To Scale: The Solar System
About this video
Pictures of the solar system are never to scale, because at true scale the planets would be too tiny to see. Two filmmakers build a scale model in the Black Rock Desert, with a marble-sized Earth and seven miles of space, and show that from Earth's orbit the model Sun looks the same size as the real Sun. They link the model to astronauts seeing the whole Earth as a tiny marble.
You'll be able to
- explain why most pictures of the solar system are not to scale.
- describe how much empty space there is between the planets.
- explain how the filmmakers checked their model's proportions.
Key words
- to scale
- When sizes and distances in a model are shrunk by the same amount as the real thing.
- scale model
- A smaller copy where every size and distance keeps the same proportions as the real thing.
- orbit
- The path a planet takes around the Sun.
- proportions
- How the sizes of things compare with each other.
Transcript
If you look up an image of the Earth and moon, you're gonna get a picture where they're quite close together. Something like that. But, in reality, the Earth and moon are that far apart. That is the Earth and the moon to scale. Taking the same concept but for the solar system, every single picture of the solar system that we ever encounter is not to scale.
If you put the orbits to scale on a piece of paper, the planets become microscopic, and you won't be able to see them. There is literally not an image that adequately shows you what it actually looks like from out there. The only way to see a scale model of the solar system is to build one.
Welcome to Black Rock Desert. This is Alex, I'm Wylie, he's going to be behind the camera, I'm gonna be probably making a lot of mistakes on camera... We have 36 hours to measure the distances, trace out the orbits, and set up a time lapse shot from up on top of a nearby mountain.
To create a scale model with an Earth only as big as this marble, you need seven miles of empty space. So that's why we're here. Why did you guys come? I don't have a job... At this scale, the Sun is a meter and a half so about that big around... We are driving right now to Mercury, ... and we've arrived.
Venus is the same size as Earth... I have the world in my pocket somewhere... And Earth. And this is Mars. Got a couple of robots rolling around on that one. Once the time lapse is ready, we'll drive each orbit with a light, hopefully you'll be able to tell just how big they really are.
Onward to the outer planets. Jupiter Saturn That tiny light out there is our Sun, just over a mile away. The Sun is way, way out there now. This is it, the edge of the solar system. Right now, it's about 7 a.m., we just woke up right before the Sun is about to rise...
We are on Earth's orbit, Wylie is over there holding our Sun, cue the dramatic sunrise music. So if we've made our model correctly, your perspective from where Earth is on the model, will match your perspective from standing on the real Earth. So if you look back at the sun, you will see that the model sun and the real Sun are the exact same size.
That's how you can tell that the proportions are correct. There are 24 people in the entire history of the human species who have actually seen the full circle of the Earth with their own eyes.
News: "Following the breakfast the astronauts went to the suit room where they donned their space suits..."
Cronkite: "This is Man's attempt to get to the moon..."
Announcer: "We have liftoff..." In Earth orbit the horizon is just slightly curved. When you head on out to the moon, that horizon slowly curves around and upon itself, and all of a sudden you're lookin' at something that is very strange, but very very familiar...
Astronaut: "Oh my god look at that picture over there..." "Wow is that pretty!" You can put your thumb up, and you can hide the Earth behind your thumb. Everything that you've ever known. All behind your thumb. Not any bigger than that, way up there. It's really beautiful.
I mean you can cry. That's what I really wanted to try and capture. We are on a marble, floating in the middle of nothing. When you come face-to-face with that, it's staggering. Subtitles by the Amara.org community
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