Astronomy‎ > ‎

Cosmic Background Radiation

Remember that density is mass / volume. As material cools down it becomes denser since its volume decreases. Water is the exception to this since it is most dense at 4 degrees C. That is why ice at 0 degrees C floats even though it is colder than liquid water. Everything with mass attracts everything else with mass and the greater the mass the greater the gravitational attraction. 
Scientific evidence supports the Big Bang Theory which states that the Universe started out as a very small hot dense area of energy 
that has over the last 13.7 billion years expanded and cooled into the stars, planets, and the galaxies we see today. The CMB (Cosmic Microwave Background) is like a baby picture of our early Universe. It is evidence that supports the Big Bang Theory. 
Microwaves are a type of electromagnetic wave meaning they carry energy just like visible light. They are the waves that carry 
energy that cook food in microwave ovens. Microwaves are longer wavelengths than visible light. 
Cosmic Microwaves are the energy 
that spread out from the Big Bang.    

1. Print this and color the CMB using the key provided.
The coloring sheet is also attached at the bottom of this page.

2. Read about Cosmic Background Radiation here (CMB) and answer the following questions. Use the "next" button at the bottom of the page to read the entire article. Email your teacher ( answers to the following questions then print a copy to bring to class.  

        1. Where did the CMB come from?

        2. Why is the CMB so cold?

        3. Why is the map different colors?

        4. Why is the map of the CMB an oval?

        5. When something is cooled it becomes: a) more dense b) less dense

        6. As mass increases gravity ______.  a) increases b) decreases c) remains constant

        7. The Cosmic Microwave Background is important because: a) it cooks my food, b) is evidence of the Big Bang, c) has neat colors

        8. More dense areas have: a) less gravity so matter collect there b) more gravity so matter collects there c) no gravity so matter collects there.

        9. Colder regions in the CMB are: a) areas were no matter exists b) areas that are less dense so matter collects, c) areas were matter collects due to increased density, d) are more dense areas were matter can’t collect.

        10. The starting points in the Universe for structures such as stars are: a) cold, dense, high gravity regions, b) warm, dense, low
    Lynée Beck,
    Apr 8, 2011, 12:06 PM