1 00:00:02,520 --> 00:00:06,520 Changing Views 2 00:00:13,520 --> 00:00:14,820 Great music, isn’t it? 3 00:00:15,960 --> 00:00:18,320 But suppose you had a hearing impairment. 4 00:00:18,320 --> 00:00:21,850 What if you couldn't hear the low frequencies? 5 00:00:23,180 --> 00:00:24,980 Or the high frequencies? 6 00:00:26,780 --> 00:00:29,470 Astronomers used to be in a similar situation. 7 00:00:30,170 --> 00:00:35,480 The human eye is only sensitive to a small part of all the radiation in the Universe. 8 00:00:35,480 --> 00:00:39,500 We can’t see light with wavelengths shorter than violet waves, 9 00:00:39,500 --> 00:00:41,560 or longer than red waves. 10 00:00:42,290 --> 00:00:45,410 We just don’t perceive the whole cosmic symphony. 11 00:00:47,520 --> 00:00:53,020 Infrared, or heat radiation, was first discovered by William Herschel, in 1800. 12 00:00:56,600 --> 00:00:59,650 In a dark room, you can’t see me. 13 00:01:00,520 --> 00:01:05,100 But put on infrared goggles, and you can “see” my body warmth. 14 00:01:08,210 --> 00:01:14,310 Likewise, infrared telescopes reveal cosmic objects too cool to give off visible light, 15 00:01:14,310 --> 00:01:18,900 like dark clouds of gas and dust where stars and planets are born. 16 00:01:28,020 --> 00:01:29,090 For decades, 17 00:01:29,090 --> 00:01:31,770 ESO astronomers have been keen to explore the Universe 18 00:01:31,770 --> 00:01:33,690 at infrared wavelengths. 19 00:01:34,430 --> 00:01:37,370 But the first detectors were small and hence inefficient. 20 00:01:38,010 --> 00:01:41,130 They gave us a blurry view of the infrared sky. 21 00:01:43,410 --> 00:01:47,050 Today’s infrared cameras are huge and powerful. 22 00:01:47,050 --> 00:01:51,930 They’re cooled to very low temperatures to increase their sensitivity. 23 00:01:53,520 --> 00:01:58,340 And ESO’s Very Large Telescope is designed to make good use of them. 24 00:02:03,230 --> 00:02:10,100 In fact, some technological tricks, like interferometry, only work in the infrared. 25 00:02:12,470 --> 00:02:16,710 We’ve broadened our view, to reveal the Universe in a new light. 26 00:02:20,380 --> 00:02:26,340 This dark blob is a cloud of cosmic dust. It blots out the stars in the background. 27 00:02:26,340 --> 00:02:31,050 But in the infrared, we can look straight through the dust. 28 00:02:33,080 --> 00:02:36,560 And here’s the Orion Nebula, a stellar nursery. 29 00:02:36,560 --> 00:02:40,990 Most of the newborn baby stars are hidden by dust clouds. 30 00:02:40,990 --> 00:02:47,240 Again, infrared comes to the rescue, revealing stars in the making! 31 00:02:58,440 --> 00:03:02,250 At the end of their lives, stars blow out bubbles of gas. 32 00:03:02,250 --> 00:03:05,970 Cosmic showpieces at optical wavelengths 33 00:03:05,970 --> 00:03:10,150 — but the infrared picture shows much more detail. 34 00:03:12,500 --> 00:03:14,840 Don’t forget the stars and gas clouds 35 00:03:14,840 --> 00:03:19,830 captured by the monstrous black hole in the core of our Milky Way galaxy. 36 00:03:19,830 --> 00:03:23,510 Without infrared cameras we would never see them. 37 00:03:25,690 --> 00:03:26,840 In other galaxies, 38 00:03:26,840 --> 00:03:31,980 infrared studies have revealed the true distribution of stars like our own Sun. 39 00:03:34,930 --> 00:03:38,609 The farthest galaxies can only be studied in the infrared. 40 00:03:38,609 --> 00:03:41,520 Their light has been shifted to these long wavelengths 41 00:03:41,789 --> 00:03:44,020 by the expansion of the Universe. 42 00:03:46,410 --> 00:03:50,750 Close to Paranal is a small mountain peak with an isolated building on top. 43 00:03:51,430 --> 00:03:55,020 Inside this building is the 4.1-metre VISTA telescope. 44 00:03:55,490 --> 00:03:59,040 It was built in the United Kingdom, ESO’s tenth Member State. 45 00:04:06,620 --> 00:04:09,750 For now, VISTA only does infrared. 46 00:04:09,750 --> 00:04:14,510 It uses a giant camera, weighing as much as a pickup truck. 47 00:04:14,980 --> 00:04:21,060 And yes, VISTA offers unprecedented vistas of the infrared Universe. 48 00:04:22,400 --> 00:04:26,220 ESO has been doing optical astronomy since its birth, fifty years ago. 49 00:04:29,360 --> 00:04:32,370 And infrared astronomy for about thirty years. 50 00:04:37,720 --> 00:04:40,560 But there are more registers to the cosmic symphony. 51 00:04:42,520 --> 00:04:46,720 Five thousand metres above sea level, high in the Chilean Andes, 52 00:04:46,720 --> 00:04:48,920 is the Chajnantor plateau. 53 00:04:50,440 --> 00:04:53,240 Astronomy doesn’t go higher than this. 54 00:04:56,540 --> 00:04:59,260 Chajnantor is home to ALMA 55 00:05:00,550 --> 00:05:03,760 – the Atacama Large Millimeter/submillimeter Array. 56 00:05:04,800 --> 00:05:06,680 ALMA is still under construction. 57 00:05:07,170 --> 00:05:10,540 At a site that is so hostile, it’s even hard to breathe! 58 00:05:13,730 --> 00:05:16,660 With just ten of the 66 antennas in place, 59 00:05:16,660 --> 00:05:21,180 ALMA made its first observations in the autumn of 2011. 60 00:05:25,600 --> 00:05:31,570 Millimetre waves from space. To observe them, you need to be high and dry. 61 00:05:31,570 --> 00:05:36,330 Chajnantor is one of the best places in the world for this. 62 00:05:41,100 --> 00:05:46,880 Clouds of cold gas and dark dust become visible in a pair of colliding galaxies. 63 00:05:47,390 --> 00:05:51,960 This is not where stars are born, but where they are conceived. 64 00:05:55,060 --> 00:05:58,690 And these spiral waves in the outflow of a dying star 65 00:05:58,690 --> 00:06:01,730 — could they be due to an orbiting planet? 66 00:06:06,270 --> 00:06:08,000 By changing the way we look, 67 00:06:08,000 --> 00:06:12,230 we’re closing in on the origins of planets, stars and galaxies. 68 00:06:12,830 --> 00:06:16,020 On the full symphony of the cosmos.