40
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How much air escapes into space every day, and how long before it makes Earth air pressure too low for humans to breathe?
Most of the Earth's atmosphere is quite close to the surface. The outer layers are very tenuous, and are primarily composed of hydrogen and helium. The lower regions of the atmosphere are well mixed, ...
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How could Mars' atmosphere be shed by solar winds, when Venus has a thick atmosphere despite no magnetic field?
I am not certain that the main cause of Mars losing most of its atmosphere was the solar winds.
Long before the solar wind was discovered scientists calculated other factors which affect how long a ...
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How much water on the earth is made from hydrogen comes with solar wind?
Here is a way of getting a rough upper bound: the density $\rho$ of the solar wind is about 4 atoms per cm$^3$ (that we can assume are hydrogen), and it travels at $v=400-500$ km/s. That means that ...
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What actually are line-driven winds?
The word "line" refers to a spectral line, i.e. an emission or absorption feature in a spectrum. In this case it's absorption.
Line-driven vs. continuum-driven winds
Stellar winds are driven ...
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15
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How much mass does the Sun lose as light, neutrinos, and solar wind?
The solar neutrino luminosity is about 2.3% of its electromagnetic luminosity (i.e. light). So the extra mass lost in the form of neutrino energy is 2.3% of your original calculation.
The average ...
- 158k
14
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How could Mars' atmosphere be shed by solar winds, when Venus has a thick atmosphere despite no magnetic field?
One of the main loss mechanisms of atmospheres escape is thermal escape (Jeans escape) into space. The average thermal velocity at a given temperature $T$ for a molecule of mass $m$ is
$$ v_{th} = \...
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11
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What is the composition of the Solar Wind?
We have very good data on the heavy metals in the solar wind from the Charge, Element, Isotope Analysis System (CELIAS) on SOHO:
Some of these elements were previously known; others were observed for ...
- 37.3k
10
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Why does the Solar Wind consist of charged particles?
You are right about the kinetic energy (ie the fast motion) of the particles being the reason, but wrong when you say
They must be of almost the same energy if so there will be no relative kinetic ...
- 10.4k
9
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What determines the speed of a star's solar wind?
The answer depends very much on what type of star you are talking about and what the driving mechanism of the wind is. Broadly we can split stars up into low-mass main-sequence stars (say $<2 M_\...
- 158k
8
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Why has Venus's atmosphere not been stripped away by solar wind?
A major factor, is that Venus' volcanoes are still active. Mars's died millions of years ago. If they were still erupting, then Mars' atmosphere would be much thicker today.
Edit: This may actually be ...
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Why does the solar wind switch to flowing straight by the time it reaches Earth?
When plasma moves in a magnetic field then the charged particles follow helical paths around the field lines, due to the $q\vec{v}\times \vec{B}$ Lorentz force. If the radius of gyration is small, ...
- 158k
8
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What are the experimental limits to the residual charge of the Sun?
Some of the comments here seem to be suggesting that there should not be any residual charge of the Sun at all because of the fact that in a conducting medium no electric fields can exist. This ...
- 3,617
8
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Why do the solar system planets go rock-gas-ice instead of rock-ice-gas when moving away from the sun?
Prelude
It is now generally accepted in the planet formation community that planets form as a side-product of the star formation process in so-called protoplanetary discs.
Protoplanetary discs have ...
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7
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Density of Plasma in Solar Corona
It depends on which region you consider. The lower corona has a plasma number density of the order of $10^9 cm^{-3}$, the upper corona about $10^5 cm^{-3}$. This is all quite variable though, ...
- 3,617
7
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What determines the speed of a star's solar wind?
All stars, and also planets, lose mass because of atoms escaping from the atmosphere that are faster than the gravitational escape velocity. This suggests already that gravity i.e. the mass of stars ...
- 3,617
6
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Energy carried by solar wind
What are the velocity, mass, and charge distribution of the solar wind.
Velocity
The solar wind speed has a large range of variation, between ~250–820 km/s [e.g., Chen et al., 2014; Gopalswamy, 2006; ...
- 1,031
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How much air escapes into space every day, and how long before it makes Earth air pressure too low for humans to breathe?
Short Answer:
According to my rough calculations at the present rate that Earth is losing its atmosphere into space, it should take over a trillion years - 1,000,000,000,000 years - for Earth to lose ...
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5
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Where will the atmosphere of our Earth go if our sun blows it away completely?
The Sun erodes a planetary atmosphere through its solar wind. Presently, the solar wind passes Earth at 250-750 kps, which is roughly ten times the Sun's escape velocity from earth orbit. So atoms ...
- 7,670
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Does a red giant star produce more stellar wind than a yellow star?
The Sun's current mass loss rate - a combination of the solar wind and radiation from the Sun - amounts to something like $10^{-13}$ solar masses per year.
The mass loss rates from red giant stars are ...
- 158k
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Is Venus' magnetosphere actually more powerful than the solar wind's magnetic field that induced it or vice versa?
Is the Venus's magnetosphere actually more powerful than the solar wind's magnetic field that induced it or vice versa?
I think you are asking whether the magnitude of the magnetic field is larger at ...
- 1,031
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Does the sun blow a bubble into the interstellar medium?
At the moment, the Solar System is inside the Local Interstellar Cloud (which is itself within the Local Bubble). The LIC has a neutral hydrogen number density of $\sim0.1\text{ cm}^{-3}$, which is a ...
- 37.3k
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Energy carried by solar wind
I'm not sure such a detailed answer to your question is available.
This book cites this paper as a source for the mass loss due to the solar wind:
$\dot{M} \sim 2.5 \times 10^{-14}\,M_\odot/yr$.
...
- 1,044
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Direction of Earth’s poles relative to the Sun’s movement around the Galaxy
There is no difference in the number of cosmic particles.
You seem to imagine that there are static clouds of gas in the universe that the sun is moving through. This is not the case. The gas in the ...
- 127k
4
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Solar Wind and Asteroid orbital behavior
Sort of, via radiation pressure and heating.
The Sun emits photons, which carry with them energy and momentum. Any flux of photons applies pressure to an object it hits; this is the basic principle ...
- 37.3k
4
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Will the Sun's solar wind push a permanent magnet out of our solar system?
No. The magnetic field has two poles, the force on the two pole of the magnet is equal and opposite. This is why a compass needle will align in the North South direction, but is not pulled towards the ...
- 127k
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The sun's SOLAR WIND VS MAGNETAR
First, magnetars are absolutely bizarre objects with magnetic fields so strong the rotation of the object can result in pair production in a vacuum.
So perhaps the two most important things that the ...
- 1,031
4
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Does the magnetic field of earth restore?
Remember that a magnetic field is just that: a field . There's no mass there. Its shape depends on the electromagnetic properties of Earth -- primarily the behavior of the outer core.
When there's ...
- 3,873
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Do Electric Charges in the Van Allen Radiation belt move in Opposite Directions?
Yes and no. The question @JohnRennie links to in his comment Analogy between magnetic bottle and Van Allen's radiation belt contains a lot of relevant information, but packaged as an answer to this ...
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4
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Why does the Solar Wind consist of charged particles?
Expanding on @Steve Lintons answer:
In physics no quantity is just large, a quantity can only be large relative to some other quantity.
So here we want to compare the kinetic energy to something, and ...
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Is there a connection between the solar wind and the cosmic radiation?
Cosmic radiation (which consists of high-energy protons and atomic nuclei) comes from the sun, other stars, even other galaxies.
Solar wind is a part of that - the part coming from the sun, which ...
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