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 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 ...
2
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0answers
31 views

What is the mean ionospheric height?

I am reading some articles about the ionosphere and I am a little bit confused about the terms mean ionospheric height and effective height of the ionosphere. Are these the same thing? I would ...
8
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1answer
102 views

What is the reason of the semidiurnal pressure oscillation in the atmosphere?

It appears that in many (most) places on earth, a pressure oscillation of a 100-200 Pa takes place twice a day : that is, with maxima around 12AM and 12PM and minima around 6AM and 6PM. I've found ...
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2answers
61 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
154 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
40 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 ...
0
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1answer
21 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
24 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 ...
25
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3answers
3k views

Why doesn't rain fall down in streams (as opposed to drops)

Why is it that raindrops don't collide and 'stick together' on their descent to Earth, arriving in streams rather than separate drops?
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2answers
298 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
60 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
585 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
63 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 ...
6
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2answers
76 views

Stratospheric ship

Let's assume that we build a giant steel hull in a shape of cube with open top (2km long edge) and lift it to the top of stratosphere and then pump air out of it. Would it float on the outer layer of ...
3
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2answers
59 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
56 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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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 ...
3
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2answers
209 views

Loopy lightning

What causes lightning to follow the path it does ? picture from BBC news: http://news.bbcimg.co.uk/media/images/62891000/jpg/_62891901_untitled-1copy.jpg main page: ...
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0answers
33 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
351 views

How are the northern lights produced?

Although I've never seen it myself, I hear the northern lights are a sight to be seen! I know they're related to the Earth's magnetic field but I don't know much more about them. What is the physical ...
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0answers
31 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
153 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 ...
2
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4answers
654 views

Would the rate of ascent of an indestructible balloon increase as function of it's altitude?

Assume a balloon filled with Hydrogen, fitted with a perfect valve, and capable of enduring vacuum (that is to say, it would retain it's shape and so well insulated that the extremes of temperature at ...
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4answers
13k views

How does carbon dioxide or water vapour absorb thermal infra red radiation from the sun?

We are all told at school water vapour and carbon dioxide are the top two greenhouse gases, and that they absorb thermal infra red radiation, trap heat and warm up the Earth. My question is how do ...
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2answers
74 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?
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1answer
28 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
34 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
63 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
100 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 ...
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0answers
28 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 ...
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2answers
69 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 ...
6
votes
4answers
104 views

Bulk flow of air in a long tube between Antarctica and Australia?

I have a 5km diameter clear plastic tube which is open at each end and runs from the center of Antarctica to Lake Eyre in Australia. The tube is on the ground where it can be and at sea level on the ...
1
vote
1answer
25 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 ...
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5answers
1k views

Can low-gravity planets sustain a breathable atmosphere?

If astronauts could deliver a large quantity of breathable air to somewhere with lower gravity, such as Earth's moon, would the air form an atmosphere, or would it float away and disappear? Is there a ...
0
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1answer
42 views

Is it possible to more cloud-layers go to different ways on the sky

Sometime when I see the sky I see that the cloud-layers go to different ways. But how is it possible?
3
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3answers
205 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
59 views

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 ...
32
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9answers
7k views

Why can't we see gases?

I am not sure what causes gas molecules to be invisible.This question may look silly but I really want to know the story behind it.
3
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1answer
67 views

Why formation of rain is adiabatic?

I recently went through the wikipedia page for Rain. It said that There are four main mechanisms for cooling the air to its dew point: adiabatic cooling, conductive cooling,.... It proceeds as ...
0
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1answer
31 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 ...
4
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4answers
9k views

How can I calculate Vapor Pressure Deficit from Temperature and Relative Humidity?

I have a series of measurements of temperature and relative humidity (RH), together with mosquito capture data. Because mosquitoes are sensitive to desiccation, it's reasonable that RH may be useful ...
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 ...
7
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2answers
1k views

Why is getting a tan in the evening less likely than getting a tan in the morning?

When I was young I read one book in which is written that you get more tan on the morning than on evening even light angle from Sun to Earth is the same. Don't remember exact reason, I think because ...
0
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1answer
58 views

Launching a unpropelled rocket

I have read about the application of railguns and other ground powered launch, where there is no need to carry any propellant in the rocket. I am wondering, to what velocity should the vehicle ...
1
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2answers
86 views

Creating a atmosphere bubble in space with electromagnetism

would it be possible to contain an atmospheric bubble in space with a magnetic field, and wouldn't doing so protect it from solar radiation also?
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0answers
33 views

Help with vacuums?

Okay, here is my understanding. Please correct me if anything here is incorrect. Suppose I have a cube with a side length of ten inches. It has a surface area of 600 square inches, and at an ...
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3answers
132 views

Latent heat of condensation

Regarding atmospheric processes, I understand that energy is required to evaporate water by moving molecules further apart i.e. a phase change from liquid to gas. The air then ascends into the ...