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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Why do the storms of Jupiter have long life unlike that of Earth?

Recently I saw How the Universe Works. In one of the episodes, concerning Jupiter, they told that the storms on Jupiter can survive many, many, times longer than those on Earth. What is the reason ...
3
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1answer
33 views

Atmosphere model

Im working on project where I should simulate glider soaring. The goal is to create gliders that will look for regions with hot upwinds using evolution algorithms. That shouldn't be problem. What I ...
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83 views

Does anyone know the mechanism behind this double helix cloud formation?

This looks like m=2 swirling instability mode of the axisymmetric jet, but how could an axisymmetric jet form up in the sky like that?
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2answers
82 views

Why is the current atmosphere made of nitrogen (75.5%)?

As I read a book on meteorology, 4 billion years ago, atmosphere was made by steam, carbon dioxide, carbon dioxide and a few nitrogen. Then photosynthesis came, run by underwater organisms, which led ...
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1answer
23 views

Radio wave propagation in ionosphere

Radio communication is based on the concept that a radio signal incident on the ionosphere is reflected if the frequency of the wave matches the plasma frequency. But what exactly happens? Is it ...
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3answers
81 views

Is the atmospheric pressure the cause of a planet's surface temperature or is it the temperature the cause of a planet's atmospheric pressure?

I heard a climatologist on a talk show saying that one of the widely known arguments used by climate scientists to exemplify what a runaway greenhouse effect could cause to Earth's temperature and ...
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0answers
22 views

What would happen to the Earth's atmosphere if all the solar radiation was in the extreme ultraviolet?

According to this, our Earth's atmosphere is completely opaque to radiation with wavelengths less than 100 nm as this radiation has enough energy to ionize the air. Since the surface temperature of ...
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0answers
24 views

how to find whether molecules will absorb radiation of a particular wavelength or not?

I am trying to understand vertical temperature profile of Earth's atmosphere. We know that different frequencies get absorbed by molecules at certain heights. I want to show this mathematically. For ...
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4answers
748 views

How Earth protected from the gamma rays generated by Sun?

Sun is generating energy by nuclear fusion. And nuclear fusion will emit energy in the form of gamma rays. Normally earth's ozone filtering the Ultraviolet radiation. And magnetic fields of earth ...
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1answer
35 views

Why do tires need to be inflated when the temperature changes?

Why do you need to add air to your tires when the temperature drops? The temperature inside and outside of the tire is the same (let's assume that you aren't currently driving, and your car has been ...
2
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2answers
82 views

Does the gravitational acceleration change value with height?

My prof asked me to do a graphic of a given function and I have to just to vary the gravitational acceleration $g$ and the height $H$. If I know the interval in which $H$ is defined :$[500,2000]m$, ...
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17 views

Global Circulation Model of tidally locked planets for PC?

Is there some free simple Global Circulation Model that can handle tidally locked planets and can be easily compiled and used on a PC computer? It does not have to be very precise, I am interested ...
3
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3answers
78 views

Why does the air pressure at the surface of the earth exactly equal the weight of the entire air column above it

Why does the air pressure at the surface of the earth (resulting from collisions of molecules on the surface of the earth which has to do with the velocity of the particles) exactly equal the weight ...
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3answers
82 views

Why is the Moon not redder at moonrise/moonset?

Okay we all know about Raleigh Scattering, which makes the sky blue. And by the same token, sunsets appear red because sunlight traveling through more atmosphere will "lose more blueness" as it's ...
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2answers
1k views

If I shout at the sky, will some molecules reach escape velocity?

Will the sound waves, as they move higher and through less dense air, conserve energy to the point where some molecules of the rarified atmosphere attain escape velocity?
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35 views

Atmosphere: what is stratification?

Talking about atmosphere's stability, what does it mean that stratification is stable or unstable? What is stratification, exactly?
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1answer
355 views

Why some thunders sound deeper while others sound snappier?

Why does some thunder sound deeper and lower in pitch while others sound snappier and higher in pitch? I don't think there should be any difference between the lightnings and so the thunders sound be ...
0
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2answers
28 views

Use of the ideal gas law for Earth's atmosphere and the role of density

To a good approximation the atmosphere behaves as an ideal gas, with each mole of gas obeying the law: $pV_m=RT$ We can obtain the corresponding law for unit mass of air using the density $\rho$. I ...
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2answers
82 views

Why Earth's atmosphere behaves like an ideal gas?

In every book I found this sentence like an assumption, without explananions, somebody can help me understand it better?
2
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1answer
38 views

How can similar lightning strikes produce thunder with different time durations?

Here in Florida, lightning happens quite often. On occasion, I have noticed that one bolt will discharge and its resultant boom will be very very short, and then a second later another bolt will ...
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4answers
6k views

Why is the sky never green? It can be blue or orange, and green is in between!

I, like everybody I suppose, have read the explanations why the colour of the sky is blue: ... the two most common types of matter present in the atmosphere are gaseous nitrogen and oxygen. ...
0
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1answer
20 views

Is there a known shape to the pattern of spherical expansion from the center outward?

I know that atomic bombs when exploded in or under or not too far above the ground, mushroom clouds are the shape that gets made by expansion, but it has the ground as a mirror, or whatever, depending ...
0
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1answer
23 views

Final temperature of an air parcel

How would one find the final temperature of an air parcel ascending adiabatically in the atmosphere? Like which formula would you use? I used the equation of state for dry air to find the initial ...
3
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1answer
36 views

Dry adiabatic lifting

If an unsaturated air parcel ascends adiabatically in the atmosphere with an initial temperature, would the final temperature of the air parcel, when it reaches it's destination, be the same at the ...
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2answers
118 views

Can someone explain to me the concept of atmosphere opacity?

On this diagram, why is the atmospheric opacity shaped as it is? If we are able to see lights due to low atmospheric opacity, why can't we see radio waves, when the atmospheric opacity is so low ...
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2answers
52 views

U.S. Standard Atmosphere

My textbook states that "Ideally, we would like to have measurements of pressure versus altitude over the specific range for the specific conditions (temperature, reference pressure) for which the ...
2
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2answers
142 views

Why do 2.4GHz frequencies offer greater range than 5GHz routers?

I would've thought that as 5GHz is a higher frequency, and it carries more energy, it would be able to pass through walls much more easily compared to a 2.4GHz frequency- similar to how short ...
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1answer
47 views

How come the atmosphere moves with Earth? [duplicate]

now, I have read a lot of explanations on that but still can't really understand why it would happen so if you can give some examples for a such a thing happening. I mean lets say gravity attracts the ...
2
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1answer
83 views

Atmospheric pressure's effect on sound

An argument has been travelling in amongst my friends around this matter and after listening about it for 3 whole days I decided to ask it here. The Question is: Would a high atmospheric pressure ...
3
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2answers
41 views

Function to fit solar radiation data

I have ground-level radiation data of solar incoming radiation from a radiometer (cosine collector) measured along the day. In the following plot you can see PAR irradiance (ie visible light) in Watts ...
2
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1answer
55 views

Can refraction of the atmosphere be so high that the surface of a planet seems concave to its inhabitants?

In their novel Inhabited Island by brothers Strugatsky, the inhabitants of a planet think they live on the inner surface of a giant sphere because the refraction of the atmosphere makes the surface ...
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0answers
29 views

Which is the most accurate way to model the fundamental atmospheric parameters of the Earth?

I need to calculate the fundamental atmospheric parameters, I mean the actual ones, this is not an exercise but a model for a real world application so I need to take account of the humidity of air. I ...
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2answers
3k views

Why is the sun brighter in Australia compared to parts of Asia?

Background: I've lived in Philippines for several years, and visited other parts of Asia occasionally (Singapore, Indonesia, Hongkong). I just moved to Western Australia a few months ago and I ...
0
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0answers
30 views

Cause and properties of northern lights [duplicate]

If outside on a dark night in the middle to high latitudes, one might be able to see an aurora. It may be several hundred kilometers high and several thousand kilometers long, stretching around Earth ...
2
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2answers
97 views

Do we hear sounds differently on the highest mountains?

Some searching gives that above 6,000 meter altitude the air density is less than half of that at sea level. Speed of sound is about 15-20% slower and "acoustic impedance" seems to change too. Do ...
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1answer
25 views

The atmosphere's water vapour capacity

If enough energy was supplied, could all liquid water on Earth evaporate into the atmosphere? Could the atmosphere hold this much water vapour? Would the pressure and density increase as a result?
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2answers
28 views

speed of gas molecules when they escape to space

I wonder if the escape velocity of gas molecules is the same as the one of rockets, which is 7.8km/s. And do oxygen escape at all or not? Are they too heavy?
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1answer
34 views

How can I get average numbers of days wind flow from 16 direction? [closed]

Wind flow from North direction a nos. of days, Similarly from North East b nos. of days, East c nos. of days, South East d nos. of days, South e nos. of days, South West f nos. of days, West g nos. of ...
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1answer
61 views

Determine the number of days with North-East wind direction from the number of days with North and East wind direction? [closed]

I have some data like: Wind flow from north direction = “X” Numbers of days. Wind flow from east direction = “Y” Numbers of days. Then is there any formula to know numbers of days wind flows ...
4
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2answers
98 views

How hot is aurora?

Has anyone done research on how hot aurora is? I mean if it is plasma it should be hot and since it is emitting mostly green light due to nitrogen (~78%) in the air, could it then be considered that ...
0
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0answers
26 views

Variance of daylight over short periods of time?

I've searched various publication archives but I'm a signal processing engineer and not an applied physicist, so I might not be using the right terms. While I can find various average values for the ...
1
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2answers
67 views

What is the maximam distance of light that is released by a flashlight?

Recently I looked at the cloudy night sky and noticed a pale green color light moving around the clouds for about 20 min.After observation I came a conclusion that it is probably because of a light ...
1
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1answer
24 views

Meteorite hunters Search for FIREBALLS

normally meteorite hunters search for fireballs....but they totally ignore meteor showers . why so? as far as i can think meteors in meteor showers are usually produced by small particles so they ...
0
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2answers
60 views

How laminar or turbulent is air?

Consider an outdoors scenario, with good weather and no sensible air currents at the floor level. How turbulent or laminar is the air surrounding this environment?
3
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3answers
195 views

Why $e$ in the formula for air density?

I am reading a book that says that the density of air is approximately $D = 1.25 e^{(-0.0001h)}$, where h is the height in meters. Why is Euler's number $e$ used here? Was a differential equation ...
15
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3answers
3k views

Does a man on the moon experience day?

Does a man on the moon (or any other similar body) experience daytime like we do? By daytime I mean looking upward and seeing a bright "sky," not dark space. If not, then what is the reason behind ...
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0answers
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What kinds of reactions happen when bubbling air through water?

Mostly I have seen air bubbling used to remove impurities in the water itself, like exemplified in this course packet. This is called "Sparging," but I have yet to learn much about transfer between ...
15
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2answers
1k views

Why does my infrared thermometer say the sky is at -2 °C?

I just got myself an infrared thermometer. I wouldn't have been able to predict what temperature it would give me when pointing at the sky, but it turned out to be -2 °C the first time I measured, and ...
1
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1answer
21 views

Decompression speed (rate)

I've heard that decompression speed or rate in which the gas will leave the greater pressured container is equal to the speed of sound. For example, if the spacecraft gets damaged the air cannot exit ...
0
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1answer
28 views

What is the purpose of sensors and pumps with less than 1 ATM pressure?

This question is not directly a physics questions, though related a little. Previously for sensors, and currently for air pumps, I am doing some research. I have found a digital pressure sensor on ...