Fun Science: Space
Professor Gizmo (Amazing Science Presentations) gives expert video advice on: Why do we need to wear a space suit in space?; Why do things float around in space?; Why do stars twinkle? and more...
What is "outer space"?
Outer space, I guess refers to outer space when they're thinking about things beyond our Earth. Once you get outside our Earth's atmosphere, I consider that outer space. Outer space is the region above our atmosphere. There's no air up there, you can't hear sound, and you get into the region of moons, planets, solar systems, stars, galaxies, and black holes; that's all in outer space.
What is the "Milky Way"?
I think you can get a pretty good look at the Milky Way if you get away from the city, lay down in the field, and look to the south and to the west. You'll see this area of the sky that's just full of stars. Now, we are part of the Milky Way, but we're on an edge of the Milky Way. So when we see the Milky Way, we're looking through thousands and thousands of stars that are sitting above us. We're on the edge of it looking through. The Milky Way is a galaxy, and a galaxy is just basically thousands of stars all together in one group.
What is the "solar system"?
Our solar system is basically composed of all the planets and moons that are orbiting our sun. We had 9 planets at one time, and now I think we're down to 8, but the planets are large bodies that are orbiting around the sun. Many of them have different rates of time that it takes for them to get around the sun. They each have moons, which go around each of those planets. We have one moon. Some planets have many moons. Some planets have no moons. But all of these things which are basically part of and are affected by the sun are part of our solar system.
Why do we need to wear a space suit in space?
Well, you've heard of these guys going into space? Twenty million dollars for that suit - no, just kidding! But you do need a suit to go into space. If you're going to get outside of the space craft you do need a suit. There's no air; there's no atmosphere; there's no pressure on our body. Plus out in space, because there's no air, there's a regulation of temperatures right from the sun. One side of you would be extremely hot. The other side would be very very cold. So you need this special suit to protect your from pressure, from heat, and even particles that might be flying around in space. So you have to protect yourself. And if you didn't have the suit, you couldn't even breathe. There's no air.
Why do things float around in space?
When things are in space, you consider them floating around but they're probably being affected by some other large mass in space. They're floating around because they're not near another very large object which would create a gravity for them. They probably are being affected by a planet but very slightly and they might be moving towards a planet or moving towards a moon. In space, you feel like you're weightless because you're so far away from a large mass which kind of takes us away from gravity.
Are there wormholes in space that we can use for time travel?
Can you use a wormhole when traveling in space? I kind of doubt it. A wormhole might be off in another dimension, but we have length, width, and depth. Those are the three dimensions. Some people consider time the fourth dimension, but I don't know about wormholes for traveling in time. That's in the theoretical end of things. You might want to look into that. You could get into it, study that and see where that would take you. But there are black holes in space, but I don't know about the wormholes.
Why do stars twinkle?
The twinkling of the stars is mainly caused by the light travelling such a long distance. When it finally reaches the Earth, and this could take years and years to reach. But, when it finally reaches the Earth it has to pass through the atmosphere. The atmosphere has dust and particles in it, and sometimes the light takes on a little bit of an optical illusion and it gives this off and on effect and so the stars appear to twinkle. Objects that are closer in the sky, like the moon and some of the other planets, they do not appear to twinkle because that light is not travelling as far as a star's light would travel.
What are "shooting stars"?
If you have never seen a shooting star, it would look like a light that would appear in the sky and then just start moving across the sky. Sometimes they move at tremendous speeds. So when you see a shooting star, you're really not seeing a shooting star, but you are seeing a particle falling from space, and that particle is being heated up by the earth's atmosphere to thousands of degrees. This shooting star gets very hot, and gives off lots of light. The shooting star just disintegrates a lot of the time, but occasionally it doesn't fall to the earth. So shooting star is misnamed but they sure are nice looking in the sky.
What is a "blue moon", and will it make me sad?
No, a blue moon will not make you sad. A blue moon is a term that simply refers to the fact that the moon will have its full moon phase twice in one month, and the moon's phases are once every 28 days so that rules out ever having a blue moon in the month of February.
How are planets named?
If you go to the past when things were named a long time ago, they primarily relied on mythology. They used mythological names to name moons and planets. Now, today when they name things that are discovered in space they have to follow a certain protocol. They now give numbers to planets so that everything can be classified and kept orderly.
Why is Mars red?
Mars is basically red because it's really rusty, and it's old is not the answer. Mars is actually red because of the type of rock that's on the surface, and that it has a lot of iron in it and it gives that effect of this red look. It's not really rusty.
Can I hear sound in space?
No, you cannot hear sound in space, as sound is a vibration. Any object can vibrate as vibration is just something moving back and forth. If it goes back and forth fast enough, it disturbs the air enough so that it moves through the air and gets to our ears. So, if you're in space, and something is vibrating and there's no air around, we can't hear it, because a sound is basically the vibration of something that vibrates the air and then our ears can pick it up. Without air in space, we can't have any sound.
What is in space instead of air?
Well, in space there is the lack of air. There are some tiny molecules and other things out there, but the air in our atmosphere is really concentrated around the surface. As you go further out in space there's less and less air, and so, basically, when you get out into space, and it's called a vacuum, it is the lack of particles, the lack of substance there. So, vacuum is nothing.
What is air made up of?
You have mostly Nitrogen, some Oxygen, some Carbon Dioxide, and a whole bunch of other gases that are mixed in the air. It's very thick, and without air it's like driving down a highway and sticking your hand out the window; it's going to get pushed back. In air, you have lots of particles at the surface of the earth. We're in air, we're in atmosphere, and it's very thick. It's almost like we're living at the bottom of an ocean of air. It's pushing down on us and creates pressure. You can't see air, but you can see the effects of air. If you move through the air very fast, you can feel it. Wind is blowing, you can feel it. Wind is blowing on a tree, you can see it moving. But you can't see the air itself. All you can do is see the effects of the air and the wind, or if you're moving through the air very fast.
How do satellites send messages through space?
Satellites will send messages through space the same way a radio station on earth sends signals to your radio, or television stations send signals to your television. It's electronic signals that travel through air, space, and so when there are satellites that are up in space and they're picking up information, that information is sent to us by a signal from the satellite to the earth that we receive with radio receiving equipment.
What are the "Northern Lights"?
I don't know if you've ever seen the Northern Lights but they're absolutely beautiful. Certain times of year under certain conditions, especially after a solar flare, which is kind of a storm on the sun, it sends off all kinds of material out in space. As that material gets to the earth, what happens is it gets attracted to the poles of our earth. These cosmic rays that are coming from the sun are pulled down at the polar region because of the magnetic north pole. As they come through the earth's atmosphere, they create Aurora Borealis in the Northern Lights. They create these flashing, dancing, colorful lights. They're usually seen brighter near the north pole. Sometimes if you get a real large eruption from the sun you will see these further south towards the equator but most of the time you have to live in a northern latitude before you can see the Northern Lights.
What is the magnetic north pole?
Our planet earth has two poles; the north pole and the south pole. It's just like a magnet, and it's not exactly where the north pole or south pole is. It's a little bit off from there. But there is the north pole and the south pole that the earth spins on, and then there's a north magnetic pole and a south magnetic pole where a compass needle will point to.