Gaseous layer around a planet, dwarf planet, or a star.
2
votes
2answers
28 views
Penetration of light in the atmosphere
While I was considering an answer to this question, I wondered how much light that enters the atmosphere reaches the ground without colliding with air molecules—if any. I've taken a good bit of ...
1
vote
1answer
58 views
Has martian sunset same spectra than this earthly bluish-violet sunset?
Has martian sunset same spectra than this earthly bluish-violet sunset?
What about sunset on Mercury?
0
votes
2answers
110 views
How can anything be hotter than the Sun?
I've heard that if a space shuttle enters the atmosphere from a bad angle its surface will become so hot that it will be hotter than the surface of the Sun.
How can that be? It seems to an uneducated ...
4
votes
2answers
57 views
Attenuation mass-thickness for sunset light
We are able to look directly at the sun near sunset and sunrise, which clearly demonstrates the fact that our atmosphere attenuates visible light. Let's imagine it follows the typical attenuation ...
4
votes
1answer
172 views
Can a hovering helicopter travel half the globe in 12 hours? [duplicate]
Suppose we have a helicopter that is able to stay stationary in flight for extended periods of time. If such a helicopter stayed at point A in the sky for 12 hours straight, would it reach the other ...
29
votes
8answers
9k views
Why does the atmosphere rotate along with the earth?
I was reading somewhere about a really cheap way of travelling: using balloons to get ourselves away from the surface of the earth. The idea held that because the earth rotates, we should be able to ...
5
votes
2answers
193 views
Keeping air in a giant gravitationally-bound space balloon
Let's say a space-faring society wants to make a space station that has a large volume filled with air (or other gas), but no gravity. Using normal pressure tanks will require gathering an amount of ...
2
votes
1answer
134 views
What is the cause of orange sky glow?
I live in the Netherlands and recently I have been seeing an orange glow in the sky at night, in the northwestern direction. What is the cause of this? And why is it in the northwestern direction (I ...
2
votes
1answer
148 views
What if Felix Baumgartner went the other way?
How much harder would it have been for Felix to use some powered sled and head for the ISS when he stepped out of his capsule? He was already above most of the atmosphere.
BTW, Is that capsule still ...
1
vote
2answers
182 views
Is it possible to calculate atmospheric pressure if given temperature (F) and elevation?
I am working on a report at work and need to determine the atmospheric pressure for small intervals over a 24 hour period. Searching Google, I've found charts which give a base pressure of 14.65 psia ...
3
votes
1answer
13 views
For the long-term evolution of atmosphere/orbit, when is perihelion more important than mean distance?
When we want to figure out the long-term evolution of a planet's atmosphere/orbit, when is perihelion more important than mean distance?
E.g. some processes (like Jeans Escape and escape of ...
3
votes
2answers
83 views
Assuming that the Sun wouldn't evolve into a red giant, how long would the Earth's atmosphere last?
It's not going to last forever - Jeans Escape is going to eventually act on the atmosphere after trillions of trillions of years: see http://faculty.washington.edu/dcatling/Catling2009_SciAm.pdf
5
votes
3answers
208 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 ...
2
votes
1answer
78 views
Sensors for Greenhouse Study
A group and I have the opportunity to design a payload that will be sent up some 100,000 ft (~ 30 km) into the atmosphere for approximately 3 hours. In our design, we were going to include gas sensors ...
5
votes
5answers
34 views
Which current big Earth-based telescopes are equipped with adaptive optics?
I know only that the VLT is equipped with adaptive optics (AO) to bypass atmospheric distortion. Is it the only one, or have other telescopes been build with AO in the optical and infrared spectrum?
5
votes
4answers
4k 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 ...
6
votes
1answer
30 views
Refraction and scattered light for NLCs
For helping with judging NLC candidates (are they NLC or not) I have a set of formulas to calculate the minimum altitude (in km) of the candidate given an observed altitude (in degrees) of the ...
1
vote
1answer
66 views
Equations for the two-plane model of the greenhouse effect
I'm trying to understand this "toy model" of the greenhouse effect.
http://www.realclimate.org/index.php/archives/2007/04/learning-from-a-simple-model
The model predicts the surface temperature of ...
3
votes
0answers
35 views
Special conditions at layer F2 ionosphere
I saw this graph about the electrons density in different altitudes and difference between night and day, the difference between the 2 electron densities (day and night) decreases till 300 Km (F2 ...
0
votes
0answers
33 views
Term for “atmospheric ricochet” due to wrong “angle-of-attack”
I watched "Apollo 13" yesterday, and they had the "angle-of-attack" problem that had to be manually solved, to prevent the ship from "ricochet[ing] off the atmosphere like a rock skipping off a pond".
...
1
vote
3answers
231 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 ...
2
votes
0answers
24 views
Surface UV exposure with cooler star
If the sun's surface was ~ 4000K (and earth closer to compensate), the UV component of the radiation would be less. However, UV makes ozone via photolysis of oxygen. Also, the stratosphere would ...
4
votes
0answers
63 views
Atmospheric Circulation
What is the simplest simulatable model giving our rotating earth its 3 circulation cells (Hadley, Ferrel, Polar)?
The model should also show 1 circulation cell if the earth's rotation were stopped (or ...
2
votes
2answers
158 views
Minimum size of an asteroid to actually impact earth
From what I understand, an object entering the atmosphere will start to burn up from the tremendous resistance of the atmosphere. Presumably, for asteroids under a certain size, they will burn up ...
14
votes
2answers
276 views
How deep is the Great Red Spot?
The Great Red Spot (GRS) is a very persistent storm system that's easily visible through a telescope on the surface of Jupiter. But what is the three-dimensional structure of the GRS, and how deep ...
1
vote
1answer
83 views
Is the Earth's atmosphere a Faraday cage?
X-ray telescopes are required to be above the atmosphere as the atmosphere blocks EM waves with wavelengths < UV . Does this mean that the Earth's atmosphere can be thought of as a Faraday cage ...
9
votes
1answer
335 views
Energy from man-made tornadoes
Peter Thiel just paid $300,000 to Canadian inventor Louis Michaud who is working to construct useful "man-made tornadoes" or "atmospheric vortex engines" which could be components of future power ...
10
votes
2answers
84 views
Why is Jupiter so sharply defined?
In photographs of Jupiter, the limb seems extremely definite. Being a gas giant, my naive self thinks that the atmosphere should have a more gradual cut off, creating a hazy effect similar to that on ...
2
votes
1answer
80 views
How far does typical view of clouds/atmosphere extend?
The specific "sub questions" I'm asking are:
When you are looking at clouds just on the horizon, how far away would they be?
How wide (in km) is that total field of vision at roughly cloud height.
...
2
votes
1answer
9 views
How can we be sure that liquid iron/titanium droplets can form around particulates on hot Jupiters - just as they do on Earth and Venus?
I know that we have some solar system analogs. But is there a limit to it?
3
votes
1answer
17 views
Is CO2 really a potent greenhouse gas for planets around M dwarfs?
The thing with global warming is that it absorbs infrared (IR) radiation from the planet and reradiates much of it back to the planet (whereas the Sun's peak flux is in the visible region, that is ...
15
votes
9answers
2k views
Why do space crafts take off with rockets instead of just ascending like an aircraft until they reach space?
I guess it's not a very educated question, but I never quite understood why spacecrafts have to shoot up and can't just reach space by simply continuing an upwards ascent like an airplane.
8
votes
3answers
1k views
What would happen if the polar ice caps of Mars melted?
My dad told me that Mars' polar ice caps are made of H2O and CO2. If they melt, would it add an atmosphere to Mars and allow life?
5
votes
3answers
234 views
Why is the surface of Venus so hot?
Whenever I have seen Venus described, its high surface temperature is attributed to an intense greenhouse effect. This seems to make sense, as its atmosphere is roughly 96% CO2. But on Earth, the ...
5
votes
1answer
387 views
Estimating hydrogen loss by Jeans escape
I'm looking at Jeans (thermal) escape of hydrogen from the early Earth's atmosphere. I understand how to calculate the rate in (g cm^-2 s^-1) using the number density, average particle velocity, and ...
1
vote
0answers
61 views
What is the critical mass of a planet to have an atmosphere like Earth's?
Small planets/orbits like Moon cannot have atmosphere because of their masses. They don't have enough gravity to hold an atmosphere. Then what is the critical mass that makes enough gravity to keep an ...
5
votes
1answer
267 views
Why does the sun “shine brighter” some days?
Today, the sun seems extremely bright; more dazzling than usual, and even the roads seem to be brighter so it's not just when you look up in the sky. Is more light actually getting through (perhaps ...
8
votes
1answer
246 views
What causes a ring-like image around light of the moon?
I just encountered an interesting image in sky.
As you can see in following images there was a ring-like image around light of the moon.
I don't know if it was clouds but it was looking like it is far ...
3
votes
3answers
260 views
Ozone Hole in the South Pole
Perhaps this should be a chemistry question, but it seems to have physics attributes. There's a perennial ozone "hole" around the south pole created by destruction from Cl based chemicals like CFCs. ...
3
votes
1answer
70 views
image distortion when taking a picture from space
I'm trying to understand if there is a distortion of an image taken from space (i.e. from a satellite), and if there is, then how to model it mathematically (depending on the angle in which we take ...
6
votes
2answers
150 views
Is it possible to use a balloon to float so high in the atmosphere that you can be gravitationally pulled towards a satellite?
A recent joke on the comedy panel show 8 out of 10 cats prompted this question. I'm pretty sure the answer's no, but hopefully someone can surprise me.
If you put a person in a balloon, such that ...
5
votes
4answers
1k views
Why less temperature at high altitude
Why there is always cold at high altitudes. e.g. at peak of mountains. Also as we go high from see level, temperature starts decreasing, so why is it.
12
votes
1answer
3k views
Did Felix Baumgartner produce a sonic boom during his jump?
I really got to thinking about this. The speed of sound is measured at 761.2 MPH at sea level. But how does this number change as air density decreases? The lack of air density is what allowed his ...
8
votes
1answer
2k views
From how high could have Felix Baumgartner jumped without disintegrating like a shooting star?
Today Felix Baumgartner jumped from 39 kilometres high and reached the earth safely.
Just considering friction, from how high can a human jump?
I expect that from a certain height, he would have ...
4
votes
2answers
295 views
What does the phrase “limb of the earth” or “atmospheric limb” mean?
What does the term limb of the earth (see this question, for example) or atmospheric limb mean? The phrase strikes me as very odd, since earth is nearly spherical. Do other planets with atmospheres ...
3
votes
4answers
1k views
Why the shape of rainbow is semicircular after rain why not the whole atmosphere is colorful?
I have a very simple question.
Everyone must have seen the rainbow after rain. According to the theory the rainbow is created due to the passing of sunlight from small drops of water in the ...
10
votes
5answers
9k views
Why does the road look like it's wet on hot days?
Often, I'll be driving down the road on a summer day, and as I look ahead toward the horizon, I notice that the road looks like there's a puddle of water on it, or that it was somehow wet. Of course, ...
4
votes
3answers
4k 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 ...
0
votes
1answer
308 views
Atmospheric Escape of Gas Molecules
Most of the Bodies and Objects in space are likely to have an atmosphere. Since the space is empty, the gases in atmosphere should have either dissolved or emptied into space. But, Why doesn't this ...
10
votes
2answers
278 views
Is this a weather phenomenon or an instrumental artifact?
The radar image of the midwest provided by Weatherunderground at 10:30 PM Central time, May 8 2011 has odd patterns.
Are these patterns real? Perhaps caused by large scale convection over cities? Or ...
