Question | Answer |
Rotation | the action of rotating around an axis or center. |
Revolution | the movement of an object in a circular or elliptical course around another or about an axis or center. |
Orbit | the curved path of a celestial object or spacecraft around a star, planet, or moon, especially a periodic elliptical revolution. |
Axis | an imaginary line about which a body rotates. |
Solstice | either of the two times a year when the sun is at its greatest distance from the celestial equator |
Equinox | the time or date (twice each year) at which the sun crosses the celestial equator, when day and night are of equal length |
Gravity | the force of attraction by which terrestrial bodies tend to fall toward the center of the earth. |
Law of Universal Gravitation | states that a particle attracts every other particle in the universe using a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. |
Inertia | a property of matter by which it continues in its existing state of rest or uniform motion in a straight line, unless that state is changed by an external force. |
Newton's First Law | states that an object at rest will stay at rest and an object in motion will stay in motion with the same speed and direction unless acted upon by unbalanced force. |
Eclipse | an obscuring of the light from one celestial body by the passage of another between it and the observer or between it and its source of illumination. |
Umbra | The very darkest part of the shadow |
Penumbra | The larger part of the shadow |
Lunar Eclipse | When the Earth is in front of the moon |
Solar Eclipse | When the moon is in front of the Earth |
Tides | The rise and fall of ocean water that occurs every 12.5 hours |
John Glenn | The first Astronaut to orbit the Earth |
Geosynchronous Orbit | A circular orbit around the Earth having a period of 24 hours |
Force | A push or pull |
Maria | Are large, dark, basaltic plains on Earth's Moon, formed by ancient volcanic eruptions. |
Escaping Velocity | The velocity of an object to get out of a gravitational pull |