The Tiny Speck That Is Our Home . . .

Greetings, fellow Earthlings! Did you know our planet was tiny? Take a look at this scale model of the planets in our solar system, arranged in front of a scale model of our sun! Earth is one of the little balls in the bottom right corner! Compared to our sun, or even to a lot of the planets in our solar system, the earth looks miniature!

And this image doesn’t communicate the vast, empty space between the sun and each of the planets. It also doesn’t show that our comparatively giant sun is merely a mid-size star, and that it is just one of 100 million twinkling stars in the sky. Not all those stars are visible from earth, of course!

Your Odds of Successfully Navigating an Asteroid Belt

Most of us have seen Star Wars, where Han Solo flies into an asteroid belt and the tie fighters that follow him get smashed up because it is so hard to fly in an asteroid belt. He is warned by C3PO, his robot companion just how low the odds are of safely navigating it.

To see if that is true, let’s look at the asteroid belt in our own solar system! To get past Mars, NASA missions must navigate this asteroid belt. And even though real-life spacecraft are much too delicate to get hit by an asteroid, they’ve never had a problem whatsoever. This is because in our asteroid belt, the asteroids are usually still hundreds of thousands of miles apart. There are more “rocks” floating around than in other parts of our solar system, but NASA can easily navigate through them. Sorry, C3PO, the odds of successfully navigating an asteroid field is much higher than 3,720 to 1!

Han Solo navigating through an asteroid field in Empire Strike Back (Image: © Lucasfilm)

There’s No Gravity in Space?

We say this all the time, because we see videos of weightless astronauts floating in the space station, or jumping about on the moon. But those astronauts that jump on the moon don’t go off endlessly in that direction, which would happen if there were no gravity. They are pulled back by the moon’s gravity, even though it is just a small fraction of the earth’s gravitational pull. And those astronauts on the space station are in orbit around the earth . . . because of gravity!

So there isn’t no gravity in space, there is less gravity!

Astronaut Michael Foale, one-time record holder for most cumulative time in space by a U.S. astronaut. That’s a lot of floating! (Image: © NASA)

Can You See the Great Wall of China from Space?

The Great Wall of China is often said to be the only man-made object visible from space. It makes sense that people would have said this, even centuries before we ever went into space. Though much of it is in ruins today, the Great Wall wall is said to be over 13,000 miles long. But astronauts have said again and again that they have great difficulty actually finding it.

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Which falls faster, a hammer or a feather?

Does as heavy object fall faster than a lighter one? What about a much lighter one? Check out this video clip where astronauts on the moon find out!

Apollo 15 Astronaut David Scott performing a science demonstration on the moon in 1971!

During the Apollo 15 mission on the moon, Commander David Scott performed a science demonstration for all the world to see! He dropped a geologic hammer and a falcon feather and dropped them at the same time. Which do you think hit the ground first?

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Is There Sound in Space?

Is it possible to hear sounds in space? The short answer is no . . . mostly! ?

A scene from 2001: A Space Odyssey, one the few science fiction movies to depict total silence in its scenes in space, and also one of Mr. Yuck’s favorite movies!

In almost every science fiction movies or TV show, you hear spaceships speeding through space or shooting laser beams. That is entertaining, but sound doesn’t work this way in real life. Sound doesn’t travel in a vacuum, and much of space is a vacuum, so that should be an easy answer.

But . . . to be completely correct, not all of space is a vacuum. It’s full of clouds of gas and dust that are the remains of old stars or the beginnings of new ones. And sometimes that gas is dense enough to carry sound waves, just not sound perceptible to humans.

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Is the Sun Yellow?

Typical representation of our yellow sun!

We all reach for the yellow crayon when it’s time to draw the sun, right? And we know the sun is yellow because Superman gets his superpowers from a “yellow star.”

But light is a tricky thing! In space, the sun would appear white. By the time we see light from the sun, it has traveled 92,955,807 miles through space and through our atmosphere, which bends and filters light.

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