click below
click below
Normal Size Small Size show me how
Earth and sky terms
Term | Definition |
---|---|
Moon | Earth's only natural satellite |
Planet | Object that orbits the sun |
Number of planets in the solar system | Eight |
Number of planets visible without a telescope | Five |
How objects in the sky appear to move | Depends on the motion of the Earth. |
Meteor | The bright streak of light produced when a small object burns up entering Earth’s atmosphere. |
Comet | A cold mixture of dust and ice that gives up a long trail of light as it approaches the sun. Very rare - Rarer than meteors. |
Stars | Inferred by scientists to be a giant ball of hot gas mainly composed of hydrogen and helium. |
Constellation | A pattern or group of stars that people imagined to represent a figure, animal or object. |
Zodiac | A narrow band in the sky where the planets appear to be. |
Ecliptic | A path the Sun travels in the sky. Planets and the moon follow a similar line. |
Axis | The imaginary line that passes through Earth’s center and the North and South poles. |
Rotation | The spinning of Earth on its axis |
Revolution | The movement of one object around another. |
Orbit | Earth's path |
Calendar | A system of organizing time that defines the beginning, length, and divisions of a year. |
Solstices | The day when the sun appears farthest north of the equator once each year and farthest south once each year. |
Equinox | "equal night”. Halfway between the solstices when neither hemisphere is tilted toward the sun. |
Summer solstice | The day in when the sun appears farthest north. |
Winter solstice | The day when the sun appears farthest south |