Van Maanen's Star is a white dwarf star in the constellation Pisces that lies nearly on the ecliptic. It is very dim (mag 12.4) with no nearby bright stars to serve as guideposts. The closest naked-eye star is Delta Piscium at mag 4.4. It's distance of 14.1 light years makes it the 31st closest star system to our own (excluding brown dwarfs).
In spite of these unremarkable qualities, this star is significant because it is the closest solitary white dwarf. Van Maanen's Star is an accessible (with a telescope) visual example of the eventual fate of our own sun. In six or seven billion years, after our sun has expended all of its hydrogen fuel and gone through a brief red giant phase, the remnant core of mostly carbon and oxygen will be a white dwarf star. Van Maanen's Star has an estimated mass of about two-thirds of our sun, but compressed into a volume roughly the size of the earth. No nuclear fusion is taking place - the star glows simply from the residual heat of its previous lifetime. However, because the surface area is so small (compared to the original star) it will take trillions of years to cool completely. White dwarf stars have a density of about 106 g/cm3, making them the densest form of matter other than neutron stars or black holes.
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| Rokinon 135mm f/2, 60 s, ISO 1600 |
Below is the best finder image I could come up with for the moment. The Great Square of Pegasus is in the upper left and to its right is the Pisces circlet. Down in the middle bottom a white circle marks the position of van Maanen's Star, though the star itself is not visible in this image. The brightest star within that circle is HR 222, a 5.8 mag star.
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| E-M5iii + Lumix 20mm f1.7, 60 s, ISO 1600, softon-A filter. Binned by 2. |
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