Movatterモバイル変換

[0]ホーム

Jump to content

Iron star

Edit links

From Wikipedia, the free encyclopedia

Hypothetical far-future compact star

Inastronomy, the termiron star has been used for two unrelated types of star:

ablue supergiant with a forest offorbidden Fe_II lines in its spectrum.
a hypothetical type ofcompact star.

Blue supergiant

[edit]

An iron star is a type ofblue supergiant which has a forest offorbidden Fe_II lines in itsspectrum. They are potentially quiescent hotluminous blue variables.Eta Carinae has been described as a prototypical example.^[1]^[2]

Compact iron star formation

[edit]

Formation of iron stars
Event type	Formation of a hypothetical type ofcompact star
Date	c. 10¹⁵⁰⁰ years from now
Duration	c. 10^10²⁶ to 10^10⁷⁶ years from now
Epoch	Extremely far future
Source	Fusion occurring viaquantum tunnelling causingnuclei to fuse intoiron-56 nuclei
Notable features	Only a possibility ifprotons do not decay
Followed by	Formation ofneutron stars andblack holes
[edit on Wikidata]

An iron star is a hypothetical type ofcompact star that could occur in theuniverse in theextremely far future, after perhaps 10¹⁵⁰⁰ years.

The premise behind the formation of iron stars states thatcold fusion occurring viaquantum tunnelling would cause the lightnuclei in ordinary matter to fuse intoiron-56 nuclei, due to its nature as the atomic nucleus with the highestbinding energy. Fission andalpha-particle emission would then make heavy nuclei decay into iron, converting stellar-mass objects to cold spheres of iron.^[3] The formation of these stars is only a possibility ifprotons do not decay. Though the surface of aneutron star may be iron according to some predictions, it is distinct from an iron star.

By the end of 10^10²⁶ to 10^10⁷⁶ years, iron stars would have collapsed into neutron stars andblack holes.^[3]

In popular culture

[edit]

The Soviet filmThe Andromeda Nebula is about a starship low on fuel caught by an iron star's gravity, with the star itself being so dim that it can only be seen in the infrared. It is based on the novelAndromeda Nebula byIvan Yefremov written whensteady state theory was dominant and iron stars were expected to exist in the Milky Way.

References

[edit]

^Walborn, Nolan R.; Fitzpatrick, Edward L. (2000)."The OB Zoo: A Digital Atlas of Peculiar Spectra".The Publications of the Astronomical Society of the Pacific.112 (767): 50.Bibcode:2000PASP..112...50W.doi:10.1086/316490.
^Clark, J. S.; Castro, N.; Garcia, M.; Herrero, A.; Najarro, F.; Negueruela, I.; Ritchie, B. W.; Smith, K. T. (2012). "On the nature of candidate luminous blue variables in M 33".Astronomy & Astrophysics.541: A146.arXiv:1202.4409.Bibcode:2012A&A...541A.146C.doi:10.1051/0004-6361/201118440.S2CID 17900583.
^^a ^bDyson, Freeman J. (1979). "Time without end: Physics and biology in an open universe".Reviews of Modern Physics.51 (3):447–460.Bibcode:1979RvMP...51..447D.doi:10.1103/RevModPhys.51.447.

Stars

List

Formation

Evolution

Classification

Early Late Main sequence O B A F G K M Subdwarf O B WR OB Subgiant Giant Blue Red Yellow Bright giant Supergiant Blue Red Yellow Hypergiant Yellow Carbon S CN CH White dwarf Chemically peculiar Am Ap/Bp CEMP HgMn He-weak Barium Lambda Boötis Lead Technetium Be Shell B[e] Helium Extreme Blue straggler
Remnants	Compact star Parker's star White dwarf Helium planet Neutron Radio-quiet Pulsar Binary X-ray Magnetar Stellar black hole X-ray binary Burster SGR
Hypothetical	Blue dwarf Black dwarf Exotic Boson Electroweak Strange Preon Planck Dark Dark-energy Quark Q Black hole star Black Hawking Quasi-star Gravastar Thorne–Żytkow object Iron Blitzar White hole