The orbit of the planets around the sun is a result of two opposing forces that are held in perfect balance. Planetary inertia serves to carry the planets on a course that would send them out of the solar system were it not for the gravitational attraction of the sun.
The solar system was created from a vast cloud of spinning dust and gas. As this spinning cloud began to collapse under the weight of its own gravity, it began to flatten out, forming a disk. The sun, the most massive object within the solar system, formed at the center of this gas cloud. Particles within the outer portions of this accretion disk began to collide, creating larger and larger objects until eventually they formed into the planets of the solar system.
The inertia of the planets is derived from the spinning motion of the accretion disk which formed the solar system. This sideways momentum serves to counteract the pull of the sun's gravity, and without it there would be nothing to keep the planets from falling inward and being consumed by the sun. Without an outside force to counteract their inertia, the planets continue to orbit the sun uninterrupted.Learn More
In 2006, the International Astronomical Union defined a planet as a body that is in orbit around the sun, has enough mass to establish a round shape, and has cleared other debris from the neighborhood of its orbit. This ruling famously resulted in the demotion of Pluto to dwarf planet status, since Pluto did not have the gravitational influence to clear other bodies from its orbital path.Full Answer >
When the Earth makes an orbit around the sun, NASA refers to it as a revolution. It takes Earth 365.25 days to make a complete revolution around the sun.Full Answer >
The planet Mars completes its orbit of the sun in just under 687 Earth days. Mars orbits the sun much further away than Earth, and its longer year results from having to travel a greater distance.Full Answer >
The Earth completes a rotation around the sun, known as an orbit, in 365.24 days. Earth is located an average of 92.96 million miles from the sun, varying between the closest distance of 91.40 million miles and the furthest distance of 94.51 million miles.Full Answer >