The study of the composition or dynamics of the gaseous layers around planets, often applied to questions on Earth's atmosphere but can be applicable to all planets & moons in the solar system.

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Temperature of planets without atmosphere

I am wondering how come a planet without atmopshere loses heat in space when the space around it is a vacuum. In my understanding for one object to lose heat it must have contact with another ...
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39 views

Why do night sky appear red when it is cloudy?

Since childhood, I have seen that whenever at night, the sky is cloudy, the sky becomes red. But, clouds are grayish, so it is expected that the sky becomes more darker. But no, it is not! Why does ...
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False sunset and false sunrise time estimation

False sunset and false sunrise are described . Here is a sample day rise and set time according to AccuWheather site and calculated value of sunrise and sunset in my country. Could you please help ...
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51 views

Is a body of gas cooler in its upper portion as a result of gravity? [closed]

I read an article a couple of hours ago named Hydrostatic Lapse which makes the case for a phenomenon that I thought was well and truly confirmed; that gravity is responsible for the cooling of gas ...
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1answer
39 views

Helium confined to a gravity well

It's a well known problem that Earth is slowly losing its supply of helium due to helium's ability to "bubble off" the atmosphere. All the gas giants have significant percentages of helium in their ...
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23 views

How much will the atmospheric carbon dioxide change?

Suppose $10^{14} kg$ of carbon dioxide was released into the atmosphere and absorbed completely, what is the percentage change of carbon dioxide concentration? Take initial atmospheric mass mixing ...
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1answer
34 views

Influence of terrain elevation on air pressure

If I invert the pressure altitude equation so that I can get a nominal pressure for a given altitude, and compute the pressure altitude for Denver CO (elevation about $1600 \,m$ -- yes I know the wiki ...
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24 views

What instruments are used to determine the degree of water in the atmosphere of Mars?

More precisely, how does one go about measuring the small amount of water vapor in what is almost a vacuum by terrestrial standards?
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28 views

How can a gas giant be said to have an atmosphere?

They are made of gas, right? So, there won't be a solid-gas or liquid-gas boundary that defines where the atmosphere starts. So, if there isn't a boundary, we can't define part of it to be an ...
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34 views

Balloon aerodynamics

In this recent anime that I have seen, there is a part where an atomic bomb is sent to the stratosphere in a box, by a helium balloon. As you can see in this picture of the set-up, there is a tube ...
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1answer
92 views

What would cause an orange sky?

(I was recommended to ask this question here by the guys on World Building) I'm starting a whole new planet for a story and would like it to have an orange sky during the day. At a basic level (I am ...
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1answer
46 views

Can I launch an object into orbit using only a cannon?

My friends and I were reminiscing about our intro physics classes and decided to revisit an old problem were we were required to calculate the orbital velocity of a cannonball fired from 1 meter above ...
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28 views

Rayleigh scattering equation for optical frequencies

I would like to know if there is an empirical/generic equation for Rayleigh scattering at optical frequencies in the atmosphere, similar to the Mie scattering model from Kim and Kruse which states ...
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1answer
40 views

What would you do to measure wind speed below 50m?

Is there a radiation spectrum that could be used near the surface of the earth to fluoresce air enough to see the currents? Is there a complimentary CCD that can image that spectrum? I am looking for ...
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2answers
532 views

Would fog impair echolocation abilities?

I was driving down a major highway today and the fog was thick enough I could barely see 40 ft in front of me. I then wondered if I had had some other form of perception could I have perceived my ...
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4answers
154 views

Why doesn't atmospheric pressure crush thick walled structures?

There is one thing that puzzles me: common explanation of why don't structures collapse under the enormous atmospheric pressure (~101300N/m^2) is that the force pushing from inside balances out the ...
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1answer
49 views

Why does plugging a hole in an airplane's fuselage result in a huge (10x) atmospheric pressure spike?

While reading about uncontrolled decompression, I came across one famous airline incident, Aloha Airlines Flight 243, where the article I was reading discussed a 1-square-foot hole created in the ...
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4answers
244 views

Where does air pressure come from?

Where does air pressure come from? I thought it was from gravity or the speed of the gas resulting from its heat. However, analyzing my own hypotheses, I think that my 'heat conjecture' is probably ...
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0answers
36 views

How is convection possible in fluids, in the absence of a contact surface for any buoyant force?

I don't understand why liquids and gases are acted upon by a buoyant force. In a solid immersed on some fluid medium, the pressure pressure difference caused by gravity exerts a force on the surface ...
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73 views

Why does the sky look blue rather than violet? [duplicate]

Sky looks blue because because our eyes are sensitive to blue colour. But when viewed through a camera why don't we see violet of the sky even though we can see violet colour of other pictures taken ...
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3answers
78 views

At what energy consumption would we get a 1 degree rise in the Earth's temperature?

If energy consumption continues to rise at (say) 4% per year, how long before the heat dissipation seriously impacts climate?
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3answers
69 views

Why stars are white? According to Rayleigh Scattering

According to Rayleigh Scattering, the red waves are capable of travelling a long distance, so that only we are seeing the Sun as reddish during Sunset and Sunrise. If this was true then all other ...
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2answers
3k views

Why doesn't the evening/morning sun feel much hotter on your face?

I understand that places on the Earth's surface get hotter in summer, and in the middle of the day rather than morning or evening, because the surface of the Earth is presented 'face-on' to the Sun at ...
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0answers
55 views

Why do clouds not fall? [duplicate]

The density difference between the clouds and the atmosphere favours the clouds to fall. Why don't they?
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18 views

Acoustic/Gravity waves subject to constant wind

I'm trying to model an acoustic/gravity wave (atmospehric gravity waves) propagation through an idealized atmosphere but I'm struggling understanding the results I'm suppose to get. The atmospheric ...
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14 views

Altitude altimeter application

What is the most precise formula to calculate altitude and what parameters should i considet such as pressure, temperature, dew point, ... I am developing an altimeter app and i don't know what the ...
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5answers
2k views

Why is the sky of the moon always dark?

Why is the sky of the moon always dark compared to the sky of the earth, doesn't it have day and night like earth?
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How much of the sunshine is scattered into the space?

How much more sunshine will the earth ground receive if without the atmosphere?
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58 views

What exactly is wind?

What is wind? I think it is kind of a vibration of air particles. If so, is it a longitudinal or a transverse wave? Or is it just a bunch of air particles being pushed? Smells disperse in wind so ...
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79 views

How much atmospheric pressure (CO2) is required to carry iron oxide dust in the wind?

It is common knowledge that there are dust devils and dust storms on Mars. But can we demonstrate that the atmospheric pressure on Mars, which is 0.6% of the pressure we experience on Earth, provides ...
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1answer
34 views

How would a huge ball of air look in space from outside and from inside?

If you replaced the Earth (except the atmosphere) with air and kept the pressure linear to the center (of the now non-existing Earth) while ignoring the effects this would have on gravity and leaving ...
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3answers
79 views

If the Earth's atmopsphere spins with the earth due to friction, why is there no horizontal spiralling drag?

Imagine a bucket of paint with a spinning ball in it. The paint would form a spiral and would not all move in synchronous movement with the ball. To clairfy - In order for the Earth's atmosphere to ...
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2answers
120 views

Average surface temperature of Earth [duplicate]

I had a question in my school exam. Will the average surface temperature of the Earth be lower or higher, if there was no atmosphere? Now, the answer expected is "The avg temp will be lower, because ...
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0answers
37 views

Explanation for strange atmospheric phenomenon

OK, I've seen this strange thing in the sky sometimes. Not all that often, but sometimes. It actually happened tonight. On most nights, at say 9 P.M. it is dark. There might be stars, moon, ...
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32 views

Difference between mixing ratio and mole fraction

I have been reading 'The Atmosphere of Venus' by V.I. Moroz which is available here. I am confused about the term 'mixing ratio' which is used on discussions in chemical composition. From what I ...
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3answers
218 views

Could the sky on a planet theoretically be any color?

The sky on the Earth is blue. Could the color of the sky on a planet with an atmosphere be of any color theoretically? Which colors are the most likely? I think it would be really awesome to have ...
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2k views

How much do we float in atmosphere?

The atmosphere is a fluid and we have volume, therefore we displace some of it and some buoyancy force must exist. How strong is it? How much does it affect gravitational acceleration on the surface ...
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29 views

Underwater nuke - why does the shock wave first become visible at the top of the plume?

Seen at 0:30 seconds in, this video of Operation Crossroads Baker nuclear test the condensation behind the shock wave seem to become visible initially at the top of the plume - why?
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25 views

Modeling atmospheric reentry with respect to the rotation of a planet and its atmosphere in a simulation

I am creating a hard science fiction flight simulator. I am a civil engineering student, so its a little out of my area of study. Currently I model air resistance on the velocity difference between ...
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2answers
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Why doesn't Earth's atmosphere form bands due to different rotational speeds?

If the Earth's atmosphere is rotating at the same speed as Earth, then the atmosphere must be rotating much faster at the equator than at the poles. If you spin a ball covered in oil, it will form ...
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0answers
43 views

Bulk and dynamic viscosity in the atmosphere

I'm studying the physics of the atmosphere but I'm struggling with the matter of viscosity (Navier-Stokes equation) for gravito-acoustic waves. From Landau-Lifschitz : $$ (T)_{ij} = -p\delta_{ij} + ...
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67 views

Calculating saturation mixing ratio for water in air

If I have air pressure (in, say, Pa) and air temperature (in, say, K) - how do I calculate the saturation mixing ratio for water? I can't seem to find it anywhere and it's a fairly useful quantity to ...
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1answer
181 views

Why I can't feel the difference of atmospheric pressure between a closed room and outside?

As far as I know atmospheric pressure is the result of the weight of earth's atmosphere. It has an approximate value of $10^5 Nm^{-2}$. Then why I can't feel it? My physics teacher told me that we are ...
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1answer
27 views

Regarding satellites and their 'safety'

Are satellites nowadays designed so that if one fails or its orbit degrades the scientists involved can send it various codes so that it will starts to 'beak-up' into smaller and smaller parts where ...
3
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2answers
592 views

What air pressure is needed on mars, to have fluid water?

The atmospheric pressure on the Martian surface averages 600 pascals (0.087 psi), about 0.6% of Earth's mean sea level pressure. There is a lot of frozen ice on mars, but it can't melt, because of ...
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1answer
432 views

What is the temperature of the clear night sky from the surface of Earth?

Before you all jump in with 2.73 K or thereabouts, this is more of an experimental question. It will obviously depend on humidity and radiation being scattered back towards the surface of the Earth. ...
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1answer
62 views

What does “downshear” mean?

I occasionally read descriptions such as "downshear of the vortex" in meteorological publications. What does this mean?
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98 views

Why Do Clouds Precipitate Rather than Fall From the Sky?

After spending some time watching clouds, it occurred to me how interesting it is that clouds have more structure than just being homogenous, really humid layers in the sky. I see that a similar ...
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1answer
100 views

How does heating in the atmosphere look above 100 km

I have tried without luck to find a graph of temperature change through the atmosphere that goes further up than about 100 km. On this graph: (Source: ...
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4answers
612 views

How is wind created?

I know that 'blowing air is called wind', but what I don't know is, how is wind created? And I don't want the answer from Google Search. I want to know more about wind at the atomic or molecular ...