Isaac newton showed that an elliptical orbit like the one described in Kepler's laws is produced when the gravitational force is an inverse-square law, in other words if the distance doubles, the force goes to a quarter. He did this by producing the law of gravity, the laws of motion, and the differential calculus, and these are covered in school-level mathematics.
Planets remain almost perfectly spherical as they move around the sun. The paths they follow are ellipses, with the sun at one focus of each ellipse.
It is Kepler's first law which says the planet moves in an ellipse with the Sun occupying one focus and the other focus is vacant.
Kepler
Isaac Newton showed that an elliptical orbit like the one described in Kepler's laws is produced when the gravitational force is an inverse-square law, in other words if the distance doubles, the force goes to a quarter. He did this by producing the law of gravity, the laws of motion, and the differential calculus, and these are covered in school-level mathematics.
Planetary orbits are usually in the shape of an ellipse.
To be in a perfect orbit around the Sun, maintaining always the same distance, at a specific distance a planet would need a very specific speed. Since it is unlikely that it just happens to have the correct speed, it will move around the Sun in an ellipse instead.
The Sun's gravity causes a planet to move in its orbit. The Sun's gravity provides a centripetal force. The effects of the Sun's gravity, combined with the planet's inertia (tendency to move in a straight line), results in a planet's elliptical orbit.
The person who first stated this was Johannes Kepler.
no you can not move around on Jupiter because it is a gas planet.
neptune
it's gravity
That is one of Kepler's Laws, stated by Johannes Kepler.