Astronomers more precisely estimate the diameter of neutron stars
Using several different techniques, astronomers now estimate that the typical neutron star will have a diameter of 11 kilometers, or about 7 miles.
What is significant about this new estimate is that if that neutron star happens to be orbiting a black hole and get pulled into it, it will be swallowed whole instead of being ripped apart.
Their results, which appeared in Nature Astronomy today, are more stringent by a factor of two than previous limits and show that a typical neutron star has a radius close to 11 kilometers. They also find that neutron stars merging with black holes are in most cases likely to be swallowed whole, unless the black hole is small and/or rapidly rotating. This means that while such mergers might be observable as gravitational-wave sources, they would be invisible in the electromagnetic spectrum.
In other words, such cataclysmic events would be largely invisible to observers.
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Using several different techniques, astronomers now estimate that the typical neutron star will have a diameter of 11 kilometers, or about 7 miles.
What is significant about this new estimate is that if that neutron star happens to be orbiting a black hole and get pulled into it, it will be swallowed whole instead of being ripped apart.
Their results, which appeared in Nature Astronomy today, are more stringent by a factor of two than previous limits and show that a typical neutron star has a radius close to 11 kilometers. They also find that neutron stars merging with black holes are in most cases likely to be swallowed whole, unless the black hole is small and/or rapidly rotating. This means that while such mergers might be observable as gravitational-wave sources, they would be invisible in the electromagnetic spectrum.
In other words, such cataclysmic events would be largely invisible to observers.
The support of my readers through the years has given me the freedom and ability to analyze objectively the ongoing renaissance in space, as well as the cultural changes -- for good or ill -- that are happening across America. Four years ago, just before the 2020 election I wrote that Joe Biden's mental health was suspect. Only in this year has the propaganda mainstream media decided to recognize that basic fact.
Fourteen years ago I wrote that SLS and Orion were a bad ideas, a waste of money, would be years behind schedule, and better replaced by commercial private enterprise. Even today NASA and Congress refuse to recognize this reality.
In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
Please consider supporting my work here at Behind the Black.
You can support me either by giving a one-time contribution or a regular subscription. There are five ways of doing so:
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Interesting. Since most black holes have an accretion disk around them is it likely that the neutron star will simply sweep all that up as it spirals in? Or will it amass an accretion disk of it’s own on the way, which would then be the source for an electromagnetic signature of a merger event, as presumably that would get heated up and radiate pretty impressively as natural part of the process.
As you like to say Bob, the uncertainty of science : )
If I understand correctly, the paper argues that rather than lose atmosphere over time, as in the case of a white dwarf orbiting a supergiant, the neutron star is taken entire into the black hole’s accretion disk, and then *fwoop*, a star is gone.
It seems that the neutron star could not form an accretion disk, as it would have to capture material from the black hole’s disk. For that to happen, would not the gravitational attraction of the neutron star have to exceed the radial velocity of the black hole’s disk?
tangentially related….
“Galaxy surveys and the possible breakdown of the standard model of cosmology”
Paris Astrophysics Institute
September 2019
https://youtu.be/UTt0de23pXc
1:07:08
Black hole, “Burp”