1 00:00:02,000 --> 00:00:04,000 This is the ESOcast! 2 00:00:04,000 --> 00:00:08,000 Cutting-edge science and life behind the scenes of ESO, 3 00:00:08,000 --> 00:00:10,000 the European Southern Observatory, 4 00:00:11,000 --> 00:00:18,000 exploring the ultimate frontier with our host Dr J, a.k.a. Dr Joe Liske. 5 00:00:20,000 --> 00:00:23,000 Hello and welcome to this special episode of the ESOcast. 6 00:00:24,000 --> 00:00:27,500 Leading up to ESO’s 50th anniversary in October 2012 7 00:00:27,500 --> 00:00:30,000 we will showcase eight special features 8 00:00:30,000 --> 00:00:35,000 portraying ESO’s first 50 years of exploring the southern sky. 9 00:00:40,000 --> 00:00:44,000 Changing Views 10 00:00:51,000 --> 00:00:52,300 Great music, isn’t it? 11 00:00:53,440 --> 00:00:55,800 But suppose you had a hearing impairment. 12 00:00:55,800 --> 00:00:59,330 What if you couldn't hear the low frequencies? 13 00:01:00,660 --> 00:01:02,460 Or the high frequencies? 14 00:01:04,260 --> 00:01:06,950 Astronomers used to be in a similar situation. 15 00:01:07,650 --> 00:01:12,960 The human eye is only sensitive to a small part of all the radiation in the Universe. 16 00:01:12,960 --> 00:01:16,980 We can’t see light with wavelengths shorter than violet waves, 17 00:01:16,980 --> 00:01:19,040 or longer than red waves. 18 00:01:19,770 --> 00:01:22,890 We just don’t perceive the whole cosmic symphony. 19 00:01:25,000 --> 00:01:30,500 Infrared, or heat radiation, was first discovered by William Herschel, in 1800. 20 00:01:34,080 --> 00:01:37,130 In a dark room, you can’t see me. 21 00:01:38,000 --> 00:01:42,580 But put on infrared goggles, and you can “see” my body warmth. 22 00:01:45,690 --> 00:01:51,790 Likewise, infrared telescopes reveal cosmic objects too cool to give off visible light, 23 00:01:51,790 --> 00:01:56,380 like dark clouds of gas and dust where stars and planets are born. 24 00:02:05,500 --> 00:02:06,570 For decades, 25 00:02:06,570 --> 00:02:09,250 ESO astronomers have been keen to explore the Universe 26 00:02:09,250 --> 00:02:11,170 at infrared wavelengths. 27 00:02:11,910 --> 00:02:14,850 But the first detectors were small and hence inefficient. 28 00:02:15,490 --> 00:02:18,610 They gave us a blurry view of the infrared sky. 29 00:02:20,890 --> 00:02:24,530 Today’s infrared cameras are huge and powerful. 30 00:02:24,530 --> 00:02:29,410 They’re cooled to very low temperatures to increase their sensitivity. 31 00:02:31,000 --> 00:02:35,820 And ESO’s Very Large Telescope is designed to make good use of them. 32 00:02:40,710 --> 00:02:47,580 In fact, some technological tricks, like interferometry, only work in the infrared. 33 00:02:49,950 --> 00:02:54,190 We’ve broadened our view, to reveal the Universe in a new light. 34 00:02:57,860 --> 00:03:03,820 This dark blob is a cloud of cosmic dust. It blots out the stars in the background. 35 00:03:03,820 --> 00:03:08,530 But in the infrared, we can look straight through the dust. 36 00:03:10,560 --> 00:03:14,040 And here’s the Orion Nebula, a stellar nursery. 37 00:03:14,040 --> 00:03:18,470 Most of the newborn baby stars are hidden by dust clouds. 38 00:03:18,470 --> 00:03:24,720 Again, infrared comes to the rescue, revealing stars in the making! 39 00:03:35,920 --> 00:03:39,730 At the end of their lives, stars blow out bubbles of gas. 40 00:03:39,730 --> 00:03:43,450 Cosmic showpieces at optical wavelengths 41 00:03:43,450 --> 00:03:47,630 — but the infrared picture shows much more detail. 42 00:03:49,980 --> 00:03:52,320 Don’t forget the stars and gas clouds 43 00:03:52,320 --> 00:03:57,310 captured by the monstrous black hole in the core of our Milky Way galaxy. 44 00:03:57,310 --> 00:04:00,990 Without infrared cameras we would never see them. 45 00:04:03,170 --> 00:04:04,320 In other galaxies, 46 00:04:04,320 --> 00:04:09,460 infrared studies have revealed the true distribution of stars like our own Sun. 47 00:04:12,410 --> 00:04:16,089 The farthest galaxies can only be studied in the infrared. 48 00:04:16,089 --> 00:04:19,000 Their light has been shifted to these long wavelengths 49 00:04:19,269 --> 00:04:21,500 by the expansion of the Universe. 50 00:04:23,890 --> 00:04:28,230 Close to Paranal is a small mountain peak with an isolated building on top. 51 00:04:28,910 --> 00:04:32,500 Inside this building is the 4.1-metre VISTA telescope. 52 00:04:32,970 --> 00:04:36,520 It was built in the United Kingdom, ESO’s tenth Member State. 53 00:04:44,100 --> 00:04:47,230 For now, VISTA only does infrared. 54 00:04:47,230 --> 00:04:51,990 It uses a giant camera, weighing as much as a pickup truck. 55 00:04:52,460 --> 00:04:58,540 And yes, VISTA offers unprecedented vistas of the infrared Universe. 56 00:04:59,880 --> 00:05:03,700 ESO has been doing optical astronomy since its birth, fifty years ago. 57 00:05:06,840 --> 00:05:09,850 And infrared astronomy for about thirty years. 58 00:05:15,200 --> 00:05:18,040 But there are more registers to the cosmic symphony. 59 00:05:20,000 --> 00:05:24,200 Five thousand metres above sea level, high in the Chilean Andes, 60 00:05:24,200 --> 00:05:26,400 is the Chajnantor plateau. 61 00:05:27,920 --> 00:05:30,720 Astronomy doesn’t go higher than this. 62 00:05:34,020 --> 00:05:36,740 Chajnantor is home to ALMA 63 00:05:38,030 --> 00:05:41,240 – the Atacama Large Millimeter/submillimeter Array. 64 00:05:42,280 --> 00:05:44,160 ALMA is still under construction. 65 00:05:44,650 --> 00:05:48,020 At a site that is so hostile, it’s even hard to breathe! 66 00:05:51,210 --> 00:05:54,140 With just ten of the 66 antennas in place, 67 00:05:54,140 --> 00:05:58,660 ALMA made its first observations in the autumn of 2011. 68 00:06:03,080 --> 00:06:09,050 Millimetre waves from space. To observe them, you need to be high and dry. 69 00:06:09,050 --> 00:06:13,810 Chajnantor is one of the best places in the world for this. 70 00:06:18,580 --> 00:06:24,360 Clouds of cold gas and dark dust become visible in a pair of colliding galaxies. 71 00:06:24,870 --> 00:06:29,440 This is not where stars are born, but where they are conceived. 72 00:06:32,540 --> 00:06:36,170 And these spiral waves in the outflow of a dying star 73 00:06:36,170 --> 00:06:39,210 — could they be due to an orbiting planet? 74 00:06:43,750 --> 00:06:45,480 By changing the way we look, 75 00:06:45,480 --> 00:06:49,710 we’re closing in on the origins of planets, stars and galaxies. 76 00:06:50,310 --> 00:06:53,500 On the full symphony of the cosmos. 77 00:07:03,500 --> 00:07:07,600 This is Dr J, signing off from this special episode of the ESOcast. 78 00:07:07,600 --> 00:07:10,730 Join me again next time for another cosmic adventure. 79 00:07:13,460 --> 00:07:15,000 ESOcast is produced by ESO, 80 00:07:15,000 --> 00:07:16,500 the European Southern Observatory. 81 00:07:16,500 --> 00:07:18,940 ESO, the European Southern Observatory, 82 00:07:18,940 --> 00:07:21,000 is the pre-eminent intergovernmental science and technology organisation in astronomy, 83 00:07:21,000 --> 00:07:22,500 designing, constructing and operating the world’s most advanced ground-based telescopes. 84 00:07:25,970 --> 00:07:30,070 Transcription by ESO; translation by —