Earth, solar, moon: three objects in house whose interactions have a fairly large influence on our lives. Earth orbits the solar annually, and it rotates on its axis about as soon as a day (relying in your definition of “rotate”). This offers us the night-day sequence and the yearly cycle of the seasons.
The moon’s gravitational tug influences the tides. On a month-to-month cycle, we will additionally see the phases of the moon, that are attributable to the relative positions of those three orbs. A full moon makes it potential to see at evening. Earlier than electrical lights, this was a giant deal.
You possibly can see how these interactions construction our entire thought of time. So when you had been writing a science textbook, you’d wish to embody an illustration of the Earth-sun-moon system, proper? However guess what, you’ll be able to’t. The distances and variations in measurement make it virtually not possible.
For instance we wish to construct a mannequin of the solar and Earth alone. Earth has a radius of about 6,371 kilometers (3,959 miles), however let’s symbolize this with a marble 1 centimeter in diameter. To maintain issues in scale, I would have to make use of a large seashore ball for the solar—the sort folks knock round at rock concert events—greater than a meter in diameter. You would match 1.3 million marbles into it.
However wait! It will get worse. That seashore ball would additionally should be 117 meters away. That is longer than a soccer subject. Now attempt to take an image of the ball and the marble. Good luck with that.
Modeling the Earth and moon could be simpler. If we use that marble for the moon, Earth could be a tennis ball, with a diameter of 6.7 centimeters. Now for the enjoyable half. How far aside do you assume we should always put them? Take a guess. You will in all probability be unsuitable as a result of we by no means see the Earth and moon collectively. The reply is 2 meters. This is what that might appear like:
Illustration: Rhett Allain
