Exploring Our Solar System: Planets and Space for Kids - FreeSchool — Transcript

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1. 0:08You're watching FreeSchool!
2. 0:14Our Solar System
3. 0:19Have you ever looked up into the sky and wondered what was there? Higher than the birds, past
4. 0:24the clouds, and farther than the moon, a whole host of fascinating objects spin in outer space.
5. 0:33Let's imagine for a moment that we can leave the earth behind, and explore the solar system
6. 0:39that surrounds it.
7. 0:43We call it the solar system because everything in it is centered around the sun, and solar
8. 0:48means something to do with the sun. The sun is a star, just like many of the stars that
9. 0:54you can see in the night sky - just many times closer to us. Still, the sun is very, very
10. 1:02far away from the earth; almost 93 million miles away: that's why it looks so small,
11. 1:09even though it's the biggest object in the solar system. In fact, the sun makes up more
12. 1:15than 99 percent of the mass in the solar system. If you put all of the planets, moons, asteroids,
13. 1:23comets, and everything else in the solar system together, they would make up less than one
14. 1:29quarter of a percent of it.
15. 1:32The sun is so big that it's more than 100 times wider than the earth, and if it were
16. 1:37a giant jar you could fit more than one million earths into it.
17. 1:44More than that, the sun is what holds the solar system together. Its massive gravity
18. 1:50is what keeps the earth and all the other planets circling around it instead of drifting
19. 1:55off into space.
20. 1:58The sun is also what allows us to live on Earth. Without the sun, there would be no
21. 2:03heat. There would be no light. Plants could not grow, water would freeze, and nothing
22. 2:09could survive. The sun gives us heat and light because it is always burning: it is a giant
23. 2:16ball of gas, mostly hydrogen and helium, and it burns at millions of degrees in its center.
24. 2:26Let's leave the sun now to explore the planets.
25. 2:32As we move away from the sun, the first planet we will encounter is mercury. Mercury is the
26. 2:39smallest planet in the solar system, much smaller than earth, and one of only five planets
27. 2:45you can see from earth using nothing but your eyes. Of course, it won't look much like a
28. 2:52planet. It looks more like a bright star, and many nights you can see it close to the
29. 2:57horizon near sunrise and sunset.
30. 3:02Mercury is a lot like our moon. It's small and has a rocky surface with craters on it.
31. 3:08It has no moon of its own, and no air to breathe. You probably wouldn't enjoy a visit to mercury,
32. 3:15since temperatures are boiling hot in the sun and freezing cold in the shade. Something
33. 3:21interesting about mercury is that it is the fastest planet to go around the sun - it only
34. 3:27takes 88 days.
35. 3:31Next is Venus, the second planet. Some people call venus earth's sister, because the two
36. 3:37planets are very close in size and gravity, but they are very different on the surface.
37. 3:45First of all, it is very hot. Venus is the hottest planet in the solar system. It's not
38. 3:52as close to the sun as mercury, but its thick atmosphere of carbon dioxide helps it to trap
39. 3:57the heat and stay warmer than its neighbor. It has a thick atmosphere, but it is not one
40. 4:04you could breathe. It is mostly made of carbon dioxide and there are clouds of sulfuric acid!
41. 4:14Venus might not be fun to visit, but it is beautiful to lok at. It is the second-brightest
42. 4:21object in the night sky - the only thing brighter is the moon. If you are looking at a sunrise
43. 4:28or a sunset and suddenly notice what looks like a very bright star, you are probably
44. 4:33looking at Venus.
45. 4:36After Venus comes Earth, the third planet from the sun. Of course, you know all about
46. 4:42Earth, because that's the planet where we live! Earth is what's called a 'goldilocks
47. 4:48planet,' because it's not too hot, and not too cold - it's just right. As far as we know,
48. 4:56Earth is the only planet to have living things.
49. 5:03Let's leave earth again for a moment, though, and visit Mars, the fourth planet from the
50. 5:08sun. Mars is known as the 'red planet,' because iron oxide (a material like rust) in the soil
51. 5:16gives it a reddish color. Mars is smaller than Venus and the earth, but larger than
52. 5:22mercury. It is cold and rocky, with a thin atmosphere made of carbon dioxide and oxygen.
53. 5:29There is water ice on mars.
54. 5:32Scientists are very interested in mars because they think that people could live there with
55. 5:37the help of some special equipment. Rockets and probes have already been sent there to
56. 5:43gain more information about the planet. Right now, there are two special robots exploring
57. 5:50the surface of mars, sending information back to earth.
58. 5:56Mars is the first planet we've visited today besides Earth to have its own moons. It has
59. 6:01two, although they are not big and round like our moon. Mars's moons are small and irregular.
60. 6:10Scientists think they may be captured asteroids. Maybe they came from the big asteroid belt
61. 6:16that is between mars and jupiter. An asteroid belt is a big ring of asteroids, or rocky
62. 6:22objects, orbiting the sun.
63. 6:27Jupiter comes next, the fifth planet in the solar system. Jupiter is the largest planet
64. 6:33and is something called a 'gas giant.' It is called this because it is really big and
65. 6:38made mostly of gasses. Jupiter is so big that you would have to place 11 earths end to end
66. 6:45just to stretch across its middle.
67. 6:49Jupiter is also the third brightest object in the night sky; only venus and the moon
68. 6:55are brighter. You can usually find Jupiter higher in the sky than venus, since Jupiter
69. 7:01is away from the sun and not towards it.
70. 7:06Jupiter has at least 67 moons that circle around it, but 55 of them are very small,
71. 7:14only about as big as a mountain, or smaller. Some of its moons are very large, and at least
72. 7:20two of them are about the same size as the planet Mercury. One of its moons
73. 7:26is the largest moon in the solar system. Some of these large moons can be seen from earth
74. 7:32in your backyard with a telescope.
75. 7:37People cannot land on Jupiter because it is made of gas - there is no ground to land on!
76. 7:43Even if there was somewhere to land, Jupiter is covered by terrible storms, much stronger
77. 7:49than even the strongest storms on earth. One storm that we know about can be seen from
78. 7:55earth. We call it the great red spot because that's what it looks like - and it has been
79. 8:00going on for at least 200 years!
80. 8:06After Jupiter comes Saturn, another gas giant. Saturn is famous for its beautiful rings.
81. 8:15Although they look solid from a distance, the rings are actually made from many, many
82. 8:20small ice particle, as well as rocks and dust.
83. 8:25Saturn also has more than sixty moons orbiting around it, some as large as the planet mercury,
84. 8:31and many smaller.
85. 8:34Something interesting about Saturn is that even though it is very large, it is not very
86. 8:39dense. That means that if you could find a bathtub large enough to put saturn in, it
87. 8:44would float instead of sink!
88. 8:47Saturn is the farthest planet that can be seen from earth without the help of a telescope.
89. 8:56After saturn comes uranus, the seventh planet from the sun. Uranus is another gas giant,
90. 9:03but it is much smaller than Saturn and Jupiter. Unlike any other planet in the solar system,
91. 9:09it is tilted so much that it actually spins sideways! Uranus has rings around it, although
92. 9:17they are much smaller than saturn's, and 27 known moons. Uranus is covered in blue clouds
93. 9:25made of methane, which give it its lovely color.
94. 9:30Very similar to uranus is Neptune, the eighth planet from the sun. Neptune is another gas
95. 9:37giant, and like uranus it has methane in its atmosphere so it also looks blue. Neptune
96. 9:43is a darker blue than uranus and scientists aren't sure why. Neptune has a few thin rings
97. 9:51and 14 moons that we know about.
98. 9:55Because neptune is so far out in space, it takes it a very, very long time to go around
99. 10:01the sun. Remember Mercury, that only takes 88 days to go once around the sun? Poor neptune
100. 10:08takes over 164 YEARS to finish an orbit around the sun. The last time that neptune was in
101. 10:16the same place it is now was before the American Civil War, before computers, phones, airplanes,
102. 10:24or cars had been invented! Neptune has the longest orbit of any planet in the solar system.
103. 10:31Now, you may think that I've forgotten someone - Pluto. Pluto was discovered in 1930 and
104. 10:39was listed as the ninth planet in the solar system. As it was studied longer, scientists
105. 10:45realized how small it is. It is much smaller than any other planet in the solar system,
106. 10:51and even smaller than many other moons. Plus, people started to discover other small, rocky
107. 10:58planet-like objects in space near pluto. Some of them were even bigger than pluto! In 2006,
108. 11:06after 76 years being listed as a planet, Pluto was declared a 'dwarf planet' to show that
109. 11:13it was something that was like a planet, but much smaller. There are at least 6 dwarf planets
110. 11:18in the solar system, and possibly many, many more.
111. 11:24That leaves us with 8 official planets in our solar system: Mercury, Venus, Earth, Mars,
112. 11:35Jupiter, Saturn, Uranus, and Neptune.
113. 11:43I hope you enjoyed exploring the solar system with me today. Goodbye till next time!