Nuetron Stars and Calvera: An Unusual Specimen

A theory to explain the possible periodic mass extinctions that take place on Earth every 30 million years or so says that a brown dwarf orbits the earth which has been dubbed Nemesis. It was also the title of an Isaac Asimov book. Asimov promoted it to a red dwarf for reasons of his own, but if Nemesis exists, it has not been found.

The new neutron star found by astronomers does not qualify to be the star that causes periodic mass extinctions either as it is not part of the solar system but instead makes its home in Ursa Minor, more commonly know as the Little Dipper.

Astronomers at Pennsylvania State University have discovered an isolated Neutron star which they have dubbed Calvera. Fans of Westerns may find the name familiar. Calvera was the villain in the 1960s Western The Magnificent Seven. Calvera is also relatively close in astronomical terms, ranging from somewhere between 250 to 1000 light years from Earth. Perhaps if hyperspace travel is developed, this will become a popular vacation destination as it is also the closest such object to our planet.

The newly discovered neutron star is a type known as a "lone neutron star" meaning there are no nearby associated supermassive star remnants, a binary companion, or radio pulsations.. Stars approximately four to eight times the mass of the sun will undergo a supernova when exhausting all of their nuclear fuel. Almost all known stars of this type are part of a binary system. During the collapse, the star will become so dense that protons in the star start to form neutrons - which is how this type of deceased star gets it names. If the star emits radio waves as pulses, it becomes an object known as a "pulsar." Stars 1.44 times the mass of our sun or smaller, including the sun itself meet a different fate and become "white dwarves."

The name Calvera may be something of a mystery unless you know that the other Isolated neutron stars known to exist were called The Magnificient Seven. Naming the new object after the villian in the sixty Western of the same name is something of an inside joke, according to one of the astronomers who dectected the object at Pennsylvania State University. Without further study it will not be known whether Calvera is an unusual example of this type of star, or a completely new object of its type.

Sources:

http://news.bbc.co.uk/2/hi/science/nature/6955769.stm

http://en.wikipedia.org/wiki/Neutron_star