Questions tagged [planetary-science]
The planetary-science tag has no usage guidance.
137 questions
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A planet after a moon-generating impact
Nascent terrestrial planets quickly have their surfaces cool down.
Formation of crust then yields formation of a figure.
What happens to the already formed crust and the figure after an energetic ...
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Why is the rotation period of regular moons in sync with the orbit period? What is the evidentiary support for tidal lock? [duplicate]
NOTES FOR CLARIFICATION: I am asking for actual evidence, not theories. E.g. If a theory says that they tidal lock takes x million years, what evidence shows they were not locked before that time? ...
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Can astronomical objects repel other bodies if they have a sufficiently strong magnetic field?
I was wondering whether an astronomical object (a planet, a star, a neutron star, a magnetar...) with a sufficiently strong magnetic field could repel another object (like a planet, an asteroid...), ...
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How to define "Earth" so that it is almost 50% oxygen by weight?
In this comment, Astronomy SE community member David S. writes:
Just an FYI, Earth is almost 50% oxygen by weight.
How, specifically, is "Earth" defined to make this statement correct?
(Or,...
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How can ultraviolet planetary images help us in research?
Recently I was browsing through Ultraviolet images clicked by Cassini, Galileo and Hubble Space Telescope on OPUS and though they all seemed quite attractive, I couldn't quite figure out what all ...
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Are there any specific examples of overlapping impact and volcanic craters on astronomical bodies beyond Earth?
This answer to Can a crater form inside another crater points out that in addition to impact-on-impact double craters there can be volcanic double craters, and even a one on the other (though no ...
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Which of the blocked radiation windows will (mostly) open if one where to observe from the surface of Mars, instead of the Earth?
Earth’s atmosphere is composed of about 78 percent nitrogen, 21 percent oxygen, 0.9 percent argon, and 0.1 percent other gases. Trace amounts of carbon dioxide, methane, water vapor, and neon are some ...
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What are the odds of a planet with an eclipse every time the moon rotated around the planet?
If the orbital plane of a planet and its moon were sufficiently aligned, the moon could cause a solar eclipse every lunar month. What are the odds of that happening? To answer, I would guess that one ...
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What will it take to start measuring the rotation rate and direction of exoplanets? Which instrument(s) current or future are most likely to do it?
@ProfRob's answer to Is it coincidence that the earth's rotation and revolution are in the same direction? explains several important aspects of models for planetary formation, angular momentum and ...
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How can I calculate current position of planet in sky
How can I calculate current position of planet in sky from earth's point of view. I want to calculate based on given DATETIME and Location
For example, if I see current position of planets on "23 ...
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Why is it impossible to infer the surface temperature of Venus by spectroscopy observation from earth?
It is well known that the surface temperature of the sun is determined by fitting the sunlight with the black-body spectrum.
Why is this inappropriate for Venus?
I have the question because of the ...
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Calculating the absolute magnitude of a solar system body
I am trying to calculate the absolute magnitude of a solar system object, given its albedo, and assuming all of its luminosity comes from reflecting light from the sun. Using $L_{sun}$ = solar ...
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Is an earth-sized moon orbiting a super-earth feasible?
Is an earth-sized moon orbiting a super-earth feasible?
Or would tidal forces say 'no thanks'?
I'm making a system for the Kerbal Space Program Kopernicus mod and am trying to make it as realistic as ...
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Why would rocky earth-like planets be rare around white dwarf stars?
I came upon an article here https://phys.org/news/2023-11-white-dwarfs-life-planets.html
The author thinks that rocky earth-like planets could be rare around white dwarfs.What could be the reason for ...
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What happens to a binary star system when one of the stars explodes and loses a lot of mass
If one star of a binary system explodes and leaves a remnant. The remnant would still have the velocity but lack the mass of the original star.
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How is a Planet's Moment of Inertia Measured Remotely?
In the July 2023 issue of Sky & Telescope there is an article titled Sights Set on Uranus. In that article the following statement is made:
Since the 1930's we've suspected that Uranus and ...
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Clarifications on Planetary Magnetic Fields
I believe I understand this equation for the dynamo effect of planets as far as iron-nickel cores go, where ρ is density in kilograms per cubic meter, Ω is rotation speed in radians per second, σ is ...
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When analyzing a particle moving at Kepler speed, √(GM/R) in a planetary magnetic field, do we need to convert it to angular speed, √(GM/R^3)?
A charged particle is moving in a planetary magnetic field, in a spherical polar coordinates which is corotating with the magnetic field. To solve the equations of motion numerically what would be the ...
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Is the magnetic permeability (mu_0) necessary in the expression for planetary magnetic field?
To numerically analyse the Lorentz effect due to the magnetic field, say, radial component on a charge particles which of the expression would be correct, $\{ B_r = \frac{2R}{r^3} g_1^0 \cos(\theta) \}...
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Why is Uranus called a "green planet"?
Uranus is called a green planet, although it appears blue in many of the photographs including those taken by spacecraft, like Voyager 2, Hubble, and JWST. NASA's Uranus page mentions it to be bluish-...
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What secondary and tertiary conclusions can be drawn from the temperature characteristics of lunar soil sent by ISRO Chandrayaan 3?
ISRO Chandrayaan 3 released the following data today about the temperature characteristics of lunar soil.
What secondary and tertiary conclusions can be drawn it?
More specifically, what may be the ...
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Under which conditions could a planet's massive moon's orbit get closer to the planet?
The recent question How do we know the Moon was much closer than it is now? has piqued my interest. The answers are numerous and clear. But I started to wonder. The question includes the following ...
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Does rotation on their axis cause winds in gaseous planets?
As far as I know, as planets rotate around their axis, they can influence winds but not cause them (like the Coriolis effect)
However, does this apply only for rocky planets? Do rotation alone in ...
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Looking for a Specific Planet
I know my title isn't the most specific, but the planet I am looking for is. I have been looking through many exoplanets and I can't seem to find what I am looking for, the closest I have found is ...
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Concerning a binary system of stars/planets/black holes could one of them be ejected before eventually merging or colliding?
I was having a discussion with an undergraduate student of physics about binaries and their interactions with external celestial bodies (which could cause the ejection of one of the members in the ...
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Are there any softwares which help in simulating different experiments regarding flight of aircrafts on different terrestrial planets of solar system?
I have a few experiments on aircrafts whose results I am aware of if performed on the earth's surface. However, I am searching for software(s) that can help simulate the same or other experiments on ...
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Will all satellites get inevitably tidally locked to their planet?
Are there cases or conditions in which an object orbiting another one (e.g. a satellite and its planet) does not get tidally locked to it?
For example, in this question, it is mentioned that a large ...
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how big would an asteroid have to be to leave a crater on Earth
if an asteroid were to hit earth, how big would it have to be to make a crater and not just vaporise in the atmosphere?
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Could rogue planets with cold nucleus have winds or water currents/waves due to the planet's rotation?
Are there any types of wind or waves caused and produced only and exclusively by a planet's rotation? Not influenced by the planet's rotation, but produced solely by it?
In the case of waves, are ...
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To what extent does the increased average airmass the Sun's light passes through contribute to the seasons?
The traditional explanation for the cause of seasons I have heard is that because of the angle of the axis of the Earth with respect to the ecliptic, the angle at which light rays hit the Earth's ...
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If phosphine gas is to be proof of life on a planet, shouldn't there be other gases too?
If microbes on Venus produce phosphine, wouldn't there also be other gases produced by microbes since earth has many kinds of bacteria and the fast reproduction rate of bacteria make genetic mutations ...
user50918
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Does the Drake equation consider how far a planet must be from gamma ray bursters, black holes supernovae etc for life to survive?
Can we use these dangerous phenomena to predict where life can't exist?
user50918
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What are radio frequencies sensitive to in galaxies?
Apart from 21cm line studies, radio emissions as well as signatures of different radio sources, do radio frequencies help in the identification of a particular physical structure or presence of some ...
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Where can I get raw photos of planets clicked by HST, Voyager 1 and 2, Cassini for Saturn and Galileo for Jupiter?
I intend to process RAW images of planets clicked by HST,Voyager 1 and 2, Cassini and Gallileo spacecrafts using a few softwares.
I am in search of where I can get these raw images from.
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What do chthonian planets look like?
Obviously, a chthonian is going to be hot, but what colours could it have? What would the surface composition be? Would it keep patterns from the gas-bands it used to have, or would those have been ...
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Conversion of 1D plot in 3D plot gives different physics
I am to track the path of a particle due to Lorentz force of the planet magnetic field, assuming there is no gravitational force on it.
The equation of motion due to Lorentz force in rotating ...
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"And in some cases, a (free floating) planet (FFP) can form on its own outside of any solar system." Cool! But what are those cases?
The April 2, 2023 Inverse article 9 Years Ago, Astronomers Found Two Rogue Planets — But They Didn’t Realize It Until Now says:
Planets are typically part of a planetary system and are ...
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Numerical Programming using ODEINT takes more than 17 minutes
I am trying to track the trajectories of a charged particles under the influence of Gravitational and Electromagnetic effect. Computing for time points, t0=0second -tf= (36002430)sec with stepsize 0....
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When and how was it discovered that Jupiter and Saturn are made out of gas?
Was it due to appearance only or spectroscopic methods were used? Venus also has a thick cloud cover, how was it determined to be a rocky planet?
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What caused the “rake marks” in moon photos?
A conspiracy theorist on Facebook claimed photos from the moon show “rake marks” in the lunar soil. You have to zoom in and look very hard, but I do see a faint pattern of light-colored lines going ...
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Can a tidally locked planet sustain a magnetic field
The vast majority of stars in the Galaxy, and probably the universe, are red dwarfs. The habitable zones of these stars are very close to the stars themselves, often within what would be Mercury’s ...
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Do humans have the capacity to blow up the entire planet earth today? [closed]
For example, if we are able to gather all the available nuclear weapons in place and target towards a weak point, say an earthquake fault line, will the entire planet be blown to bits?
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Effects of other planets on life on Earth
I've heard this often in the media, that the gas planet Jupiter has a significant effect upon life on Earth - by, the say, drawing asteroids & comets to itself, many planet-killer are destroyed as ...
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Do conjunctions of planets block out the sun and cause measurable cooling of the atmosphere on one of the planets?
Is a significant amount of light energy blocked by one planet such that there is noticeable cooling of the atmosphere of another?
user48394
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What are these bumps on Europa?
The surface of Europa is famous for all the criss-cross lines thought to be cracks in the ice above a water ocean that somehow re-freeze.
But in the photo below I also see a lot of raised "bumps&...
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How could we detect if Venus or mars were being terraformed by aliens? [closed]
If any other body in our solar system was being terraformed by aliens, what would be the ways in which we would detect this?
Initially I thought of Venus or mars but I guess this could extend to any ...
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Radio signals between Mercury and the Moon during an eclipse
This is a hypothetical question. Thank you for your time and efforts.
A signal is sent from a transmitter on Mercury's surface while it is at its greatest western or eastern elongation. The signal is ...
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Does polar motion cause the Earth ellipsoid to change?
The Earth is oblate because it spins and is not a rigid body. Since its spin axis changes relative to its crust, then the meridian of maximum diameter changes too, right?
I understand that polar ...
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In which Indian Institutions can I find Planetary Scientists or Planetary Geologists? [closed]
Which institutions in India provide labs and facilities for research in the field of Planetary Sciences/Planetary Geology?
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If 16 million kilometers were added to Earth's semi-major axis, what measurable effect would there be on Mars' orbit?
I have some education in astronomy, but nothing extensive in astrophysics. I can follow mathematical procedure with assistance. Procedural responses are most welcome!
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