Questions tagged [core]
Questions regarding the material at or near the center of an astronomical object.
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Question about the core mass fraction of planets and its relation to the magnetic field
I have a question about planetary cores and their relation to the magnetic field.
Around how massive (using this in the sense of mass, not size, for clarity) does a core need to be in relation to the ...
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Clarifications on Planetary Magnetic Fields
I believe I understand this equation for the dynamo effect of planets as far as iron-nickel cores go, where ρ is density in kilograms per cubic meter, Ω is rotation speed in radians per second, σ is ...
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Is the Solar core hard?
This may seem like a weird question, but something got me thinking about it just recently.
The Sun's core is composed of mainly hydrogen and helium, and is present in the form of a extremely hot ...
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What is the maximum size for a solid celestial body such that it still can be tunneled down to the core?
Old science fiction had lots of stories that involved people exploring the center of Earth, like for example Journey to the Center of the Earth, by Jules Verne. As Earth sciences advanced, this sort ...
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Why do stars usually stop fusion at iron, even though nickel-62 has the highest binding energy per nucleon?
We know that iron is often regarded as 'nuclear ash' because of its inability to fuse with other atoms, as it has a high binding energy per nucleon. However I found that Nickel-62, grabs the title of ...
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What's the relationship between the mass of a star and the mass of its core?
What's the mathematical relationship between the mass of a star and the mass of its core?
For simplicity's sake, I'm asking about the cores of main sequence stars at birth, and by "core" I ...
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How massive does a moon have to be to have a stable magnetic field?
Is there a minimum mass or other minimum properties necessary for a body to have a strong, stable dynamo to create a magnetic field conducive for life?
For example, would it be possible for Titan to ...
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Regarding core fragmentation of a gas giant in the envelope of a red giant
We know that large gas giants, such as Jupiter, have degenerate cores. Let's say there is a hot Jupiter ($5M_J$) that orbits an F-type star. When the star expands into a red giant, the hot Jupiter's ...
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Why do massive stars not undergo a helium flash
I understand that for low-mass stars the helium flash occurs due to their degenerate helium cores. Thus the answer to this question is probably that more massive stars do not have a degenerate core, ...
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Relation between core mass and red giant mass?
Yes, the title might be confusing (I'd appreciate some more clarification on it :D ). I have an estimated mass of hydrogen in the core of a star, and how much hydrogen will be in the core when the ...
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What's the temperature of Pluto's core?
The surface is freezing-nitrogen cold, but it's typical for the temperature to increase towards the core. What's the temperature of the core of Pluto? Is the planet icy and rocky all the way through? ...
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Does the luminosity of a star on its main sequence increase or remain approximately constant?
From my understanding, the luminosity of a main sequence star should increase because, in its core, hydrogen is being burnt into helium which means that the number density of hydrogen decreases and ...
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Replenishing hydrogen in the core of the sun
How is hydrogen supplied to the core of the sun? Shouldn't the radiative zone prevent this? Shouldn't heavier helium fill the core? How much of the hydrogen can the sun fuse?
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The compatibility of the Grand Tack hypothesis with the "core-warping impact" theory of Jupiter's diffuse core
In recent years, the Juno mission revealed that Jupiter's core was much more diffuse than astronomers had expected.
One theory is that "within a few million years" of its formation, Jupiter ...
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Are there any planets or moons denser than Earth?
Earth has the highest density out of all planets, planetoids and moons of our planetary system, and also has a higher density than the Sun. Do we know any exoplanets or moons denser than Earth?
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