Washington: A team of astronomers, using multiple telescopes, have identified a faint white dwarf star that looks like diamond.
White dwarfs are the extremely dense end states of stars like our Sun: after their nuclear fuel is exhausted, they collapse from the size of a star (about 1,000,000 miles across) to the size of the Earth (7,000 miles across).
This white dwarf, located in the constellation Aquarius, is so cool that its carbon has crystallized - in other words, it`s like a diamond, with a mass similar to that of our Sun.
The path to this discovery began when Dr. Jason Boyles, then a graduate student at West Virginia University, identified what astronomers refer to as a millisecond pulsar in this location. Known as PSR J2222-0137 , which simply identifies its position in the sky, this pulsar is spinning over 30 times a second. Its orientation is such that as it spins, a beam from its magnetic pole sweeps repeatedly past the Earth, giving rise to regular blips of radio waves. (The pulsar is detected only in radio waves, not in visible light.)
The observations also revealed that this pulsar is gravitationally bound to a companion star: the two orbit around each other every 2.45 days. It is this companion object that appears to be either another neutron star or, more likely, a remarkably cool white dwarf.
The distance to the pulsar was already known from parallax measurements made by Dr. Adam Deller at the Netherlands Institute for Radio Astronomy. Parallax, which utilizes the motion of the Earth around the Sun, is the gold standard for determining distances to astronomical objects. At only about 900 light-years away, it is one of the closest neutron stars known.