| A | B |
|---|
| ABSOLUTE MAGNITUDE | ACTUAL AMOUNT OF LIGHT A STAR GIVES OFF |
| . APPARENT MAGNITUDE | MEASURE OF A STAR'S BRIGHTNESS AS IT APPEARS FROM THE EARTH |
| BACKGROUND RADIATION | ENERGY LEFT FROM THE BIG BANG THAT IS SPREAD EVENLY THROUGHOUT THE UNIVERSE |
| BIG BANG THEORY | A THEORY THAT STATES THAT THE UNIVERSE WAS FORMED BY THE EXPLOSION OF VERY DENSE AND HOT MATTER COMPACTED INTO A SMALL AREA |
| BINARY STAR | A PAIR OF STARS THAT REVOLVE AROUND EACH OTHER. |
| BLACK HOLE | CORE OF A SUPERMASSIVE STAR AFTER A SUPERNOVA |
| BLUE SHIFT | A SHIFT THE BLUE END OF THE SPECTRUM OF A STAR MOVING TOWARD THE EARTH |
| CEPHEID VARIABLE | PULSING VARIABLE STAR THAT VARIES IN BRIGHTNESS. |
| CONSTELLATION | GROUP OF STARS THAT FORM A PATTERN |
| DOPPLER EFFECT | APPARENT CHANGE IN THE WAVE LENGTHS OF LIGHT THAT OCCURS WHEN AN OBJECT IS MOVING TOWARD OR AWAY FROM OUR EARTH |
| ECLIPSING BINARY | BINARY STAR SYSTEM IN WHICH ONE STAR BLOCKS OUT THE LIGHT FROM THE COMPANION STAR. |
| ELLIPTICAL GALAXY | TYPE OF GALAXY THAT CAN VARY IN SHAPE FROM NEARLY SPHERICAL TO A FLAT DISK. |
| . GALAXY: | HUGE COLLECTION OF STARS |
| GIANT STAR | : STAR WITH A DIAMETER 10 TO 100 TIMES THAT OF THE SUN |
| GLOBULAR CLUSTER | GROUP OF STARS IN A SPHERICAL SHAPE |
| GRAVITY | FORCE OF ATTRACTION BETWEEN OBJECTS |
| HERTZSPRUNG-RUSSELL DIAGRAM | CHART OF THE RELATIONSHIP BETWEEN THE ABSOLUTE MAGNITUDE AND THE SURFACE TEMPERATURE OF STARS. |
| IRREGULAR GALAXY | TYPE OF GALAXY WITH NO DEFINITE SHAPE. |
| MAIN SEQUENCE STAR | : STAR LOCATED IN THE AREA THAT RUNS DIAGONAL THROUGH THE H.R. DIAGRAM |
| MILKY WAY GALAXY | GALAXY IN WHICH THE EARTH'S SOLAR SYSTEM IS LOCATED. |
| NEBULAR THEORY | THEORY THAT STATES THAT THE SOLAR SYSTEM BEGAN AS A HUGE CLOUD OF DUST AND GAS CALLED A NEBULA |
| NEUTRON STAR | SMALLEST TYPE OF STAR THAT RESULTS FROM THE SUPERNOVA OF A MASSIVE STAR. |
| NOVA | STAR THAT SUDDENLY GREATLY INCREASED IN BRIGHTNESS AND SOON AFTER SLOWLY BECOMES DIMMER. |
| NUCLEAR FUSION | PROCESS IN WHICH HYDROGEN ATOMS ARE FUSED TO FORM HELIUM ATOMS |
| MAGNITUDE | MEASURE OF A STAR'S BRIGHTNESS |
| OPEN CLUSTER | LARGE, LOOSELY ORGANIZED GROUP OF STARS |
| PARALLAX | APPARENT CHANGE IN THE POSITION OF A STAR IN THE SKY DUE TO THE CHANGE IN THE EARTH'S POSITION AS IT MOVES AROUND THE SUN |
| POLARIS | THE NORTH STAR |
| PRISM | GLASS THAT BENDS LIGHT INTO A SPECTRUM |
| PROTOSTAR | NEW STAR |
| PULSAR | NEUTRON STAR THAT GIVES OFF PULSEDS OF RADIO WAVES |
| QUASAR | QUASI-STELLAR RADIO SOURCE; STARLIKE OBJECT THAT GIVES OFF RADIO WAVES |
| RED SHIFT | SHIFT TOWARD THE RED END OF THE SPECTRUM OF A STAR MOVING AWAY FROM THE EARTH |
| SPECTROSCOPE | INSTRUMENT THAT BREAKS UP THE LIGHT FROM A STAR INTO ITS CHARACTERISTIC COLORS |
| SPECTRUM | BAND OF COLORS FORMED WHEN LIGHT PASSES THROUGH A PRISM |
| SPIRAL GALAXY | TYPE OF GALAXY THAT IS MADE OF A THICK MASS OF MATERIAL AND FLATTENED ARMS THAT SPIRAL AROUND THE CENTER |
| SUPERGIANT STAR | STAR WITH A DIAMETER UP TO 1000 TIMES THAT OF THE SUN |
| SUPERNOVA | EXPLOSION IN WHICH A STAR BREADS APART, RELEASING ENERGY. |
| VARIABLE STAR | STARS WITH A BRIGHTNESS THAT VARIES |
| WHITE DWARF | SMALL, VERY DENSE STAR |
