What If We Had No Moon

It seems like a reasonable question to ask. What if we had no moon? Would it matter? What has the moon done for me lately?

It turns out that the presence of such a large moon as we have is unusual for a terrestrial planet. Mercury and Venus have no moons, and Mars has two tiny moons, Pho-bos and Deimos. To have a moon roughly H the size of the planet is unique in the inner solar system. Our Moon, for example, is as large as some of the moons of the giant gas planets in the outer solar system. If there were no moon, we would have no ocean tides, and the rotation rate of the earth would not have slowed to its current 24 hours. It is thought that early in the life of the Earth, it rotated once every 6 hours. The moon also appears to stabilize the rotational axis of the Earth. The Moon, in periodically blocking the light from the Sun's photosphere gives us a view of the outer layers of the Sun's atmosphere, and it also gave early astronomers clues to the distribution of objects in the solar system.

Close Encounter

Close Encounter

Did you ever wonder why the sun and the moon are the same size in the sky? In actual physical size, the sun dwarfs the moon, but the sun is so much farther away, that the two appear the same size. Try this: Hold a dime and a quarter in front of your face. Now move them back and forth until they appear to be the same size. Which do you have to hold farther away for this to be true? The bigger one, of course! We happen to be on the earth at a time when the moon exactly blocks the light from the sun's photosphere during a solar eclipse. As the moon slowly drifts away from the earth, it will get smaller and smaller in the sky, and people will be right when they eventually say, "Solar eclipses just aren't what they used to be."

Telescopes Mastery

Telescopes Mastery

Through this ebook, you are going to learn what you will need to know all about the telescopes that can provide a fun and rewarding hobby for you and your family!

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