Questions tagged [core]

Questions regarding the material at or near the center of an astronomical object.

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How do scientists confirm iron core at the centre of the earth? [closed]

How do scientists confirm iron core at the centre of the earth? We know scientists couldn’t yet drill to the core of our planet earth. Yet we know they confirmed there is a core of iron at the centre ...
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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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What do the fusing 'onion layers' of a pre-supernova star look like to scale?

I'm sure we've all seen the diagrams of various layers of element fusion from hydrogen to silicon in a star that's just about to go supernova. (Picture from courses.lumenlearning.com) I suspect ...
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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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Why is the Earth's magnetic field stronger than its neighbors?

[Edited] I've learned that the Earth's core is hot due to decay of radioactive elements, causing the liquid part of the core to stay liquid. This was stated as an explanation to why the Earth has a ...
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How was the core temperature of the Sun estimated?

It was estimated that the heat inside the core of the Sun inside around 15 000 000 °C - this value is extremely enormous. How did scientists estimate this value?
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Frequency of Earth type cores?

I've read many interesting threads concerning the composition of different planet cores in the solar system while trying to see if this question has already been asked. It appears as if Earth is ...
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What could possibly save an atmosphere other than a magnetic field? Why can't a magnetic field save the atmosphere in certain cases?

Similar question here. We know as a fact that the magnetic field protects planets from Solar Wind, a damaging, continuous, atmosphere-stripping wind of charged ions. Thus, a magnetic field protected ...
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Is Naboo's core possible in real life?

In Star Wars, the planet Naboo has a plasma core, instead of a molten one. Can a planet really have a plasma core?
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Do all planets have a molten core?

As we know, according to Wikipedia on Earth's inner core: The Earth's inner core is the Earth's innermost part and according to seismological studies, it is primarily a solid ball with a radius of ...
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What is the underwater temperature of Europa?

If Europa has an oxygen atmosphere with a water mantle, is it possible that there could be life under the crust of Europa ice on the ocean where it is warmer? What could be the temperature under the ...
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What will happen when landing on Jupiter?

Jupiter is a gas giant, so landing on it will not be like landing on Earth, our Moon or Mars etc., as it does not have a solid surface like these. If we have a hypothetical spaceship or probe landing ...
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What is the current accepted theory as to why Mercury, despite its size, has a similar density to Earth?

According to the NASA web page overview about Mercury, despite the planet being just a bit larger than our moon, it's density is about 98.4% of Earth's. This high density suggests a comparatively ...
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What are the possible star fuels?

I always thought the only fuel for a star was hydrogen, which is fused into helium. But while reading some questions and answers here in ASO, I saw phrases like "This balance stays relatively stable ...
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Can you recommend a book about big bang nucleosynthesis and chemical abundances?

I am interested in learning about big bang nucleosynthesis, nuclear fusion up to iron in stellar cores and beyond iron in supernovas, and into the lithium problem (galactic abundance anomoly for ...
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Is there a connection between Jupiter's orbital period and the Sun's solar cycles? [duplicate]

The cycle of solar maximums and solar minimums are each about 11 years, which is close to the orbital period of Jupiter. I thought it was a numerical coincidence, until google turned up some results ...
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Are planets more likely to have dense materials at their cores?

When planets are forming, does the densest material sink the core and the less dense material "float" on top? What I'm asking is that are the more dense materials more likely to appear in the core ...
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Has the iron core of Mars really solidified?

In the Nova episode "Origins: Earth is Born", Neil DeGrasse Tyson states, "But Mars is just a fraction the size of the Earth, so it cooled more rapidly. And as it cooled, its molten iron core hardened....
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Will a planet's core always be very hot?

Including formed & forming planets, will the core of a planet always be very hot, or are there any planets with cold cores?
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Definition of stellar core?

This is a basic question, but I may as well ask it. I had always thought that the core of a main-sequence star is defined as the part hot enough for nuclear fusion. Some dictionaries seem to agree ...
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Could evaporating hot Jupiters have metallic hydrogen on their surfaces?

Jupiter is believed to have metallic hydrogen in its core. And gas giants that migrate to become hot Jupiters are believed to evaporate, have their atmospheres blown away by their nearby star. Can ...
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Is Mercury's core liquid?

A very basic question, but one to which I keep finding different answers: does Mercury have a liquid core, or is it all solid? Whatever the reason, what are the causes of it being so?
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Is Jupiter made entirely out of gas?

I heard that Jupiter is made out of gas. But in school I learned that Jupiter has gravity which is 2.5 times that of Earth (Gravity that can tear apart a comet) and gravity is proportional to mass. ...
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Could we fly/drive through Jupiter?

If Jupiter is made of gas, could we fly or drive through it or would its center be too dense?
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Mass of sun's core

It is estimated that the sun's core is about 1/5 of the radius of the sun (from Wikipedia). I know that the density of the plasma increases substantially the near the center, and that the volume of ...
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Earth and ferromagnetism [closed]

Earth's core is a giant liquid iron ball actually. If I know well, the magnetic field of our planet (that protects the surface from some particles comes from the Sun) can exist because as Earth ...
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How is it known that Callisto has no core?

My Astronomy book claims that scientists have discovered that Callisto, a moon of Jupiter, has no hot inner core. In fact, it says, Callisto has a core much like the nucleus of a comet. Is this still ...
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How do we detect if a planet has a liquid core?

In case of Earth, we have many hints about the internal structure of our planet, from what I know, the most important of which is analyzing seismic waves. Do we have any instruments to detect if ...
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Were effects of a planetary magnetic field reversal observed on other planets than Earth?

From geological records in rocks and minerals we know that the magnetic field of Earth changed its polarity multiple times in the history. See Geomagnetic reversal. Was a similar process of a ...