1 00:00:00,050 --> 00:00:04,059 Music 2 00:00:04,080 --> 00:00:08,070 Music 3 00:00:08,090 --> 00:00:12,080 Music 4 00:00:12,100 --> 00:00:16,079 Alex: Solar flares and coronal mass ejections do 5 00:00:16,100 --> 00:00:20,110 not always hit Earth. They happen all over the sun and depending 6 00:00:20,130 --> 00:00:24,169 on where on the sun they occur determines whether or not they're 7 00:00:24,190 --> 00:00:28,200 going to travel towards the Earth. Phil: Some of them could be shot off to the side, and just miss 8 00:00:28,220 --> 00:00:32,210 us completely. They could go up, they could go left. Some are 9 00:00:32,229 --> 00:00:36,300 like curveballs, that a pitcher will throw. They could 10 00:00:36,320 --> 00:00:40,310 seemingly come straight for us, and then miss us completely. 11 00:00:40,330 --> 00:00:44,330 Alex: Space weather can have several different effects on the 12 00:00:44,350 --> 00:00:48,360 Earth and the near-Earth environment. In space, it can create 13 00:00:48,380 --> 00:00:52,410 dangerous radiation in the form of particles, which is detrimental 14 00:00:52,430 --> 00:00:56,430 to the health of astronauts. These particles, 15 00:00:56,450 --> 00:01:00,510 as well as solar flares, can cause cause damage to 16 00:01:00,530 --> 00:01:04,590 satellites in near-Earth orbit. In addition, 17 00:01:04,610 --> 00:01:08,640 electromagnetic disturbances created by geomagnetic storms 18 00:01:08,660 --> 00:01:12,670 can affect power transmission on the ground, can also 19 00:01:12,690 --> 00:01:16,750 disrupt communication. But space weather has 20 00:01:16,770 --> 00:01:20,850 no direct effect on human beings themselves. Holly: We are protected 21 00:01:20,870 --> 00:01:24,910 here on the surface of the Earth from solar flares and coronal mass ejections 22 00:01:24,930 --> 00:01:28,930 when they impact the Earth, due to the magnetic field of the Earth called the 23 00:01:28,950 --> 00:01:32,960 magnetosphere, which deflects the magnetic field and the energetic particles 24 00:01:32,980 --> 00:01:36,990 as well as the atmosphere, which absorbs the higher levels of 25 00:01:37,010 --> 00:01:41,050 radiation. Phil: Most of the energy that's associated with a solar flare or 26 00:01:41,070 --> 00:01:45,080 coronal mass ejection doesn't even reach the surface of the Earth. So even 27 00:01:45,100 --> 00:01:49,100 the biggest of flares isn't going to affect you here at Earth. 28 00:01:49,120 --> 00:01:53,120 Music. Alex: When a large solar eruption 29 00:01:53,140 --> 00:01:57,170 occurs, there are generally three things that happen. Each of these takes 30 00:01:57,190 --> 00:02:01,200 a different amount of time to reach the Earth. The solar flare, because 31 00:02:01,220 --> 00:02:05,220 it's light, travels at the speed of light and takes approximately 8 minutes to reach 32 00:02:05,240 --> 00:02:09,259 us. The solar energetic particles are traveling extremely fast 33 00:02:09,280 --> 00:02:13,290 --close to the speed of light, but not exactly the speed of light--so they take 34 00:02:13,310 --> 00:02:17,330 roughly 20 to 30 minutes to reach us. 35 00:02:17,350 --> 00:02:21,350 The coronal mass ejection is much slower, and that takes about 36 00:02:21,370 --> 00:02:25,380 1 to 4 days to reach us. Music. 37 00:02:25,400 --> 00:02:29,460 Holly: The sun goes through what we call a solar activity cycle, 38 00:02:29,480 --> 00:02:33,570 where every 11 years on average, it will go from a very low period of 39 00:02:33,590 --> 00:02:37,610 solar activity--meaning sunspots and solar storms--to another period 40 00:02:37,630 --> 00:02:41,650 of low activity, and in-between it goes through what we call solar maximum. At solar 41 00:02:41,670 --> 00:02:45,670 maximum the sun has a very complicated magnetic field structure, and 42 00:02:45,690 --> 00:02:49,690 therefore it creates a lot more sunspots and a lot more solar storms like flares, 43 00:02:49,710 --> 00:02:53,730 and CMEs. It's very important to be able to 44 00:02:53,750 --> 00:02:57,760 forecast solar events because they can affect our technology, our 45 00:02:57,780 --> 00:03:01,800 satellites, they can cause power grids to be affected. So as we 46 00:03:01,820 --> 00:03:05,829 become more and more technologically advanced, it becomes more important to be able to forecast 47 00:03:05,850 --> 00:03:09,840 such events. Music 48 00:03:09,860 --> 00:03:13,860 Music 49 00:03:13,880 --> 00:03:17,940 Beeping 50 00:03:17,960 --> 00:03:27,350 Beeping.