17 June 2009

celestial bodies

1. Asteroids

  • also called minor planets or planetoids, they are small sized celestial bodies (smaller than planets but larger than meteoroids) in orbit around the sun.
  • the difference between asteroids and comets can been seen by visual appearance where comets show a clear coma (tail) though asteroids do not.

2. Moons

  • also known as natural satelites, moons are calestial bodies that orbit a planet (the primary)
  • up to september 2008,335 bodies have been classified as moons, including 167 moons orbiting six of the eight main planet in our solar system.
  • about six moons, the four jupiter Galilean moons, Saturn's Titan, and Neptune's Triton, are also quite similar in size to Earth.

3. Planets

  • a celestial body orbiting a star.
  • planet is an ancient term that intertwines with science, myth, and religion.
  • generally, planets are divided into two groups, either large, low-density gas giants or smaller, rocky terrestrial planets.
  • of the eight planets in our solar system, four our rocky terrestrial (Mercury, Venus, Earth and Mars) and the other four our gas giants (Jupiter, Saturn, Uranus, and Neptune)
  • furthermore, there are also five dwarf planets orbiting our sun, named Ceres, Pluto, Makemake, Haumea and Eris.

4. Stars (sun)

  • a massive, bright ball of flames (plasma), held together by gravity.
  • our sun is the nearest star to Earth and is also the source of most of our energy.
  • other suns can be seen as stars at night light from thermonuclear fusion in the core releases an abundance of energy into space.
  • the fusion process in stars also produces all other elements heavier than hydrogen and helium.
  • a star system can also consist of twin stars (or more) that orbit each other
  • a star can also age and burn up its 'fuel'.
  • a dying star can collapse on its own gravity, thus forming a black hole in its place, or explode causing a supernova that triggers the formation of new stars.

5. Galaxies

  • a massive, gravitationally bound system consisting of stars, astral bodies, gas and dust
  • it also contains an important but poorly-understood component, dubbed as dark matter (accounting about 90 percent of the galaxy mass)
  • can range from giants (with trillions of stars) to dwarfs containing only a few million
  • the galaxy systems can contain several solar systems or just clusters of stars and various interstellar clouds
  • there can also be multiple vshapes of galaxies, elliptical, spiral (disk-shaped), or irregularly shaped due to the disruption (gravitationalpull) of neighboring galaxies.
  • it's estimated that there are over 100 billion galaxies in our universe
  • it's also believed thay many (or all) galaxies (including ours) have one or more supermassive black holes in its centre.

4 comments:

mizie's life said...

waahhh...da start ader info dalam blog ney yaa...gewdd2..

LaiLa isabeLLa said...

tq..

mizie's life said...

bler nk tambah info yang laen...?

LaiLa isabeLLa said...

tgh cari bhan ler ni..wait n see k.