Sun and 9 planets

Here are the planets listed in order of their distance from the Sun:

Sun and 9 planets

Then, on October 6,Michel Mayor and Didier Queloz of the Geneva Observatory announced the first definitive detection of an exoplanet orbiting an ordinary main-sequence star 51 Pegasi.

Many known extrasolar planets are many times the mass of Jupiter, approaching that of stellar objects known as brown dwarfs. Brown dwarfs are generally considered stars due to their ability to fuse deuteriuma heavier isotope of hydrogen.

Although objects more massive than 75 times that of Jupiter fuse hydrogen, objects of only 13 Jupiter masses can fuse deuterium. Deuterium is quite rare, and most brown dwarfs would have ceased fusing deuterium long before their discovery, making them effectively indistinguishable from supermassive planets.

There were particular disagreements over whether an object should be considered a planet if it was part of a distinct population such as a beltor if it was large enough to generate energy by the thermonuclear fusion of deuterium. A growing number of astronomers argued for Pluto to be declassified as a planet, because many similar objects approaching its size had been found in the same region of the Solar System the Kuiper belt during the s and early s.

Pluto was found to be just one small body in a population of thousands. Some of them, such as QuaoarSednaand Eriswere heralded in the popular press as the tenth planetfailing to receive widespread scientific recognition.

Acknowledging the problem, the IAU set about creating the definition of planetand produced one in August The number of planets dropped to the eight significantly larger bodies that had cleared their orbit Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptuneand a new class of dwarf planets was created, initially containing three objects CeresPluto and Eris.

The positions statement incorporates the following guidelines, mostly focused upon the boundary between planets and brown dwarfs: The minimum mass and size required for an extrasolar object to be considered a planet should be the same as that used in the Solar System.

Substellar objects with true masses above the limiting mass for thermonuclear fusion of deuterium are " brown dwarfs ", no matter how they formed or where they are located. Free-floating objects in young star clusters with masses below the limiting mass for thermonuclear fusion of deuterium are not "planets", but are "sub-brown dwarfs" or whatever name is most appropriate.

This working definition has since been widely used by astronomers when publishing discoveries of exoplanets in academic journals. It does not address the dispute over the lower mass limit, [50] and so it steered clear of the controversy regarding objects within the Solar System.

This definition also makes no comment on the planetary status of objects orbiting brown dwarfs, such as 2Mb. One definition of a sub-brown dwarf is a planet-mass object that formed through cloud collapse rather than accretion. This formation distinction between a sub-brown dwarf and a planet is not universally agreed upon; astronomers are divided into two camps as whether to consider the formation process of a planet as part of its division in classification.

For example, a planet formed by accretion around a star may get ejected from the system to become free-floating, and likewise a sub-brown dwarf that formed on its own in a star cluster through cloud collapse may get captured into orbit around a star.


The 13 Jupiter-mass cutoff represents an average mass rather than a precise threshold value. Large objects will fuse most of their deuterium and smaller ones will fuse only a little, and the 13 MJ value is somewhere in between. After much debate and one failed proposal, a large majority of those remaining at the meeting voted to pass a resolution.

The resolution defines planets within the Solar System as follows: Under this definition, the Solar System is considered to have eight planets. Bodies that fulfill the first two conditions but not the third such as Ceres, Pluto, and Eris are classified as dwarf planetsprovided they are not also natural satellites of other planets.

Originally an IAU committee had proposed a definition that would have included a much larger number of planets as it did not include c as a criterion. As described by astronomer Steven Soter: Minor planets and comets, including KBOs [Kuiper belt objects], differ from planets in that they can collide with each other and with planets.

Astronomer Jean-Luc Margot proposed a mathematical criterion that determines whether an object can clear its orbit during the lifetime of its host star, based on the mass of the planet, its semimajor axis, and the mass of its host star.The Solar System is the gravitationally bound system of the planets and the Sun plus other objects that orbit it, either directly or indirectly.

Of the objects that orbit the Sun directly, the largest eight are the planets, with the remainder being smaller objects, such as dwarf planets and small Solar System bodies.

Sun and 9 planets

An Introduction In our solar system, nine planets circle around our Sun sits in the middle while the planets travel in circular paths (called orbits) around nine planets travel in the same direction (counter- clockwise looking down from the Sun's north pole).

The names of the nine planets in order are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Many individuals use a mnemonic, or memory device, to remember these names.

Pluto used to be considered a planet but is no longer classified as one. The International Astronomical Union.

The Sun - Universe Today

Information, portal, Indian Astrologer, Astrology, Vedic Indian Astrology, Numerology, Kundali Matching, Tarot Reading, Vaastu Shastra, Fengshui, Hindu marriage. Planets in astrology have a meaning different from the modern astronomical understanding of what a planet the age of telescopes, the night sky was thought to consist of two very similar components: fixed stars, which remained motionless in relation to each other, and "wandering stars" (Ancient Greek: ἀστέρες πλανῆται asteres planetai), which moved relative to the.

Astronomers have detected what may be four roughly Earth-size planets orbiting Tau Ceti, the nearest sun-like star. Two of the worlds appear to orbit within Tau Ceti's habitable zone, though a.

☀ The Sun - Educational facts and history of the star we call The Sun.