All about the universe.

YEAR 9 SETI ASSIGNMENT OBJECTS IN THE UNIVERSE i.Explain how stars washstand be classified accord to size, colour and temperature. Astronomers use The Hertzsprung-Russell Diagram, which is a graphical tool to sort stars according to their luminosity, spectral type, color, temperature and evolutionary stage. In this diagram, the brightest stars rest nigh(a) the top of the diagram and the hottest stars lie to the go away. On the H-R diagram, most of the stars, including the Sun, authorize along a prejudice run that goes from the upper left to the lower right of the diagram. This line is called the primary(prenominal) episode. The great bulk of stars asolelyting the Sun origin on the lower start out of the H-R diagrams master(prenominal) sequence, and relatively few lie on the piece of the main sequence above the Sun. This means that most of the Suns neighboring stars ar some(prenominal) cooler and fainter (in absolute magnitude) than the Sun. A littler population of brighter but cooler stars known as supergiants occupies the topmost region of the diagram. some(a) stars, which argon difficult to disc everyplace because they are so faint, lie near the bottom of the H-R diagram. These faint stars are called white dwarfs. below is the Diagram of Main Sequence. ii.Explain what a galaxy is and describe, with examples, the four main types.

A galaxy is a collection of billions of stars and bet held by and large together by gravity. They are often dot over thousands of light years. Astronomers estimate that there are or so 125 billion galaxies in the universe. All the stars vi sible to the unbacked eye from Earth belon! g to Earths galaxy, the Milky Way. The Sun, with its associated planets, is just ace star in this galaxy. There are four main types of galaxies: Spiral Galaxies: a galaxy consisting of an... If you want to get a full essay, coif it on our website: BestEssayCheap.com

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