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A quasi-star would result from the core of a large [[protostar]] collapsing into a [[black hole]], where the outer layers of the protostar are massive enough to absorb the resulting burst of energy without being blown away or falling into the black hole, as occurs with modern [[supernova]]e. Such a star would have to be at least {{convert|1000|solar mass|lk=in}}.<ref name="newsci"/> Quasi-stars may have also formed from [[dark matter halo]]s drawing in enormous amounts of gas via gravity, which can produce supermassive stars with tens of thousands of solar masses.<ref name="zeroing in">{{cite web|url=https://www.scientificamerican.com/article/zeroing-in-on-how-supermassive-black-holes-formed1/|title=Zeroing In on How Supermassive Black Holes Formed|author=Yasemin Saplakoglu|publisher=Scientific American|date=September 29, 2017|access-date=April 8, 2019}}</ref><ref name="cooking up">{{cite web|url=http://www.astronomy.com/news/2017/11/cooking-up-supermassive-black-holes|title=Cooking up supermassive black holes in the early universe|author=Mara Johnson-Goh|publisher=Astronomy|date=November 20, 2017|access-date=April 8, 2019}}</ref> Formation of quasi-stars could only happen early in the development of the Universe, before hydrogen and helium were contaminated by heavier elements; thus, they may have been very massive [[Population III]] stars. Such stars would dwarf [[VY Canis Majoris]] and [[Stephenson 2-18]], both among the [[List of largest stars|largest known modern stars]], in size.
A quasi-star would result from the core of a large [[protostar]] collapsing into a [[black hole]], where the outer layers of the protostar are massive enough to absorb the resulting burst of energy without being blown away or falling into the black hole, as occurs with modern [[supernova]]e. Such a star would have to be at least {{convert|1000|solar mass|lk=in}}.<ref name="newsci"/> Quasi-stars may have also formed from [[dark matter halo]]s drawing in enormous amounts of gas via gravity, which can produce supermassive stars with tens of thousands of solar masses.<ref name="zeroing in">{{cite web|url=https://www.scientificamerican.com/article/zeroing-in-on-how-supermassive-black-holes-formed1/|title=Zeroing In on How Supermassive Black Holes Formed|author=Yasemin Saplakoglu|publisher=Scientific American|date=September 29, 2017|access-date=April 8, 2019}}</ref><ref name="cooking up">{{cite web|url=http://www.astronomy.com/news/2017/11/cooking-up-supermassive-black-holes|title=Cooking up supermassive black holes in the early universe|author=Mara Johnson-Goh|publisher=Astronomy|date=November 20, 2017|access-date=April 8, 2019}}</ref> Formation of quasi-stars could only happen early in the development of the Universe, before hydrogen and helium were contaminated by heavier elements; thus, they may have been very massive [[Population III]] stars. Such stars would dwarf [[VY Canis Majoris]] and [[Stephenson 2-18]], both among the [[List of largest stars|largest known modern stars]], in size.


Once the black hole had formed at the core of the protostar, it would continue generating a large amount of [[radiant energy]] from the infall of stellar material. This constant outburst of energy would counteract the force of [[gravity]], creating an equilibrium similar to the one that supports modern fusion-based stars.<ref name=bra08>{{cite journal|last=Begelman|first=Mitch|author2=Rossi, Elena |author3=Armitage, Philip |title=Quasi-stars: accreting black holes inside massive envelopes|journal=MNRAS|year=2008|volume=387|issue=4|pages=1649–1659|doi=10.1111/j.1365-2966.2008.13344.x|bibcode=2008MNRAS.387.1649B|arxiv = 0711.4078 |s2cid=12044015}}</ref> Quasi-stars would have had a short maximum lifespan, approximately 7 million years,<ref name=spf01>{{Cite journal| arxiv=1305.5923| title= Massive black hole factories: Supermassive and quasi-star formation in primordial halos| journal= Astronomy & Astrophysics| volume= 558| pages= A59| date=25 May 2013| last1= Schleicher| first1= Dominik R. G.| last2= Palla| first2= Francesco| last3= Ferrara| first3= Andrea| last4= Galli| first4= Daniele| last5= Latif| first5= Muhammad| doi= 10.1051/0004-6361/201321949|bibcode = 2013A&A...558A..59S | s2cid= 119197147}}</ref> during which the core black hole would have grown to about {{convert|1000|-|10,000|solar mass|sigfig=1}}.<ref name="newsci"/><ref name="bra08"/> These [[intermediate-mass black hole]]s have been suggested as the progenitors of modern [[supermassive black hole]]s.
Once the black hole had formed at the core of the protostar, it would continue generating a large amount of [[radiant energy]] from the infall of stellar material. This constant outburst of energy would counteract the force of [[gravity]], creating an equilibrium similar to the one that supports modern fusion-based stars.<ref name=bra08>{{cite journal|last=Begelman|first=Mitch|author2=Rossi, Elena |author3=Armitage, Philip |title=Quasi-stars: accreting black holes inside massive envelopes|journal=MNRAS|year=2008|volume=387|issue=4|pages=1649–1659|doi=10.1111/j.1365-2966.2008.13344.x|bibcode=2008MNRAS.387.1649B|arxiv = 0711.4078 |s2cid=12044015}}</ref> Quasi-stars would have had a short maximum lifespan, approximately 7 million years,<ref name=spf01>{{Cite journal| arxiv=1305.5923| title= Massive black hole factories: Supermassive and quasi-star formation in primordial halos| journal= Astronomy & Astrophysics| volume= 558| pages= A59| date=25 May 2013| last1= Schleicher| first1= Dominik R. G.| last2= Pallas| first2= Francesco| last3= Ferrara| first3= Andrea| last4= Galli| first4= Daniele| last5= Latif| first5= Muhammad| doi= 10.1051/0004-6361/201321949|bibcode = 2013A&A...558A..59S | s2cid= 119197147}}</ref> during which the core black hole would have grown to about {{convert|1000|-|10,000|solar mass|sigfig=1}}.<ref name="newsci"/><ref name="bra08"/> These [[intermediate-mass black hole]]s have been suggested as the progenitors of modern [[supermassive black hole]]s.


Quasi-stars are predicted to have surface temperatures higher than {{convert|10000|K|Celsius}}.<ref name="bra08"/> At these temperatures, and with radii of approximately {{convert|10|e9km|au|lk=on|sigfig=2}}, or {{convert|10|e9km|solar radius|lk=on|sigfig=2|disp=number|abbr=off}} times that of the Sun, each one would be about as [[luminosity|luminous]] as a small galaxy.<ref name="newsci"/> As a quasi-star cools over time, its outer envelope would become transparent, until further cooling to a limiting temperature of {{convert|4000|K|Celsius}}. This limiting temperature would mark the end of the quasi-star's life, since there is no [[hydrostatic equilibrium]] at or below this limiting temperature. The object would then quickly dissipate, leaving behind the [[intermediate mass black hole]].<ref name="bra08"/>
Quasi-stars are predicted to have surface temperatures higher than {{convert|10000|K|Celsius}}.<ref name="bra08"/> At these temperatures, and with radii of approximately {{convert|10|e9km|au|lk=on|sigfig=2}}, or {{convert|10|e9km|solar radius|lk=on|sigfig=2|disp=number|abbr=off}} times that of the Sun, each one would be about as [[luminosity|luminous]] as a small galaxy.<ref name="newsci"/> As a quasi-star cools over time, its outer envelope would become transparent, until further cooling to a limiting temperature of {{convert|4000|K|Celsius}}. This limiting temperature would mark the end of the quasi-star's life, since there is no [[hydrostatic equilibrium]] at or below this limiting temperature. The object would then quickly dissipate, leaving behind the [[intermediate mass black hole]].<ref name="bra08"/>

Revision as of 12:32, 31 December 2022

"Black hole star" redirects here. For black holes created from stars, see Stellar black hole. For stars that become black holes, see Supernova. For types of stars denser than neutron stars, see Exotic star. For the 1994 Soundgarden song, see Black Hole Sun.
Not to be confused with a quasi-stellar object or quasar.
Size comparison of a hypothetical quasi-star to some of the largest known stars.
A quasi-star rendered with Celestia

A quasi-star (also called black hole star) is a hypothetical type of extremely massive and luminous star that may have existed early in the history of the Universe. Unlike modern stars, which are powered by nuclear fusion in their cores, a quasi-star's energy would come from material falling into a black hole at its core.[1]

Formation and properties

A quasi-star would result from the core of a large protostar collapsing into a black hole, where the outer layers of the protostar are massive enough to absorb the resulting burst of energy without being blown away or falling into the black hole, as occurs with modern supernovae. Such a star would have to be at least 1,000 solar masses (2.0×1033 kg).[1] Quasi-stars may have also formed from dark matter halos drawing in enormous amounts of gas via gravity, which can produce supermassive stars with tens of thousands of solar masses.[2][3] Formation of quasi-stars could only happen early in the development of the Universe, before hydrogen and helium were contaminated by heavier elements; thus, they may have been very massive Population III stars. Such stars would dwarf VY Canis Majoris and Stephenson 2-18, both among the largest known modern stars, in size.

Once the black hole had formed at the core of the protostar, it would continue generating a large amount of radiant energy from the infall of stellar material. This constant outburst of energy would counteract the force of gravity, creating an equilibrium similar to the one that supports modern fusion-based stars.[4] Quasi-stars would have had a short maximum lifespan, approximately 7 million years,[5] during which the core black hole would have grown to about 1,000–10,000 solar masses (2×1033–2×1034 kg).[1][4] These intermediate-mass black holes have been suggested as the progenitors of modern supermassive black holes.

Quasi-stars are predicted to have surface temperatures higher than 10,000 K (9,700 °C).[4] At these temperatures, and with radii of approximately 10 billion kilometres (67 au), or 14,000 times that of the Sun, each one would be about as luminous as a small galaxy.[1] As a quasi-star cools over time, its outer envelope would become transparent, until further cooling to a limiting temperature of 4,000 K (3,730 °C). This limiting temperature would mark the end of the quasi-star's life, since there is no hydrostatic equilibrium at or below this limiting temperature. The object would then quickly dissipate, leaving behind the intermediate mass black hole.[4]

See also

References

  1. ^ a b c d Battersby, Stephen (29 November 2007). "Biggest black holes may grow inside 'quasistars'". NewScientist.com news service.
  2. ^ Yasemin Saplakoglu (29 September 2017). "Zeroing In on How Supermassive Black Holes Formed". Scientific American. Retrieved 8 April 2019.
  3. ^ Mara Johnson-Goh (20 November 2017). "Cooking up supermassive black holes in the early universe". Astronomy. Retrieved 8 April 2019.
  4. ^ a b c d Begelman, Mitch; Rossi, Elena; Armitage, Philip (2008). "Quasi-stars: accreting black holes inside massive envelopes". MNRAS. 387 (4): 1649–1659. arXiv:0711.4078. Bibcode:2008MNRAS.387.1649B. doi:10.1111/j.1365-2966.2008.13344.x. S2CID 12044015.
  5. ^ Schleicher, Dominik R. G.; Pallas, Francesco; Ferrara, Andrea; Galli, Daniele; Latif, Muhammad (25 May 2013). "Massive black hole factories: Supermassive and quasi-star formation in primordial halos". Astronomy & Astrophysics. 558: A59. arXiv:1305.5923. Bibcode:2013A&A...558A..59S. doi:10.1051/0004-6361/201321949. S2CID 119197147.
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