WEBVTT FILE 1 00:00:07.215 --> 00:00:08.133 This is an image of 2 00:00:08.133 --> 00:00:12.971 something called the Antennae galaxies discovered by William Herschel. 3 00:00:13.763 --> 00:00:18.101 About 45 million light years away from our Milky Way. 4 00:00:18.184 --> 00:00:23.106 These are actually two galaxies that are in the process of merging. 5 00:00:23.106 --> 00:00:26.776 They will end up eventually as one bigger galaxy, 6 00:00:27.444 --> 00:00:30.488 We have the privilege of catching it with this brilliant Hubble 7 00:00:30.488 --> 00:00:35.118 Space Telescope image during the process of merging. 8 00:00:35.118 --> 00:00:38.705 So what you can see here is a lot of activity. 9 00:00:38.747 --> 00:00:40.749 First of all, you see a lot of light. 10 00:00:40.749 --> 00:00:43.918 This is from starlight blended together 11 00:00:43.918 --> 00:00:47.047 and you can see at the core of one galaxy 12 00:00:47.047 --> 00:00:50.050 and the other down here with a lot of blended starlight. 13 00:00:50.091 --> 00:00:52.761 But you also see disrupted structure. 14 00:00:52.761 --> 00:00:57.891 You know, a few hundred million years ago these were two separate spiral galaxies. 15 00:00:57.891 --> 00:01:02.604 Now they are in the process of merging and that spiral structure 16 00:01:02.604 --> 00:01:08.276 has been disrupted by the gravitational pulls between the two galaxies. 17 00:01:08.276 --> 00:01:13.406 And not only that, but that disruption has stirred up a lot of the gas 18 00:01:13.406 --> 00:01:17.285 and the dust that were within each of the independent galaxies. 19 00:01:17.285 --> 00:01:22.248 And that stirring up actually compresses some of the gas and incites 20 00:01:22.248 --> 00:01:26.252 new star formation at a very vigorous pace. 21 00:01:26.503 --> 00:01:30.256 So the bright purple light here that we see all around 22 00:01:30.256 --> 00:01:33.426 this pair of merging galaxies are nebulae 23 00:01:33.426 --> 00:01:37.388 that are really very energetically forming stars. 24 00:01:38.807 --> 00:01:42.018 Their light is ionizing the surrounding gas. 25 00:01:42.018 --> 00:01:44.270 It's creating these beautiful colors. 26 00:01:44.521 --> 00:01:47.023 You can also see lots and lots of dust 27 00:01:47.023 --> 00:01:50.068 in these regions as the galaxies merge. 28 00:01:51.194 --> 00:01:56.241 So we call this a star burst because it's a burst of star formation 29 00:01:56.241 --> 00:02:01.746 that's being incited and excited by the merging process of these two 30 00:02:01.746 --> 00:02:04.040 originally independent galaxies. 31 00:02:05.625 --> 00:02:11.506 There’s so much material in this starburst process that's being compressed that it enables 32 00:02:11.506 --> 00:02:16.553 not just individual isolated stars to form, but whole clusters of stars to form. 33 00:02:16.886 --> 00:02:19.722 And that creates a lot of energetic radiation 34 00:02:19.722 --> 00:02:23.643 that can then light up the surrounding gas that's left over 35 00:02:23.643 --> 00:02:28.064 and just makes for a brilliant picture of vibrant star formation. 36 00:02:29.440 --> 00:02:31.860 So catching this in the act with Hubble, 37 00:02:31.860 --> 00:02:35.155 I think is is a wonderful gift and achievement. 38 00:02:35.155 --> 00:02:37.740 And I love looking at this picture for that reason.