Layer of the suns atmosphere found above the photosphere and below the transition zone and corona.
A mass that travels through space and is composed of rock particles and dust mixed with frozen water, methane, and ammonia; tends to vaporize and break up after passing close to the sun many times.
A group of stars that froms a pattern resembling a familiar object, character, or animal, and that changes position thourhout the year because earth moves.
The outermost region of the sun's atmosphere.
The 3rd planet from the sun; its atmosphere protects life and its surface temperatures allow water to exisr as a solid, liquid, and gas.
Arrangement of electromagnetic radiation-including radio waves, visible light from the sun, gamma rays, x rays, ultrviolet waves, ifrared waves, and microwaves-according to their wavelengths.
Elongated, closed curve that describes Earth's yearlong orbit around the Sun.
Either of two times of the year when the sun crosses the plane of the earth's equator and day and night are of equal length.
The time when the moon is fully illuminated.
Large group of stars, dust, and gas held together by gravity; can be elliptical, spiral, or irregular.
Late stage in the life of comparatively low-mass main sequence star in which hydrogen in the core is deleted, the core contracts and temperatures inside the star increase, causing its outer layers to expand and cool.
Great Red Spot
A giant, high-pressure continuous storm on Jupiter.
A hollow left on the surface of the Moon caused by an object striking its surface.
The largest planet and the 5th from the sun.
Light distance travels in one year (9.5 trillion km).
Occurs when Earth's shadow falls on the Moon.
Dark-colored, relatively flat regions of the Moon formed when ancient lava reached the surface and filled craters on the moon's surface.
Fourth planet from the Sun; has polar ice caps, a thin atmosphere, and a reddish appearance caused by iron oxide in weathered rocks and soil.
Planet closest to the Sun; has a thin atmosphere with temperature extremes, an iron core, and many craters and high cliffs.
A meteoroid that burns up in Earth's atmosphere
A meteoroid that does not completely burn up in the atmosphere and strikes the surface of a moon or planet.
Change in appearance of the Moon as viewed from the Earth, due to the relative positions of the Moon, Earth, and Sun.
A large cloud of gas and dust in space, spread out in an immense volume.
Large, gaseous planet with rings, dark-colored storms, and eight moons; has a distinctive blue-green color.
Collapsed core fo a supernova that can shrink to about 20 km in diameter and contains only neutrons in the dense core.
Moon phase that occurs when the Moon is between Earth and the Sun, at which point the Moon cannot be seen because its lighted half is facing the Sun and its dark side faces Earth.
Building that can house an optical telescope; often has a dome-shaped roof that can be opened for viewing.
Curved path followed by Earth as it moves around the Sun.
Lowest layer of the Sun's atmosphere that is also its visible surface, has an average temperature of 5800 K, and is about 400 km thick.
Smallest planet and usually considered to be the ninth planet from the Sun; has a thin atmosphere and a solid, icy-rock surface.
Final stage of the U.S. space program to reach the Moon, with Apollo II landing on the Moon's surface on July 20, 1969.
Early U.S. space program where one Gemini astronaut team connected with another spacecraft in orbit; also studied the effects of space travel on the human body.
First U.S. space program that orbited a piloted spacecraft around Earth and brought it back safely.
An instrument that collects and records radio waves traveling through space and can be used day or night under most weather conditions; provides information to map the universe and look for life on other planets.
An optical magnifying instrument in which light from an object passes through a double convex lens and is bent to form an image at the focal point.
Earth's yearlong elliptical orbit around the sun.
A motor that does not require air to burn either liquid or solid propellant and can carry objects into space.
Spinning of Earth on its imaginary axis, which takes about 24 hours to complete and causes day and night to occur.
Any natural or artificial object that revolves around another object.
Second-largest and sixth planet from the Sun; has a complex ring system, at least 31 moons, and a thick atmosphere made mostly of hydrogen and helium.
Occurs when the Moon passes directly between the Sun and Earth and casts a shadow over part of Earth.
A system made up of the sun, earth, and the other planets and their moons.
Twice-yearly point at which the Sun reaches its greatest distance north or south of the equator.
Instrument that travels far into the solar system and gathers data to send back to Earth.
A reusable spacecraft designed to make many trips and that carries astronauts, satellites, and other cargo to and from space.
A large structure with living quarters, work and exercise areas, and equipment and support systems for humans to live and work in space; can provide the opportunity to conduct research not possible on Earth.
A round, three-dimensional object whose surface is thesame distance from its center at all points; Earth is a sphere that bulges somewhat at the equator and is slightly flattened at the poles.
An area of the Sun that is cooler and not as bright as surrounding areas and that is caused by the Sun's intense magnetic field.
Life cycle stage of a massive star where the core reaches extremely high temperatures, heavy elements form by fusion, and the star expands.
Seventh planet from the Sun; is large and gaseous with thin, dark rings and rotates tilted on its side.
Second planet from the Sun; has a dense atmosphere with high temperatures, a surface with craters, faultlike cracks, and volcanoes; sometimes called Earth's twin.
Describes phases that occur after a full moon, as the visible lighted side of the Moon grows smaller.
Describes phases following a new moon, as more of the Moon's lighted side becomes visible.
Stage in which a star has used up its helium and its outer layers escape into space, leaving behind a hot, dense core that contracts