Across
- 4. The lunar maria /ˈmɑːriə/ (singular: mare /ˈmɑːreɪ/) are large, dark, basaltic plains on Earth's Moon, formed by ancient volcanic eruptions. They were dubbed maria, Latin for "seas", by early astronomers who mistook them for actual seas.
- 5. he force that attracts a body toward the center of the earth, or toward any other physical body having mass.
- 8. a celestial body moving in an elliptical orbit around a star
- 9. a chart or series of pages showing the days, weeks, and months of a particular year, or giving particular seasonal information.
- 10. a large, bowl-shaped cavity in the ground or on the surface of a planet or the moon, typically one caused by an explosion or the impact of a meteorite or other celestial body.
- 12. A lunar eclipse occurs when the Moon passes directly behind Earth and into its shadow. This can occur only when the Sun, Earth, and Moon are exactly or very closely aligned (in syzygy), with Earth between the other two.
- 16. either of the two times in the year, the summer solstice and the winter solstice, when the sun reaches its highest or lowest point in the sky at noon, marked by the longest and shortest days.
- 18. the total or partial obscuring of one celestial body by another. A solar eclipse occurs when the moon passes between the sun and the earth; a lunar eclipse when the earth passes between the sun and the moon See also total eclipse, partial eclipse, annular eclipse Compare occultation.
- 20. the action of rotating around an axis or center.revolution
- 21. A tide in which the difference between high and low tide is the least. Neap tides occur twice a month when the Sun and Moon are at right angles to the Earth. When this is the case, their total gravitational pull on the Earth's water is weakened because it comes from two different directions.
- 23. each of the aspects of the moon or a planet, according to the amount of its illumination, especially the new moon, the first quarter, the full moon, and the last quarter.
- 24. a fixed luminous point in the night sky which is a large, remote incandescent body like the sun.
Down
- 1. the fully shaded inner region of a shadow cast by an opaque object, especially the area on the earth or moon experiencing the total phase of an eclipse.
- 2. a law stating that any two masses attract each other with a force equal to a constant (constant of gravitation) multiplied by the product of the two masses and divided by the square of the distance between them.
- 3. small body of matter from outer space that enters the earth's atmosphere, becoming incandescent as a result of friction and appearing as a streak of light.
- 6. an artificial body placed in orbit around the earth or moon or another planet in order to collect information or for communication.
- 7. a tide just after a new or full moon, when there is the greatest difference between high and low water.
- 11. he time or date (twice each year) at which the sun crosses the celestial equator, when day and night are of equal length (about September 22 and March 20).
- 13. a forcible overthrow of a government or social order, in favor of a new system.
- 14. a small body moving in the solar system that would become a meteor if it entered the earth's atmosphere.
- 15. The definition of tide is the cycle of rising and falling of the surface of bodies of water caused by the attraction of the moon and the sun. An example of the tide is when the ocean's water is at its highest point on the beach.
- 17. a celestial object consisting of a nucleus of ice and dust and, when near the sun, a “tail” of gas and dust particles pointing away from the sun.
- 19. The definition of a penumbra is the lighted area around the shadow of a planet or moon during an eclipse.
- 22. 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.