1 00:00:00,020 --> 00:00:06,030 [Bell tone] 2 00:00:06,050 --> 00:00:12,080 Launched on October 19th 2008, the Interstellar Boundary 3 00:00:12,100 --> 00:00:18,260 Explorer, or IBEX, spacecraft, is unique in NASA's heliophysics fleet. 4 00:00:18,280 --> 00:00:24,440 IBEX looks at the very edge of the sun's reach, starting at about 8 billion miles away. 5 00:00:24,460 --> 00:00:30,620 This region begins with the termination shock, and ends with the heliopause. Between those two is the heliosheath, 6 00:00:30,640 --> 00:00:36,740 a teardrop-shaped region sculpted by the pressure of the interstellar medium. IBEX is 7 00:00:36,760 --> 00:00:42,770 also different because it makes its images from particles instead of light. Over the course of 6 months, 8 00:00:42,790 --> 00:00:48,810 and many orbits, IBEX can paint a picture of the entire sky in energetic neutral atoms, 9 00:00:48,830 --> 00:00:54,860 or ENAs for short. During its first 5 years, IBEX has made some astounding 10 00:00:54,880 --> 00:00:58,970 discoveries. New narrator: The IBEX mission science 11 00:00:58,990 --> 00:01:03,130 team has used data from the spacecraft to construct the first-ever all-sky map 12 00:01:03,150 --> 00:01:07,190 of the interactions occurring at the edge of the solar system, where the sun's influence 13 00:01:07,210 --> 00:01:11,340 diminishes and interacts with the interstellar medium. The most 14 00:01:11,360 --> 00:01:15,370 startling finding as a result of this map is a bright ribbon of energetic neutral 15 00:01:15,390 --> 00:01:19,400 atoms, emanating toward the sun from the edge of the solar system. 16 00:01:19,420 --> 00:01:23,570 New narrator: New data from NASA's Interstellar 17 00:01:23,590 --> 00:01:27,600 Boundary Explorer, reveal that conditions at the edge our solar system 18 00:01:27,620 --> 00:01:31,670 may be much more dynamic than previously thought. This second 19 00:01:31,690 --> 00:01:35,690 set of all-sky maps show the evolution of the interstellar boundary region. 20 00:01:35,710 --> 00:01:39,730 The mysterious ribbon feature at the nose of the heliosphere 21 00:01:39,750 --> 00:01:43,820 has changed shape, and a knot-like feature has formed. 22 00:01:43,840 --> 00:01:47,990 This variation over time is forcing scientists to try to 23 00:01:48,010 --> 00:01:52,110 understand how the heliosphere can be changing so rapidly. 24 00:01:52,130 --> 00:01:56,220 New narrator: Because IBEX is orbiting Earth, it also can observe 25 00:01:56,240 --> 00:02:00,260 the creation of energetic neutral atoms along the nose of 26 00:02:00,280 --> 00:02:04,320 Earth's magnetosphere. ENAs are created there as solar wind protons 27 00:02:04,340 --> 00:02:08,430 take electrons from hydrogen atoms in the outermost vestiges of our 28 00:02:08,450 --> 00:02:12,500 atmosphere, known as the exosphere. IBEX has also 29 00:02:12,520 --> 00:02:16,580 scanned another nearby world, with surprising results. The moon 30 00:02:16,600 --> 00:02:20,760 has no atmosphere or magnetosphere, so the solar wind slams unimpeded into 31 00:02:20,780 --> 00:02:24,790 its surface. About 10 percent of the impinging solar wind protons 32 00:02:24,810 --> 00:02:28,880 bounce off the lunar surface, becoming ENAs as they do. 33 00:02:28,900 --> 00:02:32,920 New narrator: IBEX has now made the first direct measurements of 34 00:02:32,940 --> 00:02:37,030 hydrogen, oxygen and neon from outside the solar system. 35 00:02:37,050 --> 00:02:41,130 The measurement of these atoms has enabled scientists to get a better grasp on 36 00:02:41,150 --> 00:02:45,180 the environment around our solar system. The speed of the 37 00:02:45,200 --> 00:02:49,260 galactic wind registered around 52,000 miles per hour. 38 00:02:49,280 --> 00:02:53,400 Heavy interstellar atoms show a difference from the solar system and galaxy 39 00:02:53,420 --> 00:02:57,440 as a whole. This puzzle may mean that the sun has moved out of the region 40 00:02:57,460 --> 00:03:01,550 where it formed, or that some of the oxygen has been captured by dust 41 00:03:01,570 --> 00:03:05,730 in interstellar space. 42 00:03:05,750 --> 00:03:09,760 New narrator: New measurements by IBEX have suggested that there is no bow shock to the 43 00:03:09,780 --> 00:03:13,910 heliosphere. The previous understanding of the boundary of the heliosphere was that 44 00:03:13,930 --> 00:03:18,210 outside the influence of the sun, a shockwave was formed by the entire 45 00:03:18,230 --> 00:03:22,370 heliosphere pushing through the interstellar material around it. 46 00:03:22,390 --> 00:03:26,470 New narrator: IBEX recently mapped the boundaries of the solar 47 00:03:26,490 --> 00:03:30,500 system's tail, called the heliotail. If we could look straight down the tail 48 00:03:30,520 --> 00:03:34,600 we would see a shape a little like a four-leaf clover. 49 00:03:34,620 --> 00:03:38,740 The two side leaves are filled with slow-moving particles, and the upper and 50 00:03:38,760 --> 00:03:42,830 lower leaves with fast ones. The entire shape is rotated slightly. 51 00:03:42,850 --> 00:03:46,920 This indicates that as it moves farther away from the sun's magnetic 52 00:03:46,940 --> 00:03:51,100 influence, the charged particles have begun to be pulled into a new 53 00:03:51,120 --> 00:03:55,150 orientation, aligning with the magnetic field of the local galaxy. 54 00:03:55,170 --> 00:03:59,270 New narrator: Recent measurements of the interstellar wind 55 00:03:59,290 --> 00:04:03,450 by IBEX have shown that its direction has changed by about 7 degrees 56 00:04:03,470 --> 00:04:07,530 in only the last 40 years. While the cause of this shift 57 00:04:07,550 --> 00:04:11,660 is unknown, it may be telling us something about the changing conditions as we move 58 00:04:11,680 --> 00:04:15,710 through the Milky Way. New narrator: As IBEX 59 00:04:15,730 --> 00:04:19,810 continues to scan the edge of the sun's influence, who knows what other discoveries it will 60 00:04:19,830 --> 00:04:23,930 make? [Music] 61 00:04:23,950 --> 00:04:27,970 Beeping 62 00:04:27,990 --> 00:04:35,289 Beeping