Category: Neutron stars

CXOU J061705.3+222127
CXOU J061705.3+222127 is a neutron star. It was likely formed 30,000 years ago in the supernova that created the supernova remnant IC 443, the "Jellyfish Nebula." It is travelling at approximately 800
Calvera (X-ray source)
In astronomy, Calvera is a nickname —based on the villain in the 1960 film The Magnificent Seven— of an X-ray source known as 1RXS J141256.0+792204 in the ROSAT All-Sky Survey Bright Source Catalog (R
4U 0614+091
4U 0614+091 is a low-mass X-ray binary star system which features a neutron star and a low-mass companion star. The binary system lies 10,000 light-years away in Orion. It produces jets like a microqu
Thorne–Żytkow object
A Thorne–Żytkow object (TŻO or TZO), also known as a hybrid star, is a conjectured type of star wherein a red giant or red supergiant contains a neutron star at its core, formed from the collision of
Neutron Star Interior Composition Explorer
The Neutron Star Interior Composition ExploreR (NICER) is a NASA telescope on the International Space Station, designed and dedicated to the study of the extraordinary gravitational, electromagnetic,
Nuclear pasta
In astrophysics and nuclear physics, nuclear pasta is a theoretical type of degenerate matter that is postulated to exist within the crusts of neutron stars. If it exists, nuclear pasta would be the s
Centaurus X-3
Centaurus X-3 (4U 1118-60) is an X-ray pulsar with a period of 4.84 seconds. It was the first X-ray pulsar to be discovered, and the third X-ray source to be discovered in the constellation Centaurus.
Chandrasekhar limit
The Chandrasekhar limit (/tʃʌndrəˈseɪkər/) is the maximum mass of a stable white dwarf star. The currently accepted value of the Chandrasekhar limit is about 1.4 M☉ (2.765×1030 kg). White dwarfs resis
A kilonova (also called a macronova or r-process supernova) is a transient astronomical event that occurs in a compact binary system when two neutron stars or a neutron star and a black hole merge. Ki
Hercules X-1
Hercules X-1 (Her X-1), also known as 4U1656+35, is a moderately strong X-ray binary source first studied by the Uhuru satellite.It is composed of a neutron star accreting matter from a normal star (H
RX J1856.5−3754
RX J1856.5−3754 (also called RX J185635−3754, RX J185635−375, and various other designations) is a neutron star in the constellation Corona Australis. At approximately 400 light-years from Earth, it i
Rotating radio transient
Rotating radio transients (RRATs) are sources of short, moderately bright, radio pulses, which were first discovered in 2006. RRATs are thought to be pulsars, i.e. rotating magnetised neutron stars wh
Quake (natural phenomenon)
A quake is the result when the surface of a planet, moon or star begins to shake, usually as the consequence of a sudden release of energy transmitted as seismic waves, and potentially with great viol
4U 1700-37
4U 1700-37 is one of the stronger binary X-ray sources in the sky, and is classified as a high-mass X-ray binary. It was discovered by the Uhuru satellite. The "4U" designation refers to the fourth (a
UY Volantis
UY Volantis, also known as EXO 0748-676, is a low mass X-ray binary system located in the constellation Volans. With an apparent magnitude of 16.9, it requires a powerful telescope to see. With a radi
3XMM J004232.1+411314
3XMM J004232.1+411314 is a low-mass X-ray binary hosted in the galaxy M31. This object is notable for being the most luminous source of hard X-rays in the Andromeda Galaxy. This is also the most lumin
GW 190814 was a gravitational wave (GW) signal observed by the LIGO and Virgo detectors on 14 August 2019 at 21:10:39 UTC, and having a signal-to-noise ratio of 25 in the three-detector network. The s
PSR J0740+6620
PSR J0740+6620 is a neutron star in a binary system with a white dwarf, located 4,600 light years away in the Milky Way galaxy. It was discovered in 2019, by astronomers using the Green Bank Telescope
Tolman–Oppenheimer–Volkoff limit
The Tolman–Oppenheimer–Volkoff limit (or TOV limit) is an upper bound to the mass of cold, nonrotating neutron stars, analogous to the Chandrasekhar limit for white dwarf stars. If the mass of the sai
XTE J1739-285
XTE J1739−285 is a neutron star, in the constellation Ophiuchus, situated approximately 39,000 light-years from Earth. It was first observed on 19 October 1999 by NASA'sRossi X-ray Timing Explorer sat
Neutron-star oscillation
Asteroseismology studies the internal structure of the Sun and other stars using oscillations. These can be studied by interpreting the temporal frequency spectrum acquired through observations. In th
X Persei
X Persei is a high-mass X-ray binary system located in the constellation Perseus, approximately 950 parsecs away. It is catalogued as 4U 0352+309 in the final Uhuru catalog of X-ray objects. The conve
1E 161348-5055
1E 161348-5055.1, commonly shortened to 1E 161348-5055, is a neutron star found in the centre of RCW103 supernova remnant. It is a periodic X-ray source with a period of 6.67 hours. It is approximatel
RX J0720.4−3125
RX J0720.4−3125 is a neutron star in the constellation Canis Major. It was discovered in 1997 in the ROSAT All-sky survey. Measurement of its parallax leads to an estimate of around 360 parsecs (1,200
HV 11417
HV 11417 is a candidate Thorne–Żytkow object, put forward in a paper by Emma Beasor and collaborators. The paper also claims that another candidate for the Thorne–Żytkow object, HV 2112, was not a Tho
Vela X-1
Vela X-1 is a pulsing, eclipsing high-mass X-ray binary (HMXB) system, associated with the Uhuru source 4U 0900-40 and the supergiant star HD 77581. The X-ray emission of the neutron star is caused by
A collapsar is a star which has undergone gravitational collapse. When a star no longer has enough fuel for significant fusion reactions, there are three possible outcomes, depending on the star's mas
KQ Velorum
KQ Velorum is a variable star system in the southern constellation of Vela. It has the identifier HD 94660 in the Henry Draper Catalogue; KQ Vel is the variable star designation. This appears as a six
Scorpius X-1
Scorpius X-1 is an X-ray source located roughly 9000 light years away in the constellation Scorpius. Scorpius X-1 was the first extrasolar X-ray source discovered, and, aside from the Sun, it is the s
Habitability of neutron star systems
The habitability of neutron star systems means assessing and surveying whether life is possible on planets and moons orbiting a neutron star. A habitable planet orbiting a neutron star must be between
Neutron star merger
A neutron star merger is a type of stellar collision. It occurs in a fashion similar to the rare brand of type Ia supernovae resulting from merging white dwarf stars. When two neutron stars orbit each
Aquila X-1
Aquila X-1 (frequently abbreviated to Aql X-1) is a low-mass x-ray binary (LMXB) and the most luminous X-Ray source in the constellation Aquila. It was first observed by the satellite Vela 5B which de
GW 170817 was a gravitational wave (GW) signal observed by the LIGO and Virgo detectors on 17 August 2017, originating from the shell elliptical galaxy NGC 4993. The signal was produced by the last mi
In astronomy, blitzars are a hypothetical type of neutron star, specifically pulsars that can rapidly collapse into black holes if their spinning slows down. Heino Falcke and Luciano Rezzolla proposed
RRAT J1819-1458
RRAT J1819-1458 is a Milky Way neutron star and the best studied of the class of rotating radio transients (RRATs) first discovered in 2006.
Neutron star spin-up
Neutron star spin up is the name given to the increase in rotational speed over time first noted in Cen X-3 and Her X-1 but now observed in other X-ray pulsars. In the case of Cen X-3, the pulse perio
LS I +61 303
LS I +61 303 is a microquasar, a binary system containing a massive star and a compact object. The compact object is a pulsar and the system is around 7,000 light-years away.
V691 Coronae Australis
X1822–371, associated with the optically visible star V691 Coronae Australis (abbreviated V691 CrA), is a neutron-star X-ray binary system at a distance of approximately 2-2.5 kiloparsecs. It is known
Neutron star
A neutron star is the collapsed core of a massive supergiant star, which had a total mass of between 10 and 25 solar masses, possibly more if the star was especially metal-rich. Except for black holes
GR Muscae
GR Muscae, also known as 2S 1254-690 is a binary star system in the constellation Musca composed of a neutron star of between 1.2 and 1.8 times the mass of the Sun and a low-mass star likely to be aro
X-ray burster
X-ray bursters are one class of X-ray binary stars exhibiting X-ray bursts, periodic and rapid increases in luminosity (typically a factor of 10 or greater) that peak in the X-ray region of the electr
The Magnificent Seven (neutron stars)
The Magnificent Seven is the informal name of a group of isolated young cooling neutron stars at a distance of 120 to 500 parsecs from Earth. These objects are also known under the names XDINS (X-ray