Re: Why does the earth do a circular motion with the sun.
- From: Sam Wormley <swormley1@xxxxxxxxx>
- Date: Wed, 04 Feb 2009 18:29:20 GMT
Ed wrote:
Due to the gravity force between earth and sun, earth and sun should
be closer more and more.
But who make the earth go in circle path.
Same question between Moon and Earth.
Thanks.
The Earth is in an elliptical orbit about the Sun. The are probably
no perfectly circular orbits in the universe.
Part of the answer to your question lies in the formation of the
planets from debris in the solar nebula... And of course conservation
laws apply, such as the
o conservation of momentum
o conservation of angular momentum
o conservation of energy
Johannes Kepler, in more than 900 pages of calculation, over about
four years, attempted to measure the orbit of Mars from Tycho Brahe's
observations...
o from a moving platform
o who's orbit was not centered on the Sun
o rotating on its axis
o of a planet varying in its orbital speed around the Sun.
Kepler's calculations were immensely difficult... but he eventually
realized that an ellipse with an eccentricity of about nine percent
agreed with Tycho Brahe's observational data. Kepler found that the
orbits of planets in our solar system follow ellipses, sweeping out
equal areas in equal times.
Later, Newton discovered (and showed mathematically) that objects in
free fall (such as planets influenced by a central force like the
Sun's gravity) follow the paths of conic sections.
Ref: http://www.projmath.caltech.edu/mu122.htm?10,6
By using his universal law of gravitation and his three laws of motion,
Newton showed why Kepler's three laws are true--That is known as the
solution to the Kepler problem. Its solution is one of the crowning
achievements of Western thought.
A model for Gravitation was essential.
http://scienceworld.wolfram.com/physics/Gravity.html
.
- Follow-Ups:
- Re: Why does the earth do a circular motion with the sun.
- From: Cwatters
- Re: Why does the earth do a circular motion with the sun.
- References:
- Prev by Date: Gross error in Eisberg-Resnick book
- Next by Date: Re: Why does the earth do a circular motion with the sun.
- Previous by thread: Re: Why does the earth do a circular motion with the sun.
- Next by thread: Re: Why does the earth do a circular motion with the sun.
- Index(es):
Relevant Pages
|
