Why do venus and uranus spin backwards?
Ail planets in the solar system, including the Earth, spin from west to east. But not Venus and Uranus. This planet, about the same size as the Earth but much closer to the Sun, revolves from east to west, and does so very slowly.
Strangely, its day is longer than its year. Whereas the Earth turns full circle once in twenty four hours, Venus spins once in a little more than 243 of our days. In less than that time.- 225 days it makes a complete trip round the Sun. That orbit is so short because Venus is on average only 108 million km (67 million miles) from the Sun and its orbit is almost circular. Those of other planets are elliptical and therefore longer.
Even though Venus is comparatively close to us, much about it remained a mystery until quite recently. Because it is shrouded in dense cloud, astronomers cannot see and measure its rotation rate by watching it through a telescope. Radar beams, bounced off the planet’s surface, and many space probes have given us data about its rate and direction of spin.
So far, nobody has explained its retrograde rotation. One theory proposed that about 4600 million years ago, when the solar system formed, an accident stopped the infant planet Venus dead in its tracks. A likely event was a collision with another young planet, from which Venus emerged spinning in reverse. But in 1980, mathematicians analysed Venus’s movement, and knocked on the head the notion that its backward spin came from an early collision. Meanwhile, astronomers pore over data from spacecraft and an array of other modern technology in their attempts to find an answer. It remains one of the most puzzling aspects of this most mysterious and inhospitable of planets.
Strangely, its day is longer than its year. Whereas the Earth turns full circle once in twenty four hours, Venus spins once in a little more than 243 of our days. In less than that time.- 225 days it makes a complete trip round the Sun. That orbit is so short because Venus is on average only 108 million km (67 million miles) from the Sun and its orbit is almost circular. Those of other planets are elliptical and therefore longer.
Even though Venus is comparatively close to us, much about it remained a mystery until quite recently. Because it is shrouded in dense cloud, astronomers cannot see and measure its rotation rate by watching it through a telescope. Radar beams, bounced off the planet’s surface, and many space probes have given us data about its rate and direction of spin.
So far, nobody has explained its retrograde rotation. One theory proposed that about 4600 million years ago, when the solar system formed, an accident stopped the infant planet Venus dead in its tracks. A likely event was a collision with another young planet, from which Venus emerged spinning in reverse. But in 1980, mathematicians analysed Venus’s movement, and knocked on the head the notion that its backward spin came from an early collision. Meanwhile, astronomers pore over data from spacecraft and an array of other modern technology in their attempts to find an answer. It remains one of the most puzzling aspects of this most mysterious and inhospitable of planets.
Comments
Post a Comment