July 20th, 2019 marks the 50th anniversary of the Apollo 11 mission, a small step for man, but a giant leap for humankind. In the past 50 years we’ve learned so much more about our planetary satellite neighbor, and to celebrate this anniversary, we’re sharing some OUT OF THIS WORLD facts about the moon:
1. Our moon is the 5th largest moon in the Solar System
2. The moon is not part of Mars.
3. The moon used to be part of the Earth, until a Mars-sized planetesimal hit our planet, sending a cloud of hot rock into space that eventually cooled, consolidated, and turned into our moon.
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| Image Credit: Joe Tucciarone (via NASA) |
4. Earth’s tilted axis is likely a result of this collision.
5. Katherine Johnson, one of only a few black “human computers” employed by NASA for 33 years, calculated the Apollo 11’s trajectory to the moon and many other missions involving human space travel.
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| Image Credit: NASA |
6. The moon used to look much, much bigger, because it was closer to Earth. Research suggests the moon could have been up to 12 times closer to Earth than it is now.
7. Because it takes the moon ~27.3 days to both rotate and revolve around the Earth, we always see the same side of the moon. Before the space age, no one had seen the other side.
8. Without the moon, oceans on Earth would not have tides.
9. The moon not only causes tides in the oceans, it also causes tides in rocks.
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| Image Credit: NASA/JPL |
10. There is ice on the moon. It’s primarily concentrated inside craters at the north and south poles.
11. We’re not totally sure where this ice came from.
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| Image Credit: NASA |
12. Apollo 14 astronauts brought back an Earth rock from the moon (more on that here).
13. The moon has its own time zones. In 1970, astronomer Kenneth L. Franklin designed a watch that measures time based on the period it takes for the moon to revolve around the Earth. It’s called a lunation.
14. The moon is not round. It’s actually shaped more like an egg (or according to some, a lemon)
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| Image Credit: NASA/Goddard |
15. Scientists recently found a large dense blob of metal below the moon’s surface.
16. Moonbows are a thing. A lunar rainbow occurs when light from the moon illuminates the water in our atmosphere, creating a spectrum of color.
17. Moons that escape the force of gravity of their planets are referred to as ploonets.
18. The lunar ionosphere, a region of its atmosphere full of ionized gases, is surprisingly dense.
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| Image Credit: NASA |
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| Image Credit: NASA (via Giphy) |
25. Some astronauts have had an allergic reaction/hay fever symptoms after interacting with moon dust.
26. There are over 190 moons in our solar system.
27. Billions of years ago, the moon had a magnetic field at least as powerful as Earth’s.
28. Astronauts have left a lot of objects on the moon, including golf balls, feathers, and bags of human waste.
29. The moon’s temperature can reach as high as 123 degrees Celsius, to as low as -233 degrees Celsius.
30. NASA has collected 2,200 samples of rocks, pebbles, sand, and dust from the moon’s surface.
31. There is a surprising amount of water locked inside minerals from moon rocks.
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| Image Credit: Griffith Observatory |
33. Shadows on the moon are darker than they are on Earth. This is because on Earth, our atmosphere efficiently scatters light, meaning that shadowed areas are still slightly lit. Because the moon has no atmosphere, light isn’t scattered.
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| Image Credit: Jesse Berry (via Wikimedia Commons) |
35. The moon is slowly drifting away from Earth, at a rate of about 3.78 cm per year.
36. The tallest mountain on the moon is Mons Huygens, at 18,046 ft (that’s about half the height of Mt. Everest).
37. All lunar craters must be named under a specific naming scheme.
38. Because there is no wind on the moon, footprints on the lunar surface are still intact and in pristine condition.
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| Image Credit: NASA |
40. The moon is surprisingly rich in a rare isotope called helium-3.
41. The moon is shrinking.
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| Image Credit: Smithsonian Institution |
43. 30 Earth-sized planets could fit between the moon and Earth on average.
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| Image Credit: Science Bob (via ScienceBob.com) |
45. The moon landing was not faked. C’mon guys.
46. The original video of the 1969 Apollo 11 Moon landing and the first human steps on the moon will be available on NASA TV at the actual times these two events took place 50 years ago – 4:02 and 10:38 p.m. respectively. The video also will stream live on Twitter, Periscope, YouTube, Facebook Live and UStream.
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| Image Credit: Shuran Huang (via NPR) |
48. A felt-tipped pen saved the Apollo 11 astronauts.
49. It would cost $30 billion USD to go back to the moon. Do you think we should?
50. A Moon Pie has never been on the moon, but they really want to go. We 100% support this.
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| Image Credit: MoonPie |