1 00:00:00,000 --> 00:00:07,052 "Hubble Science" 2 00:00:07,053 --> 00:00:14,560 "Black Holes // From Myth to Reality" 3 00:00:14,560 --> 00:00:20,560 One of the Hubble space telescope's  major achievements was the confirmation   4 00:00:20,560 --> 00:00:31,567 that galaxies have in their  core supermassive black holes. 5 00:00:31,567 --> 00:00:39,040 At least for a time were kind of a mythical idea, you know, a mathematical possibility coming from   6 00:00:39,040 --> 00:00:45,200 the physics, but it was not clear decades ago  whether we could actually observe a black hole   7 00:00:45,200 --> 00:00:50,640 because kind of by definition black holes  are not viewable, the light cannot escape. 8 00:00:50,640 --> 00:00:56,686 So the question is, could you observe effects of  black holes to determine that they are there? 9 00:00:56,686 --> 00:01:03,280 Now the way Hubble has detected this is  by looking not at the black hole which   10 00:01:03,280 --> 00:01:07,520 is really impossible to see, what we see  is material right around the black hole   11 00:01:07,520 --> 00:01:15,180 particularly this galaxy called M87 which has  a spectacular ejected jet which you can see. 12 00:01:15,180 --> 00:01:23,760 And often we see material orbiting that inner  black hole, like gas, and orbiting very fast so   13 00:01:23,760 --> 00:01:28,000 we can use the instruments on Hubble to  discern whether material on one side of   14 00:01:28,000 --> 00:01:32,000 the black hole is moving away from us and the  material on the other side is moving toward us   15 00:01:32,000 --> 00:01:44,560 as you might expect if the material is orbiting. Since that time Hubble has followed up with many   16 00:01:44,560 --> 00:01:50,240 other galaxies and seen evidence for supermassive  black holes so we now believe that most   17 00:01:50,240 --> 00:01:54,640 and maybe all galaxies have some kind  of supermassive black hole in the center. 18 00:01:54,640 --> 00:02:01,920 [ INTENSE MUSIC ] 19 00:02:01,920 --> 00:02:05,680 People did not dream that that would be true. It wasn't that long ago that people thought   20 00:02:05,680 --> 00:02:10,480 there were no black holes, then we thought well  we don't imagine how they could exist so there   21 00:02:10,480 --> 00:02:21,840 probably aren't any. And now we are forced into  understanding how come there are so many of them. 22 00:02:21,840 --> 00:02:37,907 [ INTENSE MUSIC ]