PSR J1719-1438 is a

millisecond pulsar A millisecond pulsar (MSP) is a pulsar with a rotational period less than about 10 milliseconds. Millisecond pulsars have been detected in radio pulsar, radio, X-ray pulsar, X-ray, and gamma ray portions of the electromagnetic spectrum. The leadi ...

with a spin period of 5.8 ms located about 4,000 ly from Earth in the direction of

Serpens Serpens () is a constellation in the northern celestial hemisphere. One of the 48 constellations listed by the 2nd-century astronomer Ptolemy, it remains one of the 88 modern constellations designated by the International Astronomical Union. It ...

Cauda, one minute from the border with Ophiuchus. Millisecond pulsars are generally thought to begin as normal pulsars and then spin up by accreting matter from a

binary Binary may refer to: Science and technology Mathematics * Binary number, a representation of numbers using only two values (0 and 1) for each digit * Binary function, a function that takes two arguments * Binary operation, a mathematical op ...

companion. PSRJ1719-1438Location

Diamond planet

PSR J1719-1438 was discovered in (2011) by the High Time Resolution Survey, a

radio astronomy Radio astronomy is a subfield of astronomy that studies Astronomical object, celestial objects using radio waves. It started in 1933, when Karl Jansky at Bell Telephone Laboratories reported radiation coming from the Milky Way. Subsequent observat ...

search for astronomical objects that rapidly vary in radio brightness, such as pulsars. Timing measurements using the Parkes Telescope and

Lovell Telescope The Lovell Telescope ( ) is a radio telescope at Jodrell Bank Observatory, near Goostrey, Cheshire, in the north-west of England. When construction was finished in 1957, the telescope was the largest steerable dish radio telescope in the world a ...

showed that it has a low-mass companion: PSR J1719-1438 b. The companion has a mass similar to that of

Jupiter Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a Jupiter mass, mass more than 2.5 times that of all the other planets in the Solar System combined a ...

, but 40% of the diameter. It orbits the pulsar with a period of 2 hours 10 minutes and 37 seconds, at a distance of around 600,000 km (0.89

solar radii Solar may refer to: Astronomy * Of or relating to the Sun ** Solar telescope, a special purpose telescope used to observe the Sun ** A device that utilizes solar energy (e.g. "solar panels") ** Solar calendar, a calendar whose dates indicat ...

). The companion is likely the remnant of a star whose outer layers were siphoned off by the more massive pulsar. Calculations show the companion has a minimum density of 23 grams per cubic centimeter and is probably an ultra-low-mass carbon–oxygen

white dwarf A white dwarf is a Compact star, stellar core remnant composed mostly of electron-degenerate matter. A white dwarf is very density, dense: in an Earth sized volume, it packs a mass that is comparable to the Sun. No nuclear fusion takes place i ...

. Because the companion to PSR J1719-1438 is planet-sized, made primarily of carbon (with an unknown amount of oxygen), and very dense, it may be similar to a large diamond. In the science press, the object has been called the "Diamond Planet".

A lump of QCD matter

It has been suggested in 2012 that PSR J1719-1438 b may not be the remnant of a white dwarf, but a lump of

quark matter Quark matter or QCD matter ( quantum chromodynamic) refers to any of a number of hypothetical phases of matter whose degrees of freedom include quarks and gluons, of which the prominent example is quark-gluon plasma. Several series of conferences ...

with a size of just 1 kilometer and the mass of Jupiter, that would have been born in the collision and merger of two previous quark stars, part of the ejected matter ending orbiting the merger remnant we see as the pulsar PSR J1719-1438.

References

{{DEFAULTSORT:PSR J1719-1438 ? Millisecond pulsars Planetary systems with one confirmed planet Serpens

Diamond planet

A lump of QCD matter

See also

References