| A | B |
|---|
| Galaxy | a cluster of stars in the universe |
| Milky Way Galaxy | the galaxy in which we live |
| Constellations | A pattern of stars in the sky |
| Pulsar | A neutron star that produces pulses of radio waves |
| Protostar | the earliest stage of a star's life cycle |
| Hertzsprung-Russell diagram | a diagram that tests for temperature and brightness |
| How long a star lives depends on ... | its mass |
| a light year is a unit of | distance |
| Paralax cannot be used on stars if they are too... | far away |
| Wavelength | the distance between the crest of one wave and the crest of the next one |
| rotation | Earth spinning on its axis (occurs every 24 hours) |
| revolution | when Earth goes around the sun in its orbit (365 days) |
| latitude | the measure from the Earth's equator |
| the moon's orbit is a ___ shape | oval |
| spring tides occur when | the sun, moon and earth all line up |
| maria | regions once flooded by molten lava on the moon |
| Pluto and Charon | are often considered double planets |
| heliocentric | a sun-centered model of the solar system devised by Copernicus |
| meteor | the flash of light produced when a meteroid passes through the Earth's atmosphere |
| solar wind | a stream of particles that are produced by the sun's corona |
| retrograde rotation | the way Venus rotates (opposite that of the Earth's rotation) |
| the Goldilocks Condition | liquid water, appropriate temperature, and a favorable atmosphere |
| asteroid belt | the area between Mars and Jupiter |
| Comet | a chunk of ice and dust with a bright head and a long tail |
| Unbra | the darkest shadow of the moon. |
| Humans first landed on the moon in this year | 1969 |
| vernal equinox | a day in March in which the sun is directly overhead at the equator |
| solar eclipse | when the moon is directly between the Earth and sun |
| the pull of gravity on the surface of the moon is | one sixth that of earth |
| the first person to orbit the earth | Yuri Gagarin |
| nuclear fusion | when a star is born this process takes place |
| a quarsar is a type of ... | galaxy |
| binary star system | a star system containing two or more stars |
| absolute magnitude | a stars true brightness |
| the hottest stars are what color | blue - white |
| inertia | the tendancy of an object to stay in motion or remain at rest |
| geocentric model of the solar system | an Earth centered system of the planets |
| solar flares | explosions on the surface of the sun |
| asteroids | chuncks of rock too numerous and too small to be considered planets |
| eclipsing binary | a star system in which one star blocks the light of another star |
| radio teleoscopes | a teloscope used to detect radio waves from objects in space |
| reflecting teloscope | a teloscope that collects and focuses light using mirrors |
| refracting teloscope | a teloscope that focuses light though a transparent lens |
| nebula | a giant clous of gas and dust in space |
| solstices | June 21 and December 21/22 when the sun is directly overhead at either 23.5 degress north or south latitude |
| penumbra | a partial shadow during an eclipse |
| equinox | March 21 or September 21 when neither hemisphere is tilted towards the sun |
| ellipse | the shape of a planet's orbit |
| sunspots | areas on the sun that are cooler than the surrounding areas |
