’s Eye was  created when a medium-sized star   27 00:02:25,840 --> 00:02:33,040 ejected its mass in a series of pulses at  1,500-year intervals. These convulsions   28 00:02:33,040 --> 00:02:40,080 created dust shells that form a layered,  concentric structure around the dying star.   29 00:02:40,080 --> 00:02:47,440 The view from Hubble is like seeing an onion cut  in half, where each skin layer appears as a ring.   30 00:02:47,440 --> 00:02:54,960 Each shell contains as much mass as all of  the planets in our solar system combined. 31 00:02:54,960 --> 00:02:57,440 Then, there are the supernova remnants,   32 00:02:57,440 --> 00:03:04,640 like the Crab Nebula. These nebulae  are made of debris from exploded stars. 33 00:03:04,640 --> 00:03:09,840 In the year 1054 AD, Chinese astronomers recorded a   34 00:03:09,840 --> 00:03:16,080 “guest star” that was visible even in  the daytime sky for nearly a month.   35 00:03:16,080 --> 00:03:23,600 The “guest star” they observed was actually the  supernova explosion that created the Crab Nebula.   36 00:03:23,600 --> 00:03:32,000 Today the Crab Nebula is still visible as a  six-light-year-wide remnant of that violent event. 37 00:03:32,000 --> 00:03:38,960 This large mosaic of the Crab Nebula was assembled  from 24 individual exposures captured by Hubble   38 00:03:38,960 --> 00:03:45,680 over three months. The orange filaments are the  tattered remains of the star and consist mostly   39 00:03:45,680 --> 00:03:52,720 of hydrogen. Green is sulfur,  and red indicates doubly ionized oxygen.   40 00:03:52,720 --> 00:03:57,920 These elements were expelled  during the supernova explosion.  41 00:03:57,920 --> 00:04:05,360 The leftover, ultra-dense core of the exploded  star remains as a rapidly spinning neutron star   42 00:04:05,360 --> 00:04:11,840 in the center of the Crab Nebula. Electrons  whirling at nearly the speed of light around   43 00:04:11,840 --> 00:04:19,440 the star’s magnetic field lines produce the  eerie blue light in the interior of the nebula.   44 00:04:19,440 --> 00:04:24,960 The neutron star, like a lighthouse,  ejects twin beams of radiation   45 00:04:24,960 --> 00:04:31,520 that make it appear to  pulse 30 times per second as it rotates.  46 00:04:31,520 --> 00:04:38,560 Nebulae are some of the most beautiful objects in  our universe. Their incredible shapes and colors   47 00:04:38,560 --> 00:04:45,200 will always inspire humanity to keep looking up at  the stars. And with instruments like the Hubble   48 00:04:45,200 --> 00:04:53,068 Space Telescope, we will continue to be able  to uncover the many mysteries of the universe. 49 00:04:53,068 --> 00:04:59,132 [ MUSIC ]