Questions tagged [heat]

Questions regarding thermal energy and its effect on astronomical objects.

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Why does nuclear fusion generate heat?

I understand that nuclear fusion generates energy in the form of gamma-rays (as in the pp chain), but how does that translate into heat in the star's core? Or is the heat just generated by ...
Astrovis's user avatar
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Could entropy be reversed eventually in the far future?

In the far future there will be most likely a point where a maximal state of entropy will be reached in the universe and after the last black hole evaporates there could be no more structures and no ...
vengaq's user avatar
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Why do white dwarfs cool down so slowly?

I read that when white dwarfs do not proceed with nuclear fusion, the heat radiation from it is solely based on heat it retained in the past But then, it floats in an almost 0 K empty space. So, why ...
Zoli's user avatar
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3 votes
0 answers
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What would be the effect of WR104 if it was at the distance of Alpha Centauri and pointed at us?

If WR104 was at the distance of Alpha Centauri and its pole pointed at us when it went off what effect would it have? How badly would Earth be scorched? If we were sitting right on the cannon’s mouth, ...
Mark Besser's user avatar
4 votes
2 answers
485 views

How hot would the core of the Red Giant Sun be?

After the Sun becomes a red giant, it will heat up its core to 100 million kelvins, which initiates the Triple-Alpha fusion process, which heats up the star's core even further and cause it to undergo ...
Alastor's user avatar
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1 vote
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How did cosmic inflation even occur?

I wanted to ask this question that which inflation model shall i believe? Following below will be MY UNDERSTANDING (MAY NOT BE CORRECT) OF IT: I read "A Brief History of Time" and in chapter ...
Aveer's user avatar
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0 answers
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Could the timing of the oxygen spike on Mars be used to determine if photosynthesis is responsible?

I am wondering if the timing of the oxygen spike on Mars could be used to determine if photosynthesis is the source (which would be another indication of life on Mars), or if it is purely heat related?...
Jonathan's user avatar
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16 votes
4 answers
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Can a star emit heat but no visible light?

Can a star emit enough heat to allow human life on its planets, however emit no visible light? If so, what problems would this pose?
user36985's user avatar
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1 answer
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Why has Saturn stopped contracting gravitationally?

The following text is from here: The Jovian planets get their heat from the Sun and from their interiors. Jupiter creates a lot of internal heat and releases this heat by emitting thermal radiation. ...
Nilay Ghosh's user avatar
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13 votes
2 answers
2k views

How complicated is the heating of meteors?

When any gas, including our atmosphere, is compressed, it's temperature rises. When a meteor is falling through the atmosphere, it is compressing the air below it. Because this makes the air hotter ...
BenGoldberg's user avatar
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3 answers
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Is the eventual heat death of the universe due to the expansion of the universe?

I am reading about the accelerating expansion of the universe and something struck me. The observation that things further away were accelerating away faster and that early observations made it look ...
Patrick's user avatar
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3 answers
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What is the hottest thing in the universe?

Straight from my 7 year old to you, exactly what it says on the cover: What is the hottest thing in the universe? To make it Stack Exchange-friendly, I'll add the following caveats: it should be ...
Bruce Becker's user avatar
4 votes
1 answer
179 views

What is the specific heat capacity of interstellar clouds?

Star forming molecular clouds and especially Bok globules are low temperature $\sim 10 $ K environments with density on the order of $10^{-18}$ kg/m$^3$, mostly hydrogen with about 1% dust. What is ...
Anders Sandberg's user avatar
6 votes
1 answer
329 views

How deep in Mars would a person not need insulation and pressure? [duplicate]

How deep in Mars' surface would one have to go to both not need a pressurized suit and be warm enough to just wear clothes? in other words is there a dept Goldilocks where you would only need an ...
Muze's user avatar
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12 votes
4 answers
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Why black holes are extremely cold?

"The most massive black holes in the Universe, the supermassive black holes with millions of times the math [sic] of the Sun will have a temperature of 1.4 x $10^{-14}$ Kelvin. That's low. Almost ...
Paran's user avatar
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1 answer
1k views

Is there a significant temperature difference on the moon from apogee to perigee or vice-versa?

Do those few thousand kilometers of difference going around the earth significantly affect the amount of thermal energy the moon receives from the sun to warm up its surface? Also, are there more ...
Peter Johnmeyer's user avatar
3 votes
0 answers
401 views

What is the temperature under the surface of Mercury?

What is the temperature under the surface of Mercury? I know at the surface the temperature varies greatly (-297 F to 801 F). I also realize that the answer would likely depend on depth. Do we know ...
Jonathan's user avatar
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1 vote
2 answers
493 views

gravitational energy and internal energy

So assume we have a planet of temperature T, and mass M, We can calculate it's internal energy/heat content by the formula $U=cMT$ where $c$ is the specific heat. And if we also know the ...
casualprogrammer's user avatar
3 votes
2 answers
724 views

If there was air between the Sun and Earth, how warm would we get?

Based on this question: How loud would the Sun be? If instead of a vacuum we had air between the sun and earth (let's say of the same composition we have here on earth) how warm would our planet get?
Parrotmaster's user avatar
0 votes
1 answer
1k views

The relation between the energy of star and heating effect

Because a star's temperature is an indication of the energy passing through each unit of its surface, it follows that for cool red and hot blue stars of identical luminosities, the cooler red star ...
Purple Rain Kim's user avatar
3 votes
2 answers
520 views

Is there a limit to how hot an object an get? [closed]

Temperature is a measure of the average kinetic energy of particles in a given place (correct me if I am wrong) so there must be a definite limit to heating like there is an absolute zero to cooling. ...
HotSaucey's user avatar
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4 votes
2 answers
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What Makes Stars Hot?

Simple question, but can't seem to find the answer anywhere. It can't be nuclear fusion because nuclear fusion occurs as a result of the heat. And it can't be because of gravity because it's believed ...
Badr B's user avatar
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6 votes
2 answers
11k views

What would happen if we stepped on the Sun?

I mean in intrinsic detail. What would happen to our bodies besides "burst into flames"?
Bill's user avatar
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2 votes
1 answer
141 views

Configuration required to tidally heat Earth-like rogue planet

Could it be possible for Earth-like rogue planet to maintain large bodies of liquid water on the surface without a sun by relying mostly on tidal forces of a moon (or multiple moons). How big/far/fast ...
Mirac7's user avatar
  • 139
3 votes
2 answers
865 views

Internal heat and planetary differentiation

I was reading an article on planetary differentiation, and apparently internal heat production plays a major role. There are several sources of such heat described, such as tidal heat, radiogenic heat,...
L.R.'s user avatar
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6 votes
5 answers
4k views

Does planet Earth receive any heat from other stars in our galaxy?

Does planet Earth receive any heat at all from the millions of other stars in our galaxy? Does the light that brings the heat perhaps cool down on the long journey through space to planet Earth, ...
Peter U's user avatar
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20 votes
5 answers
33k views

What would the effects be on Earth if Jupiter was turned into a star?

In Clarke's book 2010, the monolith and its brethren turned Jupiter into the small star nicknamed Lucifer. Ignoring the reality that we won't have any magical ...
Maelish's user avatar
  • 323
2 votes
1 answer
544 views

Does the sun have a protective shield

Does the sun have a protective layer that at least diminishes its radiation. I know the earth's atmosphere protects us from harmful rays. But does the sun have a sort of shield as well that if removed ...
TreeKing's user avatar
  • 139
3 votes
1 answer
889 views

Is the surface of Venus red hot?

I was wondering, is the surface of Venus so hot that it would glow red in the dark (e.g. on the dark side of Venus)? I am working on making a solar system simulator, and that would make for a great ...
Jonathan's user avatar
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4 votes
1 answer
276 views

What does it mean for a black hole to "evaporate"?

It says in this Wikipedia's article: Entropy, however, implies heat and therefore temperature. The loss of energy also suggests that black holes do not last forever, but rather "evaporate" slowly. ...
Eduardo Serra's user avatar
5 votes
1 answer
556 views

Colossus telescope, trying to outsmart aliens?

I was listening to Jeff Kuhn's talk on SETI's Colossus telescope project. Background: He explains his theory that a civilization living somewhere the galaxy would want to hide, and thus would ...
Realz Slaw's user avatar
15 votes
3 answers
2k views

How hot must a star get before it is considered to be a star?

How hot must a star get before it actually becomes a star? Why does it need to get so hot? Please find an official site to quote from, if you can.
Timtech's user avatar
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