Cosmic Microwave Background Radiation
Cosmic Microwave Background Radiation (CMB) is electromagnetic radiation that fills the universe and is a remnant from the early stages of the universe. It is often referred to as the "afterglow" of the Big Bang, as it is the oldest light in the universe. CMB is made up of microwaves and has a nearly uniform temperature of approximately 2.7 Kelvin.
Key Concepts:
- Discovery: CMB was first discovered in 1965 by Arno Penzias and Robert Wilson, who were awarded the Nobel Prize in Physics for their discovery.
- Origin: CMB is thought to have originated about 380,000 years after the Big Bang, when the universe cooled enough for neutral atoms to form and the photons were able to travel freely through space.
- Uniformity: The uniformity of the CMB temperature across the sky provides strong evidence for the Big Bang theory and the subsequent expansion of the universe.
- Scientific Significance: Studying the CMB has provided valuable insights into the early universe, the formation of galaxies, and the composition of the cosmos.
Study Questions:
- What is cosmic microwave background radiation and how is it related to the Big Bang theory?
- Who were the scientists credited with the discovery of CMB, and what was the significance of their discovery?
- Explain the uniformity of the CMB temperature across the sky and its implications for our understanding of the universe.
- How has the study of CMB contributed to our understanding of the early universe and the formation of galaxies?
Further Reading:
For further reading on cosmic microwave background radiation, you can explore the following resources:
.◂Science Worksheets and Study Guides Third Grade. Animals and their needs
Study Guide
Animals and their needs 
Worksheet/Answer key
Animals and their needs Worksheet/Answer key
Animals and their needs Worksheet/Answer key
Animals and their needs Vocabulary/Answer key
Animals and their needs
Worksheet/Answer keyWorksheet/Answer keyWorksheet/Answer keyVocabulary/Answer keyThe resources above cover the following skills:
LIFE SCIENCE
From Molecules to Organisms: Structures and Processes
Create representations to explain the unique and diverse life cycles of organisms other than humans (e.g., flowering plants, frogs, butterflies), including commonalities such as birth, growth, reproduction, and death.
Unity and Diversity
Construct an argument from evidence to explain the likelihood of an organism’s ability to survive when compared to the resources in a certain habitat (e.g., freshwater organisms survive well, less well, or not at all in saltwater; desert organisms survive well, less well, or not at all in woodlands).
Create models that illustrate how organisms and their habitats make up a system in which the parts depend on each other.