Even if the list of planets is officially lengthened when astronomers vote on Aug. Opponents of Pluto, which was named a planet in , still might spoil for a fight. Earth's moon is larger; so is UB Xena , about 70 miles wider. But the IAU said Pluto meets its proposed new definition of a planet: any round object larger than kilometers nearly miles in diameter that orbits the sun and has a mass roughly one,th that of Earth.
Moons and asteroids will make the grade if they meet those basic tests. Roundness is key, experts said, because it indicates an object has enough self-gravity to pull itself into a spherical shape. Yet Earth's moon wouldn't qualify because the two bodies' common center of gravity lies below the surface of the Earth.
But Pluto has gravity on its side. Venus is slightly smaller than Earth and can be seen with the naked eye here on Earth. Surface temperatures can reach degrees celsius , which are the product of a runaway greenhouse effect.
It has a thick atmosphere, about 90 times that of Earth, that is rich in sulfuric acid and carbon dioxide. Mother Earth is the only planet known to be habitable to life. It is also one of the largest terrestrial planets in our solar system.
Conditions are such that water can exist in liquid form. Enough said, we are sure you are more than aware of the characteristics of our home planet, since you live on it. Its most distinguishing feature is its red surface coloration, formed by large amounts of iron oxide. Mars' surface has many large volcanoes and deep valleys, and frequently experiences planet-wide wind storms. Mars is colder than Earth, with temperatures fluctuating between and 0 degrees celsius.
As the largest planet in our solar system, Jupiter is named after the king of the Roman gods. This is the first of the gas giants, and has a characteristic turbulent atmosphere of hydrogen, helium, methane, ammonia and frozen water. The largest and most distinctive of its storms, the "Great Red Spot", is larger than Earth.
Jupiter has 53 named moons and another 26 awaiting official names. Saturn is the 6th planet from the Sun and is another of our solar system's gas giants. By far its most characteristic feature is its set of magnificent rings. Each ring orbits the planet in a thin band roughly 1-mile 1. Saturn is 9. Its atmosphere is similar in composition to Jupiter and at its core pressures are so high that gases may condense to form liquids, and even metals.
A decision and announcement of a new name are likely not to be made during the IAU General Assembly in Prague, but at a later time. The naming procedures depend on the outcome of the Resolution vote. There will most likely be more planets announced by the IAU in the future. Plutons are distinguished from classical planets in that they reside in orbits around the Sun that take longer than years to complete i. Plutons typically have orbits that are highly tilted with respect to the classical planets technically referred to as a large orbital inclination.
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