A relatively small and dense object, camouflaged within a cloud that still explodes several thousand light-years away, challenges our understanding of stellar physics.
With all accounts, it looks like a file neutron bintang, even if it is unusual. With only 77 percent of the mass of the Sun, it is the lowest mass ever measured for such an object.
previouslyThe lightest neutron star ever measured is 1.17 times the mass of the Sun.
This latest discovery is not only smaller, but also well below the minimum mass of neutron stars predicted by the theory. This suggests that there is a gap in our understanding of these super dense objects … or that what we are seeing is not a neutron star at all, but a strange never-before-seen object known as “alien”. ” star.
Neutron stars are among the densest objects in the entire universe. This is what remains after a massive star with a mass between 8 and 30 times the mass of the Sun reaches the end of its life. When a star’s matter is used to fuse into its core, it moves into a supernova, ejecting its outermost layer of material into space.
No longer being pushed by external fusion pressures, the nucleus collapses on itself to form a very dense object, atomic nuclei crush each other, and electrons are forced into intimacy with protons long enough to transform into neutrons.
Most of these solid bodies have a mass of about 1.4 times the mass of the Sun, although the theory says they can range from as large as what’s around them. 2.3 solar mass, only 1.1 solar masses. All of this is encased in a ball that is crammed into a sphere about 20 kilometers (12 miles) wide, which gives each teaspoon of neutron stellar matter some weight in the middle. 10 million dollars And several billion tonne.
Stars with masses higher and lower than neutron stars can also turn into solid objects. The heaviest stars turn into black holes. Lighter stars turn into white dwarfs, less dense than neutron stars, with a maximum mass of 1.4 solar masses, although they are still quite compact. This is The final fate of our sun.
The neutron star in this study is located in the center of a supernova remnant called Hess J1731-347previously counted for sitting more than 10,000 light years. However, one of the difficulties in studying neutron stars lies in the weakness of distance measurements. Without precise distances, it is difficult to obtain accurate measurements of other stellar properties.
Recently, a second optically bright star was discovered hidden in HESS J1731-347. From here, using data from the Gaia Map Survey, a team of astronomers led by Viktor Doroshenko of Eberhard Karls University in Tübingen in Germany were able to recalculate the distance to HESS J1731-347 and found that it was closer than expected. , about 8,150 light-years away.
This means that previous estimates of the neutron star’s other properties need to be refined, including its mass. Combined with observations of the X-ray light emitted by neutron stars (inconsistent with the X-ray light emitted by white dwarfs), Doroshenko and his colleagues were able to increase its radius to 10.4 km and its mass at an extremely low only 0.77. . mass.
This means that it may not be a neutron star as we know it, but a hypothetical object that has not yet been positively recognized in nature.
“Our mass estimate makes the central compact body of HESS J1731-347 the lightest neutron star known to date, and possibly a more exotic object, namely a candidate ‘foreign star’,” The researchers write in their article.
According to the theory, exotic stars are very similar to neutron stars, but contain a greater proportion of fundamental particles called alien quarks. Quarks are fundamental subatomic particles that combine to form complex particles such as protons and neutrons. Quarks come in six different types, or flavors, called ascendants, descendants, charmers, odd, ascendants and descendants. Protons and neutrons are made up of up and down quarks.
This theory suggests that in the highly compressed environment inside a neutron star, subatomic particles disintegrate into their constituent quarks. According to this model, exotic stars are composed of matter composed of equal proportions of upper, lower and odd quarks.
Exotic stars are supposed to form under groups large enough to fit, but because the regulation for neutron stars goes out the window when enough quarks are involved, there isn’t even a nucleus. That is, we cannot rule out the possibility that this neutron star is actually an exotic star.
This would be really cool; Physicists have been looking for quark matter and quark strange matter for decades. However, while strange stars are certainly possible, the bigger possibility is that what we’re seeing is a neutron star – that’s pretty cool too.
“The mass and radius conditions obtained are still fully compatible with the standard interpretation of the neutron star and can be used to increase the astrophysical constraints on the cold solid matter equation of state in these hypotheses”, Writes the researcher.
“Such a light neutron star, regardless of its internal composition, appears to be a very interesting object from the point of view of astrophysics.”
It is difficult to be sure how such a light neutron star would form with our current model. So, whatever the material, the dense object at the center of HESS J1731-347 will have something to teach us about the mysterious life of a huge star.
The team’s research was published in natural astronomy.
