Astronomy #7
Order by
47 terms
Terms | Definitions |
|---|---|
 day | the period of time taken by a particular planet (e.g. Earth or Mars) to make a complete rotation on its axis |
| orbit | the path of one celestial body (ie. planet or moon) in its revolution about another |
| planet | a large "body" that revolves around a star |
| star | a celestial body of hot gases that radiates energy and light |
| axis | an imaginary line that passes through Earth's center and its North and South Poles |
| year | the period of time that it takes for a planet to make a complete revolution around its star |
| axial tilt | the angle at which a planet's axis tilts |
| horizon | the line at which the sky and earth appear to meet |
| solar system | the group of objects consisting of the Sun and all the bodies that orbit it |
| sun | name for the star at the center of our solar system |
| sunrise | the time when the uppermost portion of the Sun's disk appears above the horizon |
| sunset | the time when the uppermost portion of the Sun's disk disappears below the horizon |
| revolution | the act of moving in an orbit around another object |
| rotation | the act of spinning on an axis |
| clockwise | in the same direction as the rotating hands of a clock |
| time zone | one of the standard areas into which the earth is divided; they correspond to the 24 hours in a day |
| international date line | the imaginary line passing through the western Pacific ocean that marks the start of a new day. |
| moon | a natural satellite that orbits a planet |
| galaxy | a collection of solar systems held together by gravity |
| universe | all of space and everything in it (made up of galaxies) |
| natural satellite | orbiting objects that are not man-made |
| artificial satellite | man-made equipment that orbits around the earth or the moon |
| direct sunlight | sunlight that reaches the surface of the earth of angles greater than 45° |
| indirect sunlight | sunlight that reaches the surface of the earth of angles less than 45° |
| season | a change in climate caused by a change in the amount of solar energy due to the axial tilt of the earth as it revolves around the sun |
| equinox | the time when day and night are of equal length at the equator (spring and fall) |
| solstice | the day when the Sun reaches its greatest distance north or south of the equator (winter and summer) |
| midnight | time when the sun is shining most directly on the meridian on the "other side" of the earth from your current position. |
| noon | time when the sun is shining most directly on your meridian (longitude) |
| waxing | a gradual increase in size |
| waning | a gradual decrease in size |
| crescent | Moon phase that looks like a "sliver" of Moon; during the week before and the week after a New Moon |
| gibbous | Moon phase in which more than half of the Moon appears to be illuminated. Rounded outwards. |
| latitude | an imaginary line around the Earth parallel to the equator measured in degrees |
| longitude | Distance east or west of the prime meridian, measured in degrees |
| lunar eclipse | occurs when Earth's shadow falls on the Moon |
| solar eclipse | Occurs when the Moon passes directly between the Sun and Earth and casts a shadow over part of Earth. |
| partial eclipse | an eclipse in which the eclipsed body is only partially obscured |
| total eclipse | an eclipse as seen from a place where the eclipsed body is completely obscured |
| umbra | the darkest part of a shadow |
| penumbra | partial shadow (not as dark) |
| tide | the rise and fall of the sea level because of the gravitational pull of the moon and sun |
| tidal range | Is the difference in the water level between the high tide and the low tide. |
| spring tide | When the tidal range is greatest. (full moon and new moon) (High high tides and low low tides) |
| neap tide | When the tidal range is lowest. (first quarter moon and last quarter moon) |
| lightyear | the distance that light travels in a year 9, 460, 730, 472, 580.8 km |
| astronomical unit | the average distance between the earth and the sun, about 150,000,000 km |
First Time Here?
Welcome to Quizlet, a fun, free place to study. Try these flashcards, find others to study, or make your own.
Set Champions
Scatter Champion
16.9 secs by SunriseSunset
Space Race Champion
108,330 points by matthewluddzz
Speller Champion
100% correct by mackdaddy911