Questions tagged [atmospheric-effects]
Questions about the influences of Earth's atmosphere on astronomical observations.
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Why is moon light not the same color as sunlight?
The light from the moon is light being reflected from the sun. The sun, in space, is white. But on Earth, when the light is filtered through an atmosphere, the light appears yellow. So then, why is ...
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Why doesn't the moon twinkle?
Stars twinkle because their light has to squeeze through several different layers of the Earth's atmosphere. So why doesn't the moon twinkle as well?
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How could a hobbyist astronomer determine apparent magnitude of a star?
Apparent magnitude is a rather complex way to determine the brightness of a star. Quoting the introduction text from the linked to Wikipedia page:
The apparent magnitude (m) of a celestial body is ...
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Terrestrial Exoplanet Skies – I've Built a Visual Sky Chart. Is it Accurate?
I'm an artist (and science enthusiast) and I've been trying to find a comprehensive resource that would help me clearly identify likely sky colors (as perceived by human vision) for exoplanets that ...
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Why can't moon light (reflected sun light) turn the sky blue?
Does turning the colour of the sky blue need more luminous light? Does it depend on luminosity or some other factors are also responsible for this phenomenon? Why can't the moon light turn the sky ...
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How much clearer are stars in earths orbit?
As a child I remember my parents taking camping in California, and upon stepping out of the car I was awestruck at how thick the Milky Way galaxy was and at the number of stars everywhere. I've always ...
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What it the outer part of the sun, that we see with our eyes, called?
When we look at the sun with our eyes it seems much larger than it actually is. When we use a solar filter we are seeing what the sun actually is.
So, what is the name of the thing the solar filter is ...
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Why are fewer stars seen next to the horizon?
I was in the desert the other day, in an area that was free of light pollution.
While it was easy to see the stars above us, I noticed that near the horizon, even when there is no distance light, we ...
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Is Earth unique in its fairly clear atmosphere?
So, we have surface pictures from two alien planets, Venus (captured by the Venera 13), and Mars (captured by the rover).
Both of these pictures appear to be very dusty. For Venus we see strong ...
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How would rainbows appear on other planets?
Are other planets capable of producing rainbows? How would those rainbows appear? Can rain, clouds or ice from elements other than water produce rainbows?
Related: https://space.stackexchange.com/...
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What was the first astronomical measurement which demonstrated that "the Earth is surrounded by vacuum"?
The question Who was the first to realize that the Earth is surrounded by vacuum? was closed because some users felt it was answered by answers to a different question in an different SE site: Who was ...
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How would astronomical seeing on Mars differ from that on Earth?
Astronomical seeing is the limiting factor for the resolution of all but the smallest Earthbound telescopes.
Source
Stunning advances in adaptive optics (along with it's predecessor speckle ...
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Do radio telescopes see other stars better at night?
As you know, we don’t see stars with the naked eye during the day because of the visible glare of our Sun.
As I understand our Sun emits radio frequency waves, too. Is there a radio ‘glare’ from the ...
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Oldest Reference to Astronomical Seeing
I'm writing a paper on astronomical seeing. Sir Isaac Newton identified both the phenomenon and origin of astronomical seeing in his Opticks. He writes:
If the Theory of making Telescopes could at
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How large does refraction become in radioastronomy?
For atmospheric refraction of visible light, Wikipedia gives the order of 1 arc minute at 45° altitude above the horizon, and 5.3 arc minutes at 10°. This is caused by the dielectric polarizability of ...
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How will "modern equipment" allow the Royal Observatory to now avoid some of the effects of light pollution at Greenwich?
The article First Light: a new era for the Royal Observatory says (in part):
25 June 2018
The first modern, research-grade telescopes have just been installed at the Royal Observatory Greenwich, ...
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Is it possible to see Saturn from Titan's surface, day and night?
Titan is the only moon in our solar system with a thick atmosphere, similar to what our Earth's atmosphere was before life "appeared". It also orbits Saturn close enough to actually see it beautifully ...
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Impact of Atmospheric Water vapour on Optical Observations
I would like to ask; how does Water Vapour in the atmosphere interfere with astronomical observations? Is it in the same manner as Carbon dioxide?
What brought this to mind is the following: A ...
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Meteors arriving to a planet's atmosphere?
Imagine a planet with little or no wind activity or precipitation, but that still has an atmosphere. When a meteoroid reaches the atmosphere and burns, it converts into dust and gas. Does this gas and ...
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Why is blue light extincted more strongly than red?
We know that blue light suffers extinction more strongly than red (examples include ISM, atmosphere etc.), but why? Is it a property of the shorter wavelength itself? Can someone provide a conceptual ...
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Could spy satellites use laser guide stars (for adaptive optics)?
Are sodium lasers useful for Earth observing space telescopes/spy satellites?
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Energetics of Titans Tholin haze
So, I've googled and wiki'd on this, but no clue, so I turn my question to the community:
Given Titan's nice orange haze that is supposedly composed of Tholins and strangely coincides with its ...
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Do stars twinkle when seen from Mars' surface?
Mars' average atmospheric pressure is 0.006 atm (0.088 psi). Is that enough to make fixed stars on Mars' night sky twinkle? Do we know an air pressure or density limit for that?
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Does the earth's atmosphere act as a spherical lens and refract light from space?
If so by how much does it "spoil" the view of stars and galaxies etc.
Is this error noticable, when compared to pictures taken from outer space.
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Would a red dwarf star resemble our own Sun at sunset to an observer on a nearby planet?
Suppose you're observing a red dwarf star at Noon from the surface of an Earth-like planet orbiting in the red dwarf's habitable zone, so that the red dwarf's luminosity is equal to our own Sun.
Aside ...
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What is causing this strange shimmering pattern of light during a total solar eclipse?
Below this question was left a comment linking to the Smarter Every Day video Space Station Transiting 2017 ECLIPSE, My Brain Stopped Working - Smarter Every Day 175.
At about ...
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When are wedge prisms used to correct chromatic effects of atmospheric refraction? (atmospheric dispersion)
Atmospheric refraction (shown below) happens because Earth's atmosphere has an index of refraction that differs from unity.
@MikeG's comment mentions that this refraction would have a chromatic ...
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Why is it that night has a almost a bluish tint to it instead of red?
From my understanding/been told, the color red has the ability to travel the farthest in our atmosphere, being the reason why we have red sunsets and such. But with this in mind, why is it that at ...
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Can you see city lights on the Moon from Earth?
This is the opposite of another question. That question is about whether you could see cities on Earth if you were standing on the Moon.
Let's there are cities on the Moon and you're standing on the ...
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Fixed star-like light appears for a second or two - is there a way to find out what it was?
I saw what I can only describe as a fixed point of light, as bright as a shooting star, near Alpheratz for a second or two before disappearing. I am positive it wasn't a satellite nor a plane. There ...
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Why is only a narrow chunk of sky darkened in this amazing Curiosity solar eclipse GIF from Mars?
I found three NASA JPL images in the sequence PIA23133, PIA23134, and PIA23135. They were taken by the Curiosity Rover on Mars and show solar eclipses by Mars' two moons.
Details of these images are ...
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Under what situations can an aperture mask improve the resolution of a small/medium amateur telescope? Is this demonstrable mathematically?
@antlersoft's answer describes some of the challenges to seeing any details in the small disk of Mars in small amateur telescopes. In the case of reflecting telescopes, it mentions the use of either ...
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Do the gases in the Earth's atmosphere affect the color of a lunar eclipse?
As the sun's rays pass through the Earth's atmosphere only the red light gets through. Is this the result of specific gases in the Earth's atmosphere filtering the red light? Does all of the nitrogen ...
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How many stars can be seen naked eye from outside the atmosphere? How dense is the "sky" from there?
When I was 20, I went to Naxos (Greece) with friends. I was driving my car during the night on the mount Zeus (1003 meters - 3,291 ft) listening Pink Floyd.
Up there we stopped the car to take a walk,...
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Effect of particulates on the visibility of stars?
I am looking for a (mathematical) relationship - either empirical or theoretical - which quantifies how the visibility of celestrial objects decreases with increasing amount of particulates in the air....
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Formula for sun's atmospheric refraction below the horizon
I have searched in Google and found interesting articles for atmospheric refraction influence on sun's elevation above the horizon (from 0° till 90°).
eg. Bennett G.G. etc.
I would like to know if ...
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What is meant by "there is no refraction at the zenith"?
Wikipedia states:
Atmospheric refraction of the light from a star is zero in the zenith
and other sources seem to agree.
I don't see why this should be so. Consider a situation in which air gets ...
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What conditions are necessary for the sun to look [as described below]
First of all sorry for the weird title. I have no idea how to describe it in a succinct way because I've never heard of something similar happening and I've only witnessed it once. The only way for me ...
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What can be learned from low frequency radio astronomy available outside of Earth's ionosphere?
As discussions and answers to How large does refraction become in radioastronomy? point out, it is difficult to do radio astronomy much below 30 MHz (or 10 MHz depending on how aggressive you are in ...
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Are the darker blue/black areas in this picture what the atmosphere of Jupiter looks like without clouds?
This is a picture (mosaic?) of Jupiter's south pole taken by Juno (also shown below). It has gotten a lot of press, but I haven't seen anything, even in the scientific paper that accompanied its ...
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What is tilt anisoplanatism for Laser-guide-star usage in adaptive optic systems?
How does tip-tilt mirrors correct such issue? What is the physical origin of the error?
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Does the summit of a small mountain offer better seeing?
I have a small amateur telescope, and would like to defeat the atmospheric seeing conditions as much as is possible.
Fortuitously, I happen to live fairly close to this lovely patch of bare elevated ...
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Understanding energy loss in a telescope aperture due to atmospheric dispersion
I'm trying to understand energy losses due to atmospheric dispersion, given the plot below from the Keck telescope.
For a typical seeing I'm told that there's 80% encircled energy in 1". The ...
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Which kinds of astronomical observations most need to avoid the Moon being up?
This comment to Did nobody in the Astronomy community think 12,000 new satellites in LEO might be a problem? links to Phys.org's New ESO study evaluates impact of satellite constellations on ...
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Scattered Intensity of Light vs Angles of Incidence and Emission
So I just derived an expression for the scattered intensity of light from an atmosphere with ideal isotopic scattering: $I/F=\frac{cos(i)}{4(cos(e)+cos(i))}$, where $I$ is intensity, $F$ is flux, $i$ ...
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Solar eclipse impact on twilight
Has anyone observed the impact of the solar eclipse on twilight? I mean mostly the extension of the totality path in the atmosphere.
I mean the pattern below:
I - normal situation with total solar ...
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What are the oxygen or water vapor lines?
I was reading the document Recommendation ITU-R P.676-11 (09/2016); Attenuation by atmospheric gases (P Series, Radiowave propagation) in order to calculate the atmospheric losses, and there were some ...
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Why could I so easily see and photograph such a bright totally eclipsed Moon from a bright city road? (May 26, 2021 total lunar eclipse)
Due to scheduling and geometry I could only snap last night's lunar eclipse with an older model cell phone on a pedestrian overpass of a brightly lit city street, but surprisingly the Moon was quite ...
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How far can we detect lightning in radioastronomy?
The wikipedia article on whistlers has this information:
Voyager 1 and 2 spacecraft detected whistler-like activity in the
vicinity of Jupiter known as "Jovian Whistlers", implying the ...
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Why would atmospheric absorption increase rather than decrease the antenna temperature in Penzias and Wilson's famous CMB observation?
The classic paper A MEASUREMENT OF EXCESS ANTENNA TEMPERATURE AT 4080 Mc/s begins:
Measurements of the effective zenith noise temperature of the 20-foot horn-reflector antenna (Crawford, Hogg, and ...
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