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1 00:00:01,001 --> 00:00:03,269 [Music throughout] My name is Judy Racusin. 2 00:00:03,269 --> 00:00:06,639 I'm the deputy project scientist on the Fermi Gamma-ray Space Telescope. 3 00:00:07,507 --> 00:00:11,011 I'm here today to watch a video with you of observations 4 00:00:11,011 --> 00:00:14,681 collected by the Fermi Large Area Telescope, or the LAT. 5 00:00:14,748 --> 00:00:17,917 It surveys the entire sky every few hours. 6 00:00:17,917 --> 00:00:20,453 This allows it to do a lot of really cool things. 7 00:00:20,453 --> 00:00:23,156 It can look at sources that vary on timescales 8 00:00:23,156 --> 00:00:26,092 from a fraction of a second to years on end. 9 00:00:26,092 --> 00:00:28,695 There's a thin band across the middle of the image, 10 00:00:28,695 --> 00:00:30,163 and that's the Milky Way. 11 00:00:30,296 --> 00:00:32,632 The color scheme, blue, red, yellow. 12 00:00:32,632 --> 00:00:36,903 This is just a way for us to visualize it because our eyes don't see gamma rays. 13 00:00:37,103 --> 00:00:40,974 Fermi isn't an imaging instrument like you think of Hubble or Webb. 14 00:00:40,974 --> 00:00:43,576 What it is is it's actually a photon collecting instrument. 15 00:00:43,576 --> 00:00:45,712 It's a particle detector in space. 16 00:00:45,712 --> 00:00:49,716 And we make these maps by adding up all of the photons we collect. 17 00:00:50,383 --> 00:00:53,019 Those circular sources that you see in the galactic plane 18 00:00:53,019 --> 00:00:54,721 are actually individual objects. 19 00:00:54,721 --> 00:00:56,423 Most of those are pulsars. 20 00:00:56,956 --> 00:00:59,259 We see sources above and below 21 00:00:59,259 --> 00:01:02,629 the galactic plane. Those are largely blazars. 22 00:01:02,829 --> 00:01:07,233 What that is, is a supermassive black hole, millions to billions of times 23 00:01:07,233 --> 00:01:10,904 the mass of our Sun, the center of a galaxy that is active. 24 00:01:11,171 --> 00:01:15,041 That means that there's gas and stars falling into it, 25 00:01:15,108 --> 00:01:20,046 and it produces jets of emission And they're very chaotic systems. 26 00:01:20,680 --> 00:01:21,481 This video 27 00:01:21,481 --> 00:01:25,752 showing the first 14 years of Fermi observations is just the beginning. 28 00:01:25,852 --> 00:01:28,888 Fermi continues to observe the dynamic sky every day, 29 00:01:28,888 --> 00:01:31,724 and we hope it'll continue to do so for many years into the future. 30 00:01:32,525 --> 00:01:37,564 NASA |