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A dwarf planet, as defined by the International Astronomical Union (IAU), is a celestial body orbiting the Sun that is massive enough to be rounded by its own gravity but has not cleared its neighbouring region of planetesimals and is not a satellite. More explicitly, it has to have sufficient mass to overcome its compressive strength and achieve hydrostatic equilibrium. It should not be confused with a minor planet. The term dwarf planet was adopted in 2006 as part of a three-way categorization of bodies orbiting the Sun, brought about by an increase in discoveries of trans-Neptunian objects that rivaled Pluto in size, and finally precipitated by the discovery of an even larger object, Eris. This classification states that bodies large enough to have cleared the neighbourhood of their orbit are defined as planets, while those that are not massive enough to be rounded by their own gravity are defined as small solar system bodies. Dwarf planets come in between. The definition officially adopted by the IAU in 2006 has been both praised and criticized, and has been disputed by scientists such as Alan Stern. The IAU currently recognizes five dwarf planets—Ceres, Pluto, Haumea, Makemake, and Eris. However, only two of these bodies, Ceres and Pluto, have been observed in enough detail to demonstrate that they fit the definition. Eris has been accepted as a dwarf planet because it is more massive than Pluto. The IAU subsequently decided that unnamed trans-Neptunian objects with an absolute magnitude less than +1 (and hence a mathematically delimited minimum diameter of 838 km) are to be named under the assumption that they are dwarf planets. The only two such objects known at the time, Makemake and Haumea, went through this naming procedure and were declared to be dwarf planets. It is suspected that at least another 40 known objects in the Solar System are dwarf planets, and estimates are that up to 200 dwarf planets may be found when the entire region known as the Kuiper belt is explored, and that the number might be as high as 2,000 when objects scattered outside the Kuiper belt are considered. The classification of bodies in other planetary systems with the characteristics of dwarf planets has not been addressed, although if they were detectable they would not be considered planets. From Wikipedia under the
GNU Free Documentation License How many dwarf planets did Dr. Michael Brown discover? Q. Dr. Michael Brown discovered how many dwarf planets? Asked by katie - Fri Feb 27 15:49:33 2009 - - 1 Answers - 0 Comments A. Of the current official list of 5, technically only 2: Eris and Makemake. His team also had data on Haumea but the discovery is credited to a Spanish team who were the first to submit data to the Minor Planet Center. The situation is a rather acrimonious one as there seems to be evidence that the Spanish team used publicly available information on the pointing history of Brown's telescope to help them. Although the Spanish team has the discovery credit, both teams were invited to submit naming suggestions and the name adopted (Haumea) is that suggested by Brown. Brown was also involved in the discovery of other objects that are yet to be officially recognised as dwarf planets such as: Sedna, Orcus and Quaoar. Answered by Peter T - Fri Feb 27 21:09:16 2009 I have a question about dwarf planets? Q. I looked up the definition for dwarf planet. I understand most of it, except for this part: it does not clear the neighborhood around its orbit. What does that bit mean? Please help. Cheerio! Asked by I <3 Robert Pattinson - Tue Sep 22 18:23:05 2009 - - 8 Answers - 0 Comments A. The gas and dust particles that form the nebulae in which the planet is formed is not absorbed by the planet (due to its low gravity) and so there's a lot of 'debris' in and around said planet's orbit. Answered by L X Q - Tue Sep 22 18:29:20 2009 How many planets have been found and named (including planets, dwarf planets etc.)?
Q. In any solar system Asked by Tiu Y - Wed Sep 23 22:16:54 2009 - - 3 Answers - 0 Comments A. 13 in our solar system... Mercury, Venus, Earth, Mars, Ceres, Jupter, Saturn, Neptune, Uranus, Pluto, Makemake, Haumea, and Eris. There have been 85 extra solar planets confirmed and their masses measured, and there are about 270 planets awaiting confirmation some of which may not actually be planets. Some of these have been given proper names, but most of them are referred to by their star names and a planetary letter (i.e. a, b, c, d... etc). For example the star Gliese 581 has four known planets which are named Gliese 581a, Gliese 581b, Gliese 581c, Gliese 581d. Answered by Brian - Wed Sep 23 22:38:08 2009 From Yahoo Answer Search: "Dwarf Planets"
 news.google.com Centre View Also, what is frequently not mentioned in the hysteria over "carbon footprints" is the fact that natural sources of GHG dwarf those of man. ... and more » news.google.com The Guardian Duties on products from developing countries will probably dwarf present foreign aid to those countries. These funds should be returned to developing ... and more » news.google.com Ahmedabad Mirror If the earth survives then it may live on until the sun becomes a white dwarf incapable of warming anything. But all this is billions of years away. ... and more » From Google News Search: "Dwarf Planets"  georgessecretkey.com 460px x 720px | 33.30kB [source page]  georgessecretkey.com 663px x 720px | 74.90kB [source page]  nightskynation.com 410px x 410px | 30.60kB [source page] Planets Our Solar System Our Solar System is now made up of eight planets and their moons three dwarf planets and moons thousands of asteroids comets and dust particles that orbit From Yahoo Image Search: "Dwarf Planets"  ebook30.com Ebook30.com hu, 03 Dec 2009 03:54:02 GM Publisher Rosen Education Service PDF MB After hundreds of years of observation theorizing exploration and data collection the universe is still a mysterious place Numerous cosmic questions 155418.  experienceproject.com unknown Wed, 06 Jan 2010 18:16:14 GM Official or semi-official, depedning who you want ot believe: 4 Terrestrial Planets (Mercury, Venus, Earth, Mars), 4 Giant Planets (Jupiter, Saturn, Neptune, Uranus), 5 . Dwarf Planets. (Ceres, Pluto, Makemake, Haumea, Eris), ...  laurele.livejournal.com laurele Fri, 18 Dec 2009 06:36:26 GM Alan is a wonderful writer, and really does make a good case for ". dwarf planets. " just being a dynamic sub-category of "planets". One really good point the book makes (page 200): if moons can lurk in planetary rings, why can't planets ... From Google Blog Search: "Dwarf Planets" |
