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ACTIVITY #1 : JUMBLED WORD VISUAL CLUE ANSWER AGR LARGE EL ASG GAS ACTIVITY #1 : JUMBLED WORD VISUAL CLUE ANSWER ARS STARS TS SUDT DUST LODUSC CL...

ACTIVITY #1 : JUMBLED WORD VISUAL CLUE ANSWER AGR LARGE EL ASG GAS ACTIVITY #1 : JUMBLED WORD VISUAL CLUE ANSWER ARS STARS TS SUDT DUST LODUSC CLOUDS ACTIVITY #1 : JUMBLED WORD VISUAL CLUE ANSWER SPLTANE PLANETS L XG A A Y GALAXY Different Theories on the Origin of the Universe SCIENTIFIC THOUGHTS: Steady State Theory Planetesimal Hypotheses Tidal Theory  Life Cycle of a Star A STAR IS BORN – STAGES COMMON TO ALL STARS All stars start as a nebula. A nebula is a large cloud of gas and dust. Gravity can pull some of the gas and dust in a nebula together. The contracting cloud is then called a protostar. A protostar is the earliest stage of a star’s life. A star is born when the gas and dust from a nebula become so hot that nuclear fusion starts. Once a star has “turned on” it is known as a main sequence star. When a main sequence star begins to run out of hydrogen fuel, the star becomes a red giant o red super giant. THE DEATH OF A LOW OR MEDIUM MASS STAR After a low or medium mass or star has become a red giant the outer parts grow bigger and drift into space, forming a cloud of gas called a planetary nebula. The blue-white hot core of the star that is left behind cools and becomes a white dwarf. The white dwarf eventually runs out of fuel and dies as a black dwarf. THE DEATH OF A HIGH MASS STAR A dying red super giant star can suddenly explode. The explosion is called a supernova. After the star explodes, some of the materials from the star are left behind. This material may form a neutron star. Neutron stars are the remains of high-mass stars. The most massive stars become black holes when they die. After a large mass star explodes, a large amount of mass may remain. The gravity of the mass is so strong that gas is pulled inward, pulling more gas into a smaller and smaller space. Eventually, the gravity becomes so strong that nothing can escape, not even light. References Earth Science Book ( C and E Publishing )