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cosmic snowballs of frozen gases, rock and dust that orbit the Sun
What is a comet?
the natural satellite of a planet
What is a moon?
a small rocky body orbiting the sun
What is an asteroid?
a moon, planet or machine that orbits a planet or star
What is a satellite?
a rock that has entered Earth’s orbit
What is a meteor?
the orbit of each planet
What is an ellipse?
the apparent brightness a star would have if it were placed at a standard distance of 10 parsecs from Earth
What is the absolute brightness?
an enormous cloud of dust and gas occupying the space between stars and acting as a nursery for new stars
What is a nebula?
a spot or patch appearing from time to time on the sun's surface, appearing dark by contrast with its surroundings
What is a sunspot?
a sudden flash of increased brightness on the Sun
What is a solar flare?
the movement of a planet around the Sun, a “year”
What is a revolution?
a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter
What is a galaxy?
a celestial body that orbits the sun but has not cleared the neighborhood around its orbit and is not a moon.
What is a dwarf planet?
a celestial body moving in an elliptical orbit around a star
What is a Planet?
the movement or path of the earth or a heavenly body turning on its axis
What is a rotation?
a luminous ball of gas, mostly hydrogen and helium, held together by its own gravity
What is a star?
the range of wavelengths or frequencies over which electromagnetic radiation extends
What is Electromagnetic Spectrum?
the date (twice each year) at which the sun crosses the celestial equator, when day and night are of approximately equal length
What is an equinox?
an eclipse in which the moon appears darkened as it passes into the earth's shadow
What is a lunar eclipse?
an eclipse in which the sun is blocked by the moon
What is a solar eclipse?
a large, bright, gaseous feature extending outward from the Sun's surface, often in a loop shape
What is a prominence?
an event occurring when the Sun appears to reach its most northerly or southerly point in the sky
What is a solstice?
a chart or a graph that shows the intensity of light being emitted over a range of energies
What is a spectrum?
a graph used to classify stars based off of magnitude and temperature
What is an H-R Diaphragm?
the distance that light travels in one year, which is 9.4607 × 1012 km (nearly 6 trillion miles)
What is a light-year?