Substances in Space

Introduction: Have you ever wondered what would happen to different stuff if you brought it into outer space?  How do you think the conditions would be different?  Could you still eat your M & M's and drink your Sprite?  Well, we know that the environment in space is much different than it is here on earth. For one thing, the temperatures in space are much more extreme.  In areas that are lit by the sun,  temperatures can be extremely hot (over 120 C) but areas shadowed from the warmth of the sun are usually very cold (up to -100 C).  You could go from having melted M & M's to frozen Sprite in a hurry.  In addition, there is no atmosphere (air) in space because their is no gravity to keep air molecules close together.  Without air, there is no (air) pressure and we often refer to space as being a "vacuum". 

  In this exploration, you will explore what happens to substances when you decrease the amount of air that is around the substances to create a vacuum similar to the one we find in space.   While we can't create a perfect vacuum in class, we can create a simple system that will reduce the air pressure by about 500%.  This will reduce the air pressure to about 20% of normal - more than enough to get a good idea of how substances will behave in the "vacuum" of outer space.  

National Science Standards

Big Idea: Nature is predictable and we can use evidence and models to develop explantions to understand our world (evidence, models, explanation) 

Physical Science: Objects have many observable properties including size, weight, color, and the ability to react with other substances. 

Georgia Performance Standard's 

Science: 

Students will use the ideas of systems, models, change and scale to explore (S(K-5)CS4) 

Change happens to things on, above and below the earth. (S2E3) 

Materials (objects) can change - melt, evaporate, dissolve, rust. (S2P1)

Mathematics:  

Students will pose questions, collect data, and organize and record results. (M(K-5)D1  

Materials:

10-20 ml syringes                    Sprite (fully carbonated)              M & M's            Ruler

Miniature Marshmallows         Science Notebook/Journal         Paper Towels   Cups 

Exploration:  

Procedure: 

1. Since astronauts love junk food, we will start out by testing M& M's, Marshmallows, and Sprite.  But before you begin this activity, you must carefully observe/measure each substance and record your description of them. Write down these descriptions on your Substances in Space Sheet or your science journals.

2.  Next, discuss your ideas with your group and make some predictions regarding what you expect to happen to each of these substances when the go "into space". Consider how the unique properties of each substance might cause it do react differently in space.    Write down your predictions on your Substances in Space Sheet or your science journals.   

3. Starting with an M & M, place one into your syringe and then push the extra air out of the syringe until there is only space for the M & M. Next, tightly place your thumb over the opening of the syringe and gently use your other hand to slowly pull back the syringe.  By increasing the amount of space inside the syringe without letting any air in, you decrease the air pressure inside and create a space-like vacuum.   Carefully observe the M & M inside the syringe and record any changes in properties that you can see.  Finally, remove the M & M from the syringe and record any changes that occur after the vacuum has been broken.

4. Repeat this process using the miniature marshmallow and record your observations.   

5.  For the Sprite, push the syringe in completely and then place the tip into the cup of Sprite and pull it back until  to it is about 1/5th or 20% full. Then repeat the process as before and record your observations.   Since young children might have a difficult time with this step, you may choose to do it as a demonstration. 

Guiding Questions:

1. Explain why you think the M&M did not change much?

    3.   Explain the changes that you observed with the Sprite?

    4.  If our bodies were exposed to a similar vacuum, do you think they would act more like the M & M's, marshmallows, or Sprite. Justify your answer.

Explanation:

This is a great activity because it is fun engaging for students and they get to simulate some of the conditions that exist in space.  As we continue to explore and work more in space, we will need people who understand the unique and challenging conditions that exist in such places.  While students often recognize that humans have to take their oxygen with them because there is no "air" in space, they often don't realize that, without this air, there is also no atmospheric pressure in space.  Since our bodies have been designed to function under this atmospheric pressure, this outside pressure is just as important to our survival as oxygen. Without enough atmospheric pressure, the fluids in our body will quickly start to heat up and boil.   By examining how a variety of substances act in a vacuum, students can infer for themselves how the human body would react in similar situations.      

In order to avoid these disasters, scientists have designed spacesuits to perform in the varying conditions of space. Today's spacesuits are pressurized, have an oxygen supply, and insulate astronauts from the severe temperature changes experienced in space.  These suits, called extravehicular mobility units (EMU's) are even designed to protect astronauts from the bombardment of tiny meteoroids that often occur during space walks.  

Extension and Connections:

In regards to space, students should think of other ways that the environment there is different and how these changes might affect them and the objects found in space. Students could also brainstorm to think of areas on the earth where there the atmospheric pressure might be higher or lower than normal.  For example, high in the mountains the pressure is significantly less due to the fact the air is less dense (thinner) (with less gravity the air particles aren't pushed as close together).   Deep in the ocean, the pressure is increased dramatically and students can discuss how these changes would effect them and the organisms that live there.   

Teacher’s Guide: Syringes can be purchased inexpensively or donated from local pharmacies or science supply companies.   With older students, you may want to discuss what happens to our bodies in space in more detail. If your students have seen movies such as Total Recall, they may be under the false impression that their bodies would suddenly balloon-up and their eyes would pop out when exposed to the vacuum of space.  Actually, the bodies response is less dramatic although death would occur quite quickly. Since our bodies are mostly liquid water, we would act in a manner similar to the Sprite. Our death would probably be caused by dissolved gasses that bubble out from our blood and body fluids, in a similar manner to a diver who has the "bends".  Even the water in our bodies would begin to vaporize starting with the skin and moving inwards.  We would be confused after 15 seconds, unconscious after 20, and death would occur in about 80 seconds. Sure glad we have those spacesuits.  

Substances in Space  Chart