Exodwarf planet

ExoDwarf planet is a term that arose as a result of the creation in 2006 of the term dwarf planet by the International Astronomical Union (IAU). While the term dwarf planet is only for our solar system there was sufficient confusion about the results of the IAU planet definition debate and resolutions that the term came to be used for outside the solar system by some in the general public.
An exodwarf planet like a dwarf planet in our solar system must orbit a star. So far we have objects that meet the criteria of an exodwarf planet in terms of mass but in terms of what they orbit they can be considered exodwarf planets if we consider stellar remnants stars which is a controversial idea.
Astrophysicist David Jeffery writes on his website:"There are, of course, unlimited exo-dwarf planets to discover. (See ExoDwarf for more on exo-dwarf planets.) But they are small and our exoplanet discovery techniques strongly favor large exoplanets. At present, it seems there is only one candidate exo-dwarf planet called which is orbiting pulsar PSR B1257+12. It would be a dwarf pulsar planet. Pulsar planets may form from the supernova explosion that creates a pulsar and not be the from original planet formation around the original star."
There was however before an object that could also be an exodwarf planetary candidate. A sun-like star towards the end of its life swells to form a red giant. Eventually after giving off its outer layers it leaves behind a hot core of carbon and oxygen called a white dwarf. An international team of astronomers examining thousands of white dwarfs for unusual chemical compositions used the MMT Observatory in Arizona for one outstanding target about 440 light-years away in the direction of the constellation Gemini.
This white dwarf has heavy chemical elements like silicon, magnesium, calcium, and iron. Because a white dwarf’s gravity is 100 thousand times that of Earth’s these heavy elements should sink below the surface. Since we can see them the source must be from outside the star, from a rocky planet torn apart by tidal forces with the debris forming a disk around the white dwarf that is raining onto the star’s surface. Observations from the Gemini Observatory in Hawaii detected this debris disk.
Judging from the amount of material on the white dwarf and surrounding it the destroyed planet was about the size of Ceres, the largest asteroid and a dwarf planet in our solar system.
“There are now more than 450 extrasolar planets known, all of them bigger than Earth, and we don’t really know much about their compositions. Here we’re seeing the remnants of an extrasolar dwarf planet, which gives us a chance to learn about the chemistry of worlds in distant planetary systems,” said Mukremin Kilic of the Smithsonian Astrophysical Observatory.
“White dwarf science is telling us that there are many small planets similar to those in our solar system out there. Since it is not possible to detect such small objects in orbit around other stars with our current technology, studies such as this one offer a unique opportunity to learn about other planetary systems,” added lead author Patrick Dufour of the University of Montreal.
PSR B1257+12 D which orbits the pulsar PSR B1257+12 is a dwarf pulsar planet with less than 20% of Pluto's mass. It is a comet whose coma is causing a signal at 430 MHz.

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