Can we experimentally understand the interior of a star?

In summary, our understanding of stars is limited to what we can observe from its surface as the interior is considered "hidden." However, through the study of the spectrum of a star, we can see absorption lines for heavy elements, indicating that there are atoms present in the outer layers. While photons emitted from inside the star may not be absorbed due to the lack of heavy elements in the outer layers, neutrinos are able to pass through and are detected by our instruments. Additionally, seismology has allowed us to gain insight into the interior of stars by studying the distortion of sound waves on the surface.
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I have heard that whatever we know about stars experimentally is through only what we can see from its surface since the light from the interior is "hidden." However, when we look at the spectrum of a star, we do see absorption lines for heavy elements. I think the reason why that is is because when an electron of a heavy element's atom inside the star is excited and it falls back again, it emits a photon which can only be absorbed by an atom of the same element. And since there are no heavy elements (usually) in the outer shells of a star, the photon doesn't get absorbed and we see it in our detectors.

But if the latter part is true (we can see photons from inside of a star), then why is it said that the information from the interior of a star is hidden?
 
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Inside the star, there are no atoms to excite, as all material is in the plasma state - which is opaque to light. The photons emitted in fusion reactions are fully thermalised by the time they make it to the outer layers.
The absorption lines we see are from whatever is found in the top layers of the star, where temperatures are low enough for free electrons and nuclei to recombine.
 
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Besides photons, neutrinos are also emitted in the interior of stars. And those pass through the outer layers of the star just fine. We experimentally detect neutrinos emitted in the interior of our sun. Not sure about detecting ones from other stars, the flux may be too low unless the star goes supernova.
 
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We can also see what's going on inside of the star with seismology. When we put our first high-res sun-watcher satellites up, scientists discovered that they were unable to resolve the surface of the sun no matter what they did. It took a while, but eventually they realized that it was distortion due to soundwaves. Once realizing that, we now had a mechanism to look inside the star: https://en.wikipedia.org/wiki/Helioseismology
 

1. How do we study the interior of a star?

The interior of a star is extremely hot and dense, making it impossible for us to physically observe it. Instead, scientists use various methods such as stellar spectroscopy, helioseismology, and theoretical models to study the interior of a star.

2. What is helioseismology?

Helioseismology is the study of the internal structure and dynamics of a star by observing its natural vibrations or oscillations. These oscillations create waves that travel through the star's interior and give us information about its density, temperature, and composition.

3. What is the importance of understanding the interior of a star?

Studying the interior of a star helps us understand the processes that govern its formation, evolution, and eventual death. It also provides insights into the fundamental laws of physics and helps us better understand the origin and evolution of our universe.

4. Can we create a star in a laboratory for experimental study?

Although we can recreate some of the conditions of a star in a laboratory, such as high temperature and pressure, it is not possible to create a star as massive and as hot as those found in nature. Additionally, the lifespan of a laboratory-created star is too short for us to gather meaningful data.

5. How accurate are the theoretical models used to study the interior of a star?

Theoretical models of stellar interiors are constantly being refined and updated as our understanding of stars and their physical processes improves. While these models may not be 100% accurate, they provide us with a good understanding of the interior of a star and have been validated by observations and experiments.

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