1 00:00:00,170 --> 00:00:01,430 - [Instructor] You're probably familiar 2 00:00:01,430 --> 00:00:05,080 with the major types of planets in our solar system. 3 00:00:05,080 --> 00:00:07,650 You know, there are some smaller rocky planets 4 00:00:07,650 --> 00:00:09,660 and some giant gas planets. 5 00:00:09,660 --> 00:00:13,380 The rocky, or terrestrial ones are closer to our star, 6 00:00:13,380 --> 00:00:16,810 the sun where it's much warmer, while the giant gas planets 7 00:00:16,810 --> 00:00:18,530 are farther out in the cold. 8 00:00:18,530 --> 00:00:22,090 But what about other planet systems we're finding out there 9 00:00:22,090 --> 00:00:23,390 among the stars? 10 00:00:23,390 --> 00:00:26,840 For the most part, they don't look a whole lot like ours. 11 00:00:26,840 --> 00:00:30,050 Turns out, there doesn't seem to be a typical arrangement 12 00:00:30,050 --> 00:00:31,800 for planetary systems. 13 00:00:31,800 --> 00:00:35,660 Yep, all planetary systems might be weird. 14 00:00:35,660 --> 00:00:37,410 Most other systems of planets 15 00:00:37,410 --> 00:00:39,980 are certainly arranged differently. 16 00:00:39,980 --> 00:00:42,550 Sure there are lots of planets out there the size 17 00:00:42,550 --> 00:00:44,530 of Juipter and Neptune and Earth, 18 00:00:44,530 --> 00:00:47,980 but their Jupiters and Neptunes can be way closer 19 00:00:47,980 --> 00:00:49,870 to their stars than ours. 20 00:00:49,870 --> 00:00:53,950 Some as close or closer than the orbit of Mercury. 21 00:00:53,950 --> 00:00:56,680 So scientists who study these exo-planets, 22 00:00:56,680 --> 00:00:59,910 planets outside our solar system, find themselves using 23 00:00:59,910 --> 00:01:03,860 terms like Hot Jupiters and warm Neptunes. 24 00:01:03,860 --> 00:01:06,840 Plus, there's a whole range of exo-planet sizes 25 00:01:06,840 --> 00:01:09,860 from much smaller than Earth to even bigger than Jupiter. 26 00:01:09,860 --> 00:01:11,850 To help describe what weight class each 27 00:01:11,850 --> 00:01:14,410 of these planets belong to, we often refer back 28 00:01:14,410 --> 00:01:17,210 to the different planet types in our solar system 29 00:01:17,210 --> 00:01:19,300 using terms like Mini Neptunes 30 00:01:19,300 --> 00:01:22,690 and Super-Earths or Super-Terrestrials. 31 00:01:22,690 --> 00:01:25,360 We're constantly learning more about exo-planets 32 00:01:25,360 --> 00:01:28,730 and our ideas about them are changing as we go, 33 00:01:28,730 --> 00:01:31,670 ideas about how these different planet types relate 34 00:01:31,670 --> 00:01:34,110 to each other and what their variety can teach us 35 00:01:34,110 --> 00:01:36,923 about our own weird little solar system.