Astrophysics (Index)About

supermassive black hole

(SMBH)
(black hole with a mass of millions to billions of solar masses)

A supermassive black hole (SMBH) is a very large black hole, generally in the center of a galaxy. A black hole is considered "supermassive" if its mass is on the order of millions (or hundreds of thousands) of solar masses or more, sometimes cited as 108 through 109 as typical (as opposed to a stellar-mass black hole, likely to be about 5 to 50 solar masses). The largest observed as of 12/2019 is on the order of 40 billion solar masses. A SMBH has been detected and observed at the center of the Milky Way (named Sag A*), and it is thought that galaxies larger than dwarf galaxies generally host them. Such large black holes are considered the energy source for active galactic nuclei (AGNs), and galaxies without an AGN are presumed to host a dormant SMBH. Some methods of estimating the mass of SMBHs:

A binary SMBH (BSMBH) is a pair of co-orbiting SMBHs; they are thought to result from galaxy mergers. The terms supermassive black hole binary (SMBHB) and supermassive binary black hole (SMBBH) are used for the same pairing: no other astronomical object is of a mass-scale to be thought of as a SMBH companion.

There is a mystery regarding SMBH formation since the Eddington luminosity would seem to regulate their growth. Current SMBHs have had enough time to grow, but quasars at extreme redshifts suggest a power source that only an SMBH can provide, which would have had insufficient time to grow, and furthermore, there have not been observations suggesting some kind of atypical rapid growth in process.

Regarding terms, SBH is occasionally used to mean SMBH, but perhaps more often to mean "stellar black hole". SMBH unfortunately might be used or read to mean "stellar mass" or "solar mass", but its use as "supermassive" appears pretty consistent.


(black hole type,galaxies,object type)
Further reading:
https://en.wikipedia.org/wiki/Supermassive_black_hole
https://astronomy.swin.edu.au/cosmos/s/supermassive+black+hole
http://hyperphysics.phy-astr.gsu.edu/hbase/Astro/galcen.html
https://dictionary.obspm.fr/index.php?showAll=1&formSearchTextfield=supermassive+black+hole+%28SMBH%29
https://www.daviddarling.info/encyclopedia/S/supermassive_black_hole.html
http://spiff.rit.edu/classes/phys372/lectures/bh_evidence/bh_evidence.html

Referenced by pages:
3C 348
Abell 85 (A85)
accretion disk
accretion rate
active galactic nucleus (AGN)
active galaxy
AGN corona
binary black hole (BBH)
binary SMBH (BSMBH)
black hole (BH)
black hole accretion rate (BHAR)
black hole binary (BHB)
black hole mass function (BHMF)
black hole shadow
BlackHoleCam (BHC)
broad line region (BLR)
bulge
Centaurus A
dark matter (DM)
direct collapse black hole (DCBH)
Event Horizon Telescope (EHT)
exotic star
extreme mass ratio inspiral (EMRI)
Fermi bubbles
final parsec problem
galactic bulge
galactic center
galaxy
GN-z11
gravitational potential energy
gravitational wave spectrum
Hawking radiation
Hill radius
hypercompact stellar system (HCSS)
intermediate-mass black hole (IMBH)
IRAS 13224-3809
Kelvin-Helmholtz mechanism (KH mechanism)
Lyman-alpha forest
M-sigma relation
M87
M87*
maser
Meier paradox
Messier 106 (M106)
Messier 84 (M84)
nanohertz gravitational waves
narrow line region (NLR)
NGC 1600
NGC 7727
NuSTAR
primary
primordial black hole (PBH)
proximity effect
radio galaxy (RG)
Radio Galaxy Zoo (RGZ)
retrograde accretion
reverberation mapping
Romulus simulations
S-Star Cluster
Sag A*
Salpeter timescale
Schwarzschild radius (RS)
Sgr B2
SGR J1745-2900
SMBH formation
solar mass (MSun)
Soltan argument
Sombrero Galaxy (M104)
stellar kinematics
stellar nucleus
tidal disruption event (TDE)
X-ray source

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