Why are all of the planets in the solar system and all of the stars in the galaxy on the same plane?

Answer 1

The planets in our solar system are close to being on the same plane, but that plane is not the same as that for the galaxy. Nor is it the same for systems of planets around other stars.

Answer 2

All of the planets in the solar system (that's true now since Pluto is no longer officially a planet) are close to being on the same plane because they all formed out of the disc of material accreted by the sun as it was forming. Rotation about the sun and gravitation flatten this material into a disc, whose thickness is thousands of times smaller than its diameter.

But the plane of the solar system is NOT aligned with the plane of the galaxy -- this should be clear to you on any dark summer night, when you'll see the Milky Way extending very nearly north-south with respect to the earth, while the plane of the eclicptic is very nearly east-west. While it's true most of the stars in the galaxy are in the same plane in the Milky Way (though the thickness of that plane is much more than the thickness of the plane of our solar system), and for the same reason as solar system formation, solar systems themsleves are very randomly aligned with respect to the galactic plane. Ours is way off :)
Solar system alignment all depends on the initial spin of the gas that begins to form the central star, which isn't necessarily aligned with the plane of the galaxy.

Answer 3

The orbits of the planets are all more or less in the same plane (called the ecliptic and defined by the plane of the Earth's orbit). The ecliptic is inclined only 7 degrees from the plane of the Sun's equator.
The Milky Way's main disk stretches across roughly 100,000 light-years of space. Most of the galaxy's tens of billions of stars reside within this relatively thin disk and a thicker bulge near the center. Our solar system sits about 30,000 light-years from the middle. In widely separated patches of sky, the researchers found stars beyond the main disk but along the same plane.
Both of these are attributed due to gravitational spin.
One interesting side note is that the ecliptic of the solar system isn't the same angle as the ecliptic plane of the galaxy .

Answer 4

All eight planets in the solar system are basically in the same plane because when they formed, they formed out of the debris that was left over when the sun formed. I do not know if all the stars in the galaxy are in the same plane. Probably not.

Answer 5

They aren't exactly, it is just easier to represent them that way. in some galaxies and for most of the solar system most things are very near the same plane, for the same reason that cars travel in the same direction on the highway. All those that don't, eventually run into those that do.

If a hypothetical planet happened to rotate 90 degrees to the rest of the planets, the other planets would push it out of orbit a bit twice each time it rotated around the sun, eventually it would crash into the sun, crash into a planet, or go off into open space.

Something like that must have happened to the planet Uranus because it is tilted 90degrees to its orbit.

Answer 6

When a gaseous or particles cloud rotates it will take the aspect of a disc because of the centrifugal force and the attraction towards a center, in our case the Sun.
Both our solar system and our entire galaxy, the Milky Way, are basically flattened and rotating around a center.
The Milky Way is not really a disc, is a spiral galaxy and our Sun is close to the tip of one of the branches.
The spiral shape is one of the most common, but there are galaxies with different shapes: spherical, lenticular, etc.

Answer 7

Well its a very complicated process that I am not going to explain on here because it would take to long to explain on here. The process that creates a sun and planets causes the planets to circle the sun on a plane. The reason pluto does not orbit the sun on a plane is because they think pluto came from the cyper belt and got sucked in by the suns gravity. The stars in a galaxy however are not on a plane. Galaxys come in 3 different shapes.

Answer 8

They're not:
# Solar system includes

* Sun
* Nine planets and their satellites
* Asteroids
* Comets
* Meteoroids

# A planet's orbit lies in an orbital plane

* Similar to a flat sheet of paper
* The orbital planes of the planets are inclined
o Planes of seven planets lie within 3 degrees of the Sun's equator
o Mercury's is inclined 7 degrees
o Pluto's is inclined 17 degrees

# Two groups of planets occur in the solar system

* Terrestrial (Earth-like) planets
o Mercury through Mars
o Small, dense, rocky
o Low escape velocities
* Jovian (Jupiter-like) planets
o Jupiter through Neptune
+ Large, low density, gaseous
+ Massive
+ Thick atmospheres composed of hydrogen, helium, methane, and ammonia
+ High escape velocities

* Pluto not included in either group

Answer 9

What about Pluto? Or did that one get voted of the list of real planets as of late?
Most planets are approximately on the same plane. But this is not true for all solar systems.
http://en.wikipedia.org/wiki/Inclination

Answer 10

They aren't exactly on the same plane. It appears that they are because solar systems and galaxies form from protoplanetary or accretion disks. See the links below for more information.