Life Cycle of a Star

1. Life Cycle of a Star By: Shawn and James

2. Nebula • A Nebula is an Interstellar cloud of dust. • It is usually made of Hydrogen gas and Plasma. http://upload.wikimedia.org/wikipedia/commons/7/74/Triangulum.nebula.full.jpg

3. Protostar • A large object that forms out of the gas of a giant molecular cloud in the interstellar medium • It is a stage in the star formation. http://upload.wikimedia.org/wikipedia/commons/1/1f/123107main_image_feature_371_ys_4.jpg

4. Brown Dwarf • Brown Dwarfs are bigger and different than planets, but they are not stars. • They don’t have enough mass to burn hydrogen and make nuclear fusion. http://upload.wikimedia.org/wikipedia/commons/9/94/T-dwarf-nasa-hurt.png

5. Main Sequence Star • These are stars are in a distinct band that appear on the Hertzsprung-Russell diagram and other plots of stellar color versus brightness. http://aspire.cosmic-ray.org/labs/star_life/starlife_sequence.html

6. Red Giant • A red giant is a very big star that weighs about ½ to ten times as much as our sun. • They appear to be colored red. • Most red giants could fit thousands of our suns inside of them. http://www.historyoftheuniverse.com/starold.html

7. Planetary Nebula • A nebula made of gas and plasma • They are made by certain types of stars when they die. • They are named because they look like planets through small optical telescopes. • They last only tens of thousands of years. http://upload.wikimedia.org/wikipedia/commons/5/5a/NGC6543.jpg

8. White Dwarf • A star that is not as bright as regular stars. • They are very small but very hot. • They are so hot they give off bright white light. • They take a long time to cool down because they are so small. • They cool down into a black dwarf. http://upload.wikimedia.org/wikipedia/commons/f/f3/Sirius_A_and_B_Hubble_photo.jpg

9. Black Dwarf • A White Dwarf that has cooled down and no longer gives off visible light. • Nobody knows for sure that white dwarfs exist because the amount of time it takes for a White Dwarf to cool is longer than the beginning of the universe. http://www.daviddarling.info/encyclopedia/B/blackdwarf.html

10. High Mass Stars • Instead of turning into a Red Giant, High mass stars turn into Red super giants.

11. Red Supergiant • Red super giants are some of the largest stars in the universe. • They have a diameter of about 1000 times bigger that our sun. http://www.daviddarling.info/encyclopedia/R/redsupergiant.html

12. Supernova • A supernova happens when a very big star explodes • It explodes when the star totally runs out of energy to make heat. http://upload.wikimedia.org/wikipedia/commons/d/d4/Keplers_supernova.jpg

13. Neutron star • It is a very small star made completely of neutrons. • Neutron stars have a radius of about 10 kilometers and a mass of about 1.4 to 5 times of the sun. • They are usually leftovers of massive stars that have exploded as supernovas. http://upload.wikimedia.org/wikipedia/commons/e/ed/Neutron_star_cross_section.jpg

14. Black Hole • A thing in the universe that has such a strong pull of gravity that not even light can escape it. • Until recently, Most astronomers didn’t even know if they existed. • They saw objects being pulled by such a strong force by looking through a telescope. http://electron.cs.uwindsor.ca/~jones11l/img/329px-Black_Hole_Milkyway.jpg

15. Sites • http://simple.wikipedia.org/wiki/Nebula • http://en.wikipedia.org/wiki/Main_sequence • http://en.wikipedia.org/wiki/Helium_fusion • http://simple.wikipedia.org/wiki/Brown_dwarf • http://simple.wikipedia.org/wiki/Black_hole • http://en.wiktionary.org/wiki/black_dwarf • http://en.wikipedia.org/wiki/Black_dwarf