Solar System

The Solar System Solar system Consists of the Sun, 8 planets more than 130 natural satellites & other small bodies Mostly empty space Sun Largest object in our solar system 99.8% of the total mass of our solar system 70 % hydrogen, 28% helium, 2% other metals Nuclear fusion changes hydrogen to helium & energy 150 million km (93 million miles from Earth) 1 AU - astronomical unit Each second about 700,000,000 tons of hydrogen are converted to about 695,000,000 tons of helium and 5,000,000 tons (=3.86e33 ergs) of energy in the form of gamma rays.

The Sun The picture at left shows the sun with a huge solar prominence. Special cameras were used to take the picture. Do not ever view the sun without special eye protection or filters. Staring at the sun can permanently blind your eyes!

We think of the Earth as a huge place. The sun’s interior could hold over 1.3 million Earths! We think of the Earth as a huge place. The diameter of the Sun is about 100 times wider than the Earth as can be seen in the diagram above.

Inner planets Mercury, Venus, Earth, Mars Known as the terrestrial planets Small in size & have solid, rocky surfaces Slow rotation, no rings and few satellites (moons) Asteroid belt Lies between the orbits of Mars & Jupiter Forms boundary between inner & outer planets

Outer planets First four: Jupiter, Saturn, Uranus, Neptune Gas giants or Jovian planets Composed primarily of hydrogen and helium and generally have low densities, rapid rotation, deep atmospheres, rings and lots of satellites.

Pluto – no longer considered a planet Small & rocky like the terrestrial planets Less than 2/3 the size of Earth’s moon Has a single moon, Charon May be a double planet instead of a moon & planet

How significant are we?