Page 5 - Curriculum Visions Dynamic Book

Our SUn, which is a star, and its planets, moons, comets, asteroids, and other small bodies all lie in just one arm of one of the galaxies.
The cosmos does not, however, contain only things we can see in visible light. In fact, most of the cosmos is invisible to us. It includes things we will discuss later in the book, such as dark matter and black holes, and it also contains waves of radiation, such as X-rays and strong force fields such as gravity and magnetism. All of them play a vital role in the way the cosmos works.
asteroid Any of the many small objects within the Solar System.
black hole An object that has a gravitational pull so strong that nothing can escape from it.
comet A small object, often described as being like a dirty snowball, that appears to be very bright in the night sky and has a long tail when it approaches the Sun.
cosmos The Universe and everything in it. The word “cosmos” suggests that the Universe operates according to orderly principles.
dark matter Matter that does not shine or reflect light.
earth The third planet from the Sun and the one on which we live.
galaxy A system of stars and interstellar matter within the Universe.
gravity The force of attraction between bodies. interstellar Between the stars.
magnetism An invisible force that has the property of attracting iron and similar metals.
matter Anything that exists in physical form. milky Way The spiral galaxy in which our star
and Solar System are situated.
nebUla (pl. nebUlae) Clouds of gas and dust that exist in the space between stars.
radiation The transfer of energy in the form of waves (such as light and heat) or particles (such as from radioactive decay of a material).
radio telescope A telescope that is designed to detect radio waves rather than light waves.
star A large ball of gases that radiates light. The star nearest the Earth is the Sun.
sUn The star that the planets of the Solar System revolve around.
Universe The entirety of everything there is; the cosmos.
x-ray An invisible form of radiation that has extremely short wavelengths just beyond the ultraviolet.
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