Across
- 2. A large group of stars, planets, and other celestial objects held together by gravity.
- 5. A theory which states that the universe is constantly expanding.
- 7. Emission of energy in waves or particles.
- 8. It is used to classify and range various types of EM Waves.
- 10. Found on the periodic table; They are pure substances made up of only one type of atom.
Down
- 1. The initial atomic particle which was formed in the universe. It makes up protons and neutrons.
- 3. The things which make up our universe. Examples include: Protons, Neutrons, Quarks, and Electrons.
- 4. It is the radiation left over from the Big Bang. It is considered as the oldest microwaves in the universe dating back to 14 million years ago.
- 6. The first element which was formed in the universe.
- 9. Contains all matter and space.