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1 00:00:00,000 --> 00:00:00,734 [Music throughout] 2 00:00:00,734 --> 00:00:03,269 From its perch on the International Space Station, 3 00:00:03,269 --> 00:00:06,406 NASA's NICER X-ray telescope has helped map 4 00:00:06,406 --> 00:00:09,542 a mysterious cosmic event for the first time. 5 00:00:10,176 --> 00:00:13,380 It happened in a galaxy 300 million light-years away. 6 00:00:13,747 --> 00:00:16,383 Astronomers call this system Ansky. 7 00:00:17,250 --> 00:00:20,387 Ansky produces a type of recurring X-ray outburst 8 00:00:20,387 --> 00:00:23,723 called a QPE, or quasi-periodic eruption. 9 00:00:23,890 --> 00:00:26,459 These events were just recently discovered. 10 00:00:26,760 --> 00:00:32,098 Ansky is only the eighth known QPE emitter and is the most energetic to date. 11 00:00:32,532 --> 00:00:36,336 Some scientists think QPEs occur when a lower-mass object 12 00:00:36,336 --> 00:00:39,873 orbits a supermassive black hole in the center of a galaxy. 13 00:00:40,774 --> 00:00:44,044 When the smaller object passes through the disk of gas around the 14 00:00:44,044 --> 00:00:47,047 monster black hole, it produces a cloud of debris 15 00:00:47,047 --> 00:00:48,915 that causes an X-ray outburst. 16 00:00:49,315 --> 00:00:51,785 The low-mass object isn't on a circular orbit, 17 00:00:51,785 --> 00:00:53,086 and its motion is affected 18 00:00:53,086 --> 00:00:55,722 by the distortion of space-time near the black hole, 19 00:00:55,722 --> 00:00:58,892 so the eruptions don't repeat over the same exact time frame, 20 00:00:58,992 --> 00:01:01,995 which is what makes them quasi-periodic. 21 00:01:02,228 --> 00:01:04,998 NICER’s observations of Ansky allowed scientists 22 00:01:04,998 --> 00:01:08,134 to probe the gas ejected from the disk after each collision. 23 00:01:08,768 --> 00:01:13,139 They show that it's expelling around a Jupiter’s worth of gas each time. 24 00:01:13,206 --> 00:01:17,143 The gas expands, reaching velocities about 15% 25 00:01:17,143 --> 00:01:18,244 the speed of light. 26 00:01:19,312 --> 00:01:23,116 NICER and other missions will continue to study Ansky 27 00:01:23,116 --> 00:01:24,651 and other QPEs, 28 00:01:24,651 --> 00:01:27,353 helping astronomers reveal their secrets. |