Astros

Winny Lallesca Vieira

Main Concepts

Universe................................... 1

Galaxies................................... 2

Solar System........................... 3-5

Planets..................................... 6

Asteroid Belt........................... 7

Earth....................................... 8

Life Cycle of Stars................ 9-10

Parallax.................................. 11

Agricultural Implication......... 12

Universe,the totality of everything that exist, including all matter and energy, the planets, stars, galaxies, and the contents of intergalactic space. Scientific observation of earlier stages in the development of the universe, which can be seen at great distances, suggests that the universe has been governed by the same physical laws and constants throughout most of its extent and history. There are various multiverse theories, in which physicists have suggested that our universe might be one among many universes that likewise exist.

1

Galaxies,is a massive, gravitationally bound system that consists of stars and stellar remnants, an interstellar medium of gas and dust, and an important but poorly understood component tentatively dubbed dark matter. The word galaxy is derived from the Greek galaxies (γαλαξίας), literally "milky", a reference to the Milky Way galaxy. Examples of galaxies range from dwarfs with as few as ten million stars to giants with a hundred trillion stars, each orbiting their galaxy's own center of mass.

Comparing galaxies:
|Galaxies |Size |Number of stars |
|Spiral |angular size is over 4 arcmin, |Between 200 and 400 billion stars|
| |corresponding to to a diameter of | |
| |about 200,000 light-years. |