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This paper https://arxiv.org/pdf/astro-ph/0204233.pdf talks about a classification system for neutron stars with Roman numerals. Is there really a classification system for neutron stars? 92.185.150.174 ( talk) 05:25, 20 November 2019 (UTC)
An unknown object with 2.6 solar masses was recently discovered when it was swallowed by a black hole. It may require its own classification. TGCP ( talk) 21:37, 24 June 2020 (UTC)
I don’t think so because Neutron Star have their own class in the stellar classification method. Astrophysyst ( talk) 01:31, 5 April 2022 (UTC)
The escape velocity from a neutron star is often stated (as in the article) to be one-third to one-half c. If the heaviest, densist neutron star is 2.0 solar masses with a radius of 12-km, this corresponds to a Schwarzschild ratio of 2.0 .... Using the formula for escape velocity it seems the escape velocity is 0.7c Is this correct? 209.150.58.4 ( talk)BG — Preceding undated comment added 02:30, 14 May 2022 (UTC)
Many of the estimates of neutron star properties reported in this article don't effectively represent the uncertainties associated with these quantities and are likely confusing to readers. For example the maximum TOV mass is quite uncertain, and I'm not sure where the 2.1 number quoted comes from, the Chamel paper explicitly gives an upper bound of about 3 solar masses, but both this paper and the Özel paper were published years before the mass measurements of J0740+6620, which gives about a 2.1 solar mass lower bound on the TOV mass. The Rezzolla paper (one of several based on multimessenger data from 170817) also has an associated uncertainty, which places a 90% credible region upper bound closer to 2.3 solar masses, which should be quoted in the article. Neither 2.1 or 2.16 are consistent with the 2.35 +- .17 solar mass number from the intro for PSR J0952–0607 at 90% confidence. In general I think the correct approach here is to quote broad ranges for these values where it is necessary, and report estimates from individual papers clearly with uncertainty. In many places it's impossible to tell if ranges quoted refer to theoretical uncertainties or just natural variation in the population of neutron stars such as: "The neutron star's density varies from... to 6×1017 or 8×1017 kg/m3", usually such a statement would explicitly say "a typical 1.4 solar mass neutron star has density such and such". I also have no idea where these numbers come from but they are certainly not from the Lattimer paper, though they may be from Cole Miller's neutron star website which is inexplicably linked to in the reference that's supposed to be Lattimer's intro to neutron stars paper. Even then these numbers don't seem to accurately reflect what the page says, which is that neutron stars will likely have central densities several times nuclear densities (i.e. several times 2.8×1017 kg/m3) a much larger range than is quoted. INLegred ( talk) 07:05, 9 February 2023 (UTC)
It is worth noting that mass limit of a neutron star is dependent on star's mass but also spin and make up. https://adsabs.harvard.edu/full/1975BAAS....7..546B - obese neutron star paper written by Harvard scholar. The Tolman–Oppenheimer–Volkoff limit (or TOV limit) is an upper bound to the mass of cold, non-rotating neutron stars, analogous to the Chandrasekhar limit for white dwarf stars. If the mass of a neutron star reaches the limit it will collapse to a denser form, most likely a black hole. This limit for a while was set at 2.1 solar mass, however this estimate was for non-rotating neutron star. However, fast spinning or rotating neutron stars mass could exceed this limit, for obvious reasons. Anyways, just wanted to ad few pointers here when talking about neutron star mass and that not everything is as clear cut as this wiki article puts it. — Preceding unsigned comment added by 81.78.138.229 ( talk) 14:47, 16 February 2023 (UTC)
There is a move discussion in progress on Talk:Neutron Star (short story) which affects this page. Please participate on that page and not in this talk page section. Thank you. — RMCD bot 11:31, 8 September 2023 (UTC)
In recent weeks, user Lithopsian has issued a complaint about the appropriateness of this image
as being a good artist's impression of a neutron star. The guideline Wikipedia:Artist's_impressions_of_astronomical_objects describes general criteria for including both government agency produced and third-party made artists' impressions of astronomical objects. According to NASA, a neutron star has enough gravity in such a small space that it bends lights similar to a black hole. [2] https://www.nasa.gov/feature/goddard/2021/nasa-s-nicer-probes-the-squeezability-of-neutron-stars The image is edited by myself from a NASA image of a black hole, but according to the NASA website it's a realistic depiction of a neutron star (with gravitational lensing) from a copyright-free source. In the past (years ago) I've uploaded space engine pictures that were deleted due to Wiki's policy. The image I've generated using editing software is public domain and has been on the Neutron Star article for nearly two years.
Lastly, Wikipedia's ASTROART guidelines are a general template but clearly state not absolute, meaning on a case-by-case basis good faith exceptions are allowed. I believe this case is applicable and request that this image be accepted back into the Neutron Star lead article. Raphael.concorde ( talk) 15:34, 13 April 2023 (UTC)
References
With reference to this excerpt:
> Neutron star material is remarkably dense: a normal-sized matchbox containing neutron-star material would have a weight of approximately 3 billion tonnes, the same weight as a 0.5-cubic-kilometer chunk of the Earth (a cube with edges of about 800 meters) from Earth's surface.
Some back of the envelope math makes me think this is wrong. If the cube is 500m to the side, then that's 500x500x500 = 125,000,000 (125 million) cubic meters. 3,000,000,000 / 125,000,000 = 24.
Does a cubic meter of earth's surface weigh 24 tons? That's about 5 wheelbarrows' worth of dirt. Data is being misused here somehow. Aerovistae ( talk) 18:42, 18 September 2023 (UTC)
Will someone tell me if this is anything other than intentional disruption? Talk:Fuzzball_(string_theory)#Evidence_of_intent_of_vandalism.
![]() | This is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
Archive 1 | Archive 2 | Archive 3 |
This paper https://arxiv.org/pdf/astro-ph/0204233.pdf talks about a classification system for neutron stars with Roman numerals. Is there really a classification system for neutron stars? 92.185.150.174 ( talk) 05:25, 20 November 2019 (UTC)
An unknown object with 2.6 solar masses was recently discovered when it was swallowed by a black hole. It may require its own classification. TGCP ( talk) 21:37, 24 June 2020 (UTC)
I don’t think so because Neutron Star have their own class in the stellar classification method. Astrophysyst ( talk) 01:31, 5 April 2022 (UTC)
The escape velocity from a neutron star is often stated (as in the article) to be one-third to one-half c. If the heaviest, densist neutron star is 2.0 solar masses with a radius of 12-km, this corresponds to a Schwarzschild ratio of 2.0 .... Using the formula for escape velocity it seems the escape velocity is 0.7c Is this correct? 209.150.58.4 ( talk)BG — Preceding undated comment added 02:30, 14 May 2022 (UTC)
Many of the estimates of neutron star properties reported in this article don't effectively represent the uncertainties associated with these quantities and are likely confusing to readers. For example the maximum TOV mass is quite uncertain, and I'm not sure where the 2.1 number quoted comes from, the Chamel paper explicitly gives an upper bound of about 3 solar masses, but both this paper and the Özel paper were published years before the mass measurements of J0740+6620, which gives about a 2.1 solar mass lower bound on the TOV mass. The Rezzolla paper (one of several based on multimessenger data from 170817) also has an associated uncertainty, which places a 90% credible region upper bound closer to 2.3 solar masses, which should be quoted in the article. Neither 2.1 or 2.16 are consistent with the 2.35 +- .17 solar mass number from the intro for PSR J0952–0607 at 90% confidence. In general I think the correct approach here is to quote broad ranges for these values where it is necessary, and report estimates from individual papers clearly with uncertainty. In many places it's impossible to tell if ranges quoted refer to theoretical uncertainties or just natural variation in the population of neutron stars such as: "The neutron star's density varies from... to 6×1017 or 8×1017 kg/m3", usually such a statement would explicitly say "a typical 1.4 solar mass neutron star has density such and such". I also have no idea where these numbers come from but they are certainly not from the Lattimer paper, though they may be from Cole Miller's neutron star website which is inexplicably linked to in the reference that's supposed to be Lattimer's intro to neutron stars paper. Even then these numbers don't seem to accurately reflect what the page says, which is that neutron stars will likely have central densities several times nuclear densities (i.e. several times 2.8×1017 kg/m3) a much larger range than is quoted. INLegred ( talk) 07:05, 9 February 2023 (UTC)
It is worth noting that mass limit of a neutron star is dependent on star's mass but also spin and make up. https://adsabs.harvard.edu/full/1975BAAS....7..546B - obese neutron star paper written by Harvard scholar. The Tolman–Oppenheimer–Volkoff limit (or TOV limit) is an upper bound to the mass of cold, non-rotating neutron stars, analogous to the Chandrasekhar limit for white dwarf stars. If the mass of a neutron star reaches the limit it will collapse to a denser form, most likely a black hole. This limit for a while was set at 2.1 solar mass, however this estimate was for non-rotating neutron star. However, fast spinning or rotating neutron stars mass could exceed this limit, for obvious reasons. Anyways, just wanted to ad few pointers here when talking about neutron star mass and that not everything is as clear cut as this wiki article puts it. — Preceding unsigned comment added by 81.78.138.229 ( talk) 14:47, 16 February 2023 (UTC)
There is a move discussion in progress on Talk:Neutron Star (short story) which affects this page. Please participate on that page and not in this talk page section. Thank you. — RMCD bot 11:31, 8 September 2023 (UTC)
In recent weeks, user Lithopsian has issued a complaint about the appropriateness of this image
as being a good artist's impression of a neutron star. The guideline Wikipedia:Artist's_impressions_of_astronomical_objects describes general criteria for including both government agency produced and third-party made artists' impressions of astronomical objects. According to NASA, a neutron star has enough gravity in such a small space that it bends lights similar to a black hole. [2] https://www.nasa.gov/feature/goddard/2021/nasa-s-nicer-probes-the-squeezability-of-neutron-stars The image is edited by myself from a NASA image of a black hole, but according to the NASA website it's a realistic depiction of a neutron star (with gravitational lensing) from a copyright-free source. In the past (years ago) I've uploaded space engine pictures that were deleted due to Wiki's policy. The image I've generated using editing software is public domain and has been on the Neutron Star article for nearly two years.
Lastly, Wikipedia's ASTROART guidelines are a general template but clearly state not absolute, meaning on a case-by-case basis good faith exceptions are allowed. I believe this case is applicable and request that this image be accepted back into the Neutron Star lead article. Raphael.concorde ( talk) 15:34, 13 April 2023 (UTC)
References
With reference to this excerpt:
> Neutron star material is remarkably dense: a normal-sized matchbox containing neutron-star material would have a weight of approximately 3 billion tonnes, the same weight as a 0.5-cubic-kilometer chunk of the Earth (a cube with edges of about 800 meters) from Earth's surface.
Some back of the envelope math makes me think this is wrong. If the cube is 500m to the side, then that's 500x500x500 = 125,000,000 (125 million) cubic meters. 3,000,000,000 / 125,000,000 = 24.
Does a cubic meter of earth's surface weigh 24 tons? That's about 5 wheelbarrows' worth of dirt. Data is being misused here somehow. Aerovistae ( talk) 18:42, 18 September 2023 (UTC)
Will someone tell me if this is anything other than intentional disruption? Talk:Fuzzball_(string_theory)#Evidence_of_intent_of_vandalism.