In 2006, and after much debate, the International Astronomical Union came up with a new definition for a planet. And for the first time, the term "dwarf planet" was used.
Today, astronomers are debating how to define an exoplanet, which is a planet orbiting a star that is not the Sun. Since 1992, thousands of exoplanets have been discovered. Some of these are so big that astronomers are unsure whether they are planets or brown dwarves. A brown dwarf is a...
Pluto is the most well-known dwarf planet of the Kuiper Belt, which lies beyond Neptune. It was discovered on February 18,1930, and was classified as a planet for 76 years. The icy planet has 5 known moons—Charon, Nix, Styx, Kerberos, and Hydra. Pluto is 1,400 miles (2,380 km) ...
A dwarf planet is a small planet that fails the third test. The asteroid Ceres, in orbit around the Sun between Mars and Jupiter, was upgraded from asteroid to dwarf planet status. Clearing the neighbourhood means that it does not cross other planets or asteroids in its wake, which as ...
Vesta recently snatched the "largest asteroid title" from Ceres, whichNASA now classifiesas a dwarf planet.Ceresis the largest object in the main asteroid belt while Vesta is the second largest. As well as coming in a range of sizes, asteroids come in a variety of shapes from near spheres...
Which is the biggest planet in the Solar System? It’s Jupiter! Credit: NASA Ever since the invention of the telescope four hundred years ago, astronomers have been fascinated by the gas giant of Jupiter. Between it's constant, swirling clouds, its many, many moons, and its Giant Red Spo...
This may come as something of a surprise to many watching the drama on Ceres unfold whoguessed that the spots were reflective ice. That's because the dwarf planet is believed to harbor a subsurface ocean that could have been exposed and then frozen by asteroid impacts. ...
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The eight planets of this solar system -- Pluto having been formally demoted by the International Astronomers Union to the status of a dwarf planet -- may be divided into the smaller terrestrial planets of Mercury, Venus, Earth and Mars, and the larger g
Our solar system is located in the Orion arm of the Milky Way galaxy. It has eight planets, each of which orbit the sun at the center of the solar system. Pluto was once thought of as the ninth planet. However, discoveries lead to a change in the definit