Questions tagged [planetary-atmosphere]

Atmospheres of planets, moons, and other solar system bodies excluding stars. For those, use "stellar-atmosphere" instead. For influences of Earth's atmosphere on astronomical observations use "atmospheric-effects". For other questions about the Earth's atmosphere, Earth Science SE is probably the right site. https://earthscience.stackexchange.com/

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How might a lower gravity planet sustain a warm, earth-like atmosphere?

I'm designing a hypothetical lower-gravity planet with 0.47M, 0.79r and 0.76g, with a similar density to Earth. I've already determined that this mass, radius, and density will allow my planet to ...
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Why aren't there sulfuric acid seas on Venus?

It's commonly known that sulfuric acid rain doesn't reach Venus' surface. It evaporates instead because the surface it too hot. But considering how high the pressure at the surface (9.3 MPa), shouldn'...
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How to model the kinematics of gases expelled from comets and planetary atmospheres?

Once the ices of comets sublimate, where do they move to, and with which equations do you describe their motion in the interplanetary medium? Similarly, where do the gases that are stripped from the ...
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What are the scale heights of the atmospheres of the Solar System worlds?

What causes the relative scale heights of the atmospheres in the Solar System? In various scientific contexts, a scale height, usually denoted by the capital letter H, is a distance over which a ...
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Is the gas in a planet forming disk around a star comparable in density to an atmosphere?

If you were standing on a planetesimal in the planet forming disk of a new solar system (or our own, billions of years ago), would you be able to feel "interplanetary wind"? Would it be ...
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How un-dense can a terrestrial planet get before it turns into a mini-Neptune?

EDIT: well, now I have more For reference: A terrestrial planet is a planet that is made out of silicates and metals. A Mini-Neptune is, as far as I know, the smallest type of giant planet (arguably,...
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Can a planet with no atmosphere be orbited at extremely low altitudes?

Can a planet that has absolutely no atmosphere be orbited by a spacecraft at extremely low "altitudes" (if you'd even call it altitude at such a low orbit. For instance, if this planet's ...
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Titan's Atmosphere

Is Titan's atmosphere being continually regenerated? What is the current thinking on the origins and maintenance of Titan's atmosphere after the landing of the Huygens probe. As I remember, ...
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Would lightning on planets with noble gas rich atmospheres cause a glow similar to an electric discharge lamp?

I've read about how noble gases in gas tubes emit varying colors of light when electricity is passed through them For a planet with noble gas rich atmospheres (say >20%), would a lightning strike ...
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Are planets far from their parent star more likely or less likely to have an atmosphere?

Are non-gaseous planets (e.g. super-Earths) that are either rogue or very far from their parent star(s) less likely or more likely to have a significant atmosphere? On one hand planets closer to their ...
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If the sky is the limit...where does the sky start? [closed]

Does the "sky" start anywhere that the land is not touching? Does it start after the troposphere? After the atmosphere?
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Up to what distance from the Moon does the Moon's gravity hold its exosphere before it is being cast away by solar wind?

Up to how far from the Moon is the Moon's exosphere gravitationally bound to it? For the Earth's exosphere it is 120,000 mi (190,000 km) or half the Moon's distance from the Earth, beyond that the ...
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When will Jezero crater on Mars reach its lowest atmospheric pressure and what pressure will that be?

In the first sols of the Mars 2020 mission the local pressure was something above 750 Pa. It has been decaying since then and is now less than 650 Pa, this is what required Ingenuity's rotorblades to ...
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How would the surface of Mars compare with the Atacama desert for millimeter wave (and shorter) radio astronomy?

In this answer to What kind of experiments would a scientist do on Mars? I suggest that the resemblance of the ALMA array's site in the Atacama Desert to the surface of Mars suggests millimeter ...
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Which Venus scientists discovered the hole in the ozone layer?

After 21:00 in Venus: Earth’s Evil Twin or Just Misunderstood? (live public talk) from the JPL YouTube channel the person being interviewed "Sue Smrekar, Rocky ...
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How does the Hubble Space Telescope measure the speed of the wind inside Jupiter's Great Red Spot?

Space.com's Jupiter's winds of change show increased storm speeds in Great Red Spot and Hubblesite.org's Hubble Shows Winds in Jupiter's Great Red Spot are Speeding Up both link to the recent open ...
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Would tidally locked Earth-like exoplanets necessarily have hot pole/cold pole atmospheric circulation?

A tidally locked planet orbiting a red dwarf star in its habitable zone would have a rotational period equal to its orbital period, on the order of days or weeks. Given a thick enough atmosphere ...
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Maximum distance at which planetary atmospheres can be analyzed during transits?

Is there a limit for how far away you could make a spectroscopic analysis of a planet when it transits its star, to detect bio markers and industry markers? What would the limit be with current ...
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At what point does an astronomical body's surface stop being gas giant-like and start being sun-like?

I've generally seen brown dwarfs depicted as more massive and slightly wider Jupiters in varying colors with banded cloud structures, sometimes hot enough to be visible glowing. I've also seen red ...
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...but where did Mars' atmosphere actually GO?

In this answer to How is space a vacuum when there are planets, gases, etc? I mention that most of Mars' original atmosphere was swept away by the solar wind after the planet lost its magnetic field ...
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What discoveries were made thanks to Pioneer orbiter data?

Based on the Wikipedia page Pioneer Venus Orbiter (also known as Pioneer Venus 1, Pioneer 12, 1978-051A) there were quite a few scientific instruments on board. But what scientific results were ...
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What if you lit a fire on a planet whose atmosphere consists of 50% oxygen and 50% a flammable gas?

If a planet's atmosphere consisted of 50% oxygen and 50% a flammable gas (e.g. methane) at 1 atm, could you put the entire atmosphere on fire by lighting a single candle?
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How can we count layers of atmosphere? [closed]

How can we count layers of atmosphere even though there are no lines or boundaries which separate atmosphere?
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Were K2-141b and WASP-63b selected as the first two exoplanet atmospheres for JWST to look at during its first year of observations? If so, why?

In The Observatory @Donald.McLean linked to Scientists will peer at first galaxies with James Webb telescope which says in part: The new telescope will augment science performed by Hubble, not ...
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Tidally locked Venus, is it possible and consequences?

Suppose, Venus becomes tidally locked. Will its dark side cool enough so that the CO2 from the atmosphere to precipitate in liquid form to make an ocean? Also, I wonder, how close Venus is to becoming ...
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Where should I look at if I had a 25m parabolic radio reflector?

I am most interested in (exo)planets with atmospheres, see e.g. my question Requirements to resolve position of Jovian Whistlers up to magnitude of Red Spot with amateur radio equipment? So if I had ...
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Is there a link between the amount of swirling and vorticity in a gas giant's atmosphere and its distance to its Sun?

This is an empirical observation of mine: I have noticed that out of the 4 gas giants in our Solar System, Jupiter's atmosphere has the most visible swirls and complex cloud patterns, followed by ...
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What is the Milne-Eddington Approximation?

In this paper: Planet temperatures with surface cooling parameterized it states in the "radiation model" the following: The Eddington–Milne approximation relates $T_0$ and $T_e$ through the ...
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How much more mass would Mars need to currently have enough pressure for liquid water and oxygen?

My question is whether Mars just about failed to meet the threshold or missed it by a lot. It's been dry for 3 billion years. How much bigger would it have needed to be to buy it that extra time? Let'...
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Earlier references of Mars' arsia mons elongated cloud?

The weird long cloud on Mars is finally revealing some of its secrets is an article by Chelsea Gohd from space.com referencing ESA's Mars Express news. The Arisa Mons Elongated Cloud (AMEC) is ...
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When examining an exoplanet's atmosphere is the star's emission spectra or planet's light used?

My understanding of the main method we use to figure out an exoplanet atmosphere composition is that when a exoplanet transits their sun, visible light passes through the planet's atmosphere, and ...
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What is the underlying nature of the dark spot found on Uranus?

What is the nature of bright spots found on Uranus? actually quotes Space.com's Uranus Has a Dark Spot which says: During the past decade, many bright spots have been seen on Uranus in both red and ...
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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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Did the Moon have a substantial atmosphere in the past?

The layer of gas surrounding the Moon is very thin. It is a surface bound exosphere, where particle-particle collisions are rare. In the past, the Moon was more geologically active, with eruptions ...
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What replenishes the lunar atmosphere?

It is often said that the Moon doesn't have an atmosphere. But there is an envelope of gas surrounding the Moon, albeit a thin one, so the Moon has at least an exosphere. The Moon doesn't have its own ...
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What does the amino acid found in the atmosphere of Venus mean?

An amino acid is a part of DNA, but it has only been found on Earth. Is the amino acid maybe from one of the space vehicles that has orbited, scanned, or surveyed Venus? How can a part of DNA survive ...
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Extraterrestrial snow?

What do we know about extraterrestrial snow? On which (exo)planets or (exo)moons do we have direct hints for its existance? This is indeed a children's question, but I struggle to answer it ...
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Have auroras on Titan been observed yet?

After reading the very insightful introduction to auroras on other planets I started digging and found various questions and some answers here on the same topic, see below. What I did not figure out ...
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Characteristics of Venus' jet streams?

Since the Voyager missions, the atmosphere of Jupiter received great attention, its jet streams made it into text books on geofluid mechanics, including their characteristics like the how they meander,...
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How do we get to know the total mass of an atmosphere?

Since atmospheres don't end abruptly but gradually get thinner the higher you go, I wonder how we can get the total mass of an atmosphere if we don't know where exactly it ends. E.g. the Earth's ...
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Does lightning on Venus affect the chemical composition of the clouds?

It is established that lightning occurs on Venus due to the presence of sulfuric acid clouds. Does this constant electric discharges and possible electrolysis affects the composition of the clouds on ...
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Do brown dwarfs have stripes?

Brown dwarfs (BD) are often depicted with stripes. brown dwarf Jupiter Pictures of BD resemble Jupiter but brown dwarfs ...
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What is the nature of bright spots found on Uranus?

The following text is from space.com which was written during the time of discovery of the first dark spot on Uranus: During the past decade, many bright spots have been seen on Uranus in both red ...
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Can the Sudarsky's gas giant classification be applied to ice giants?

Based on the temperature of a gas giant around another star, I have come to understand that it is possible to guestimate its appearance; a classification scheme for gas giants developed by David ...
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How are sulfuric acid clouds able to completely cover Venus?

It is a well-known fact that an opaque layer of highly reflective clouds of sulfuric acid completely shrouds Venus preventing its surface from being seen from space in visible light. This is mentioned ...
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If water vapor is always blown away into space, how is it able to create chemical compounds on Venus?

This is the follow-up of this chem.SE question. According to Wikipedia, water vapor on Venus is present in trace amount (20 ppm). There are multiple reasons why Venus has very low water content: The ...
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What other hints of possible life in Venusian atmosphere have we dismissed?

Now that phosphine has probably been discovered in relatively large quantities in the Venusian atmosphere, I heard that there have been other unexplained phenomena (i.e. dark patches) seen. Does ...
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Is dust the only reason why the Martian sky is so bright?

The atmospheric pressure on the surface of Mars is 0.00609 atm on average and 0.012 atm at most in the Hellas Basin. On Earth, at these pressures, which are found at altitudes about 30-35 km (19-22 mi)...
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Can concentration of gas in exoplanet atmosphere be found out from wavelength and absorbing radius from spectral data?

I was working on exoplanet spectral data from which I need to infer the concentration of gases. However, the exoplanet spectroscopy data contains only absorption wavelength and absorption radius. Is ...
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What is the difference between aurorae and electroglow?

One of the discoveries of Voyager 2 at Uranus was a phenomenon called "electroglow", which as I understand it is related to charged particles interacting with the atmosphere that cause the ...
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