Lickszz
30-03-2003, 20:16
ok, about 5 billion years ago Earth was hit by another samller planet the size of Mars. Due to this impact a large peice of Earth exploded off into space. This explains why Earth has a tilted axis. The debris of the planet that hit and Earths own debris obviously formed our moon.
These type of collisions were fairly common during the early development of our Solar System.
The scenario is useful in explaining why certain planets are the way they are today.
For example, the moon is severely lacking in metals. It is mostly composed of rock. The impact theory explains this well. The moon is said to have been formed when the impacting object blasted a large portion of earth's rocky crust into earth orbit.
It also explains why Mercury is almost all metal.
An impact stripped it almost completely of its outer crust leaving mostly the iron metallic core behind.
Another planet that is thought to have been struck is Uranus. Unlike all the other planets, which are mostly tilted at a 30 degree angle, Uranus rolls along at a 98 degree angle with its polar regions facing the sun and its rings pointing up and down instead of sideways as Saturn's do. The impact of a protoplanet ten times as massive as our earth striking one of its poles explains this extreme tilt.
Yet another is Venus,
The sun as well as most of its planets conserve the motion of the original gas and dust cloud from which they were formed. Venus is different. Venus rotates in a retrograde fashion or in the opposite direction-from west to east. So the sun there rises in the West and sets in the East. This is attributed to an impact which completely reversed its rotational direction.
Mars also faced impact.
In this instance the planet's tilt, or incline was changed.
Also, the Martian atmosphere was completely blown into space. This orbital tilt and loss of atmosphere is one explanation given for the severe conditions existing on Mars today.
Pluto's moon, Charon, is also suspected as having been cause by an impact on Pluto.
These type of collisions were fairly common during the early development of our Solar System.
The scenario is useful in explaining why certain planets are the way they are today.
For example, the moon is severely lacking in metals. It is mostly composed of rock. The impact theory explains this well. The moon is said to have been formed when the impacting object blasted a large portion of earth's rocky crust into earth orbit.
It also explains why Mercury is almost all metal.
An impact stripped it almost completely of its outer crust leaving mostly the iron metallic core behind.
Another planet that is thought to have been struck is Uranus. Unlike all the other planets, which are mostly tilted at a 30 degree angle, Uranus rolls along at a 98 degree angle with its polar regions facing the sun and its rings pointing up and down instead of sideways as Saturn's do. The impact of a protoplanet ten times as massive as our earth striking one of its poles explains this extreme tilt.
Yet another is Venus,
The sun as well as most of its planets conserve the motion of the original gas and dust cloud from which they were formed. Venus is different. Venus rotates in a retrograde fashion or in the opposite direction-from west to east. So the sun there rises in the West and sets in the East. This is attributed to an impact which completely reversed its rotational direction.
Mars also faced impact.
In this instance the planet's tilt, or incline was changed.
Also, the Martian atmosphere was completely blown into space. This orbital tilt and loss of atmosphere is one explanation given for the severe conditions existing on Mars today.
Pluto's moon, Charon, is also suspected as having been cause by an impact on Pluto.