All Questions
Tagged with astronomy thermodynamics
17
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The expectation value of intersecting particles
If I have a light beam (a straight line)
it goes through a box of dust, which has travelling length $l$, dust molecule cross section $\sigma$, dust number density $n$.
how to calculate the expectation ...
- 157
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Is there a galactic "goldilocks" region in the galaxy
I'm wondering if there's a region where the star density in the galaxy create the conditions in outer space where the galactic temperature is between 0 and 200°F. This may cause a ring shaped where ...
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Can dark matter be isolated from baryonic matter?
The above is an image to test Verlinde's emergent gravity theory (2016, https://arxiv.org/abs/1611.02269). The research team observered galaxies and masses beyond, used gravitational lensing (y-axis) ...
- 117
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Time of collapse of stellar dust cloud
A stellar gas cloud collapses onto itself once it reaches Jean's mass, and the time it takes for said cloud to collapse is given by: $t_{coll}=\sqrt{\frac{3\pi}{32G\rho_0}}$, where $\rho_0$ is the ...
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Can the four Seasons of planet Earth be defined in terms of Energy? [closed]
Can the four Seasons of planet Earth be defined in terms of Energy?
The definition of Energy gotten from Google is:
ability to do work, which is the ability to exert a force causing displacement of ...
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How does Viscosity of the Sun varies as we go from core to the convective zone?
How does Viscosity of the Sun varies with its radius?
For. eg, Here is the graph of the Density of the sun v/s radius. I am looking for the Viscosity v/s radius plot.
- 21
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Thermodynamic ensemble of Stars instead of molecules
If we take an enormous amount of molecules (an ensemble), the laws of statistical thermodynamics become valid: we can use them to make predictions of the macroscopic behavior of the ensemble.
I was ...
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Can we measure the black-body radiation/ electromagnetic radiation that pass through some point P in space?
I was wondering if we can measure the black-body/electromagnetic radiation energy of a point in space without actually knowing the source of this energy.
Let us say 2 stars emit black-body radiation/...
- 350
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Constant Internal energy of universe and its original source [duplicate]
While I was studying thermodynamics I am confused about internal energy of universe. here a question confused me. "If the internal energy of the universe is constant then where did all energy ...
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Can Hawking radiation be observed from the radiation (spectrum) of M87*?
Using $M87^*$ data from EHT observation (mass, temp of the surrounding accreting disk) and approximating area of EH by euclidean geometry $4\pi r^2)$, error comes around of order one or two.
One gets ...
- 3,043
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Could light and heat reflecting off of surface ice on Earth have a noticeable impact on the sun?
If so, what could be the impact of these reflections on the sun during an ice age on Earth?
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How do we quantify and measure the net entropy of today's universe?
We know that the Universe evolved from a very low entropy state in the early universe to very high entropy state of today's universe.
What is the quantitative definition of the net entropy of the ...
- 11.7k
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Can a gas be modelled as a low density blackbody, if we want to consider how detectable it will be in space?
The answer to this question taught me about the sort of parameters I need to consider if I want to consider how "detectable" an object in space is.
I want to consider the detectability of a ...
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4
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How does the formation of a solar system not break the second law of thermodynamics?
Please forgive: I am a layman when it comes to physics and cosmology, and have tried finding an answer to this that I can understand, with no luck.
As I understand it, the solar system evolved from a ...
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Why aren't gas planets and stars fuzzy? [duplicate]
The edge of Jupiter looks very sharp.
Even more bothersome, the edge of the sun looks sharp, aside from kind of a soup of particles floating above it.
The sun's surface has an incredibly low density....
- 21.1k