Questions tagged [planetary-science]

The study of planets, asteroids, comets, etc, including weather, geology, composition, etc. This tag should be used when the focus of the question is on the the science of a non-Earth non-star natural object, and not used when designing spacecraft to cope with said challenges.

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How to make diamagnetic lunar simulant that would "float" in a strong enough magnetic field? (for China's 60 cm high field simulator)

Live Science's China builds 'artificial moon' for gravity experiment says: Chinese scientists have built an "artificial moon" research facility that will enable them to simulate low-gravity ...
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Fjeldbo, Kliore, & Eshleman 1971 Fig. 22 planetary atmosphere index of refraction increasing with altitude; physics insight or convenient abstraction?

this answer to Is it possible for a spacecraft to communicate with Earth when a planet is in the way? suggesting that atmospheric refraction could be used to get at least some kind of signal around a ...
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Just how locked is Titan? Does it exhibit libration due to eccentricity? Have residual oscillations not yet damped out been detected or ruled out?

Under Where is the Selk crater on Titan with respect to Saturn? there is @BrendanLuke15's comment which provides a helpful hint: Tidally locked moons have their 0° longitude defined as the 'sub-...
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Could and should not the search for the location(s) of the Martian methane spikes become the main scientific objective for the Curiosity rover?

In Nature Geoscience's article Independent confirmation of a methane spike on Mars and a source region east of Gale Crater is announced that the reported methane spike on sol 305 by the Tunable Laser ...
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Where are the meteorite remnants related to the craters they've produced on the moon?

On Earth, in every crater there's usually at least some remnant of a meteorite. But with all the craters on the Moon, where are the meteorites in the middle of them?
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Just how steep are Pluto's tallest ice mountains?

This answer to How tall are Pluto's mountains? Are they the tallest ice features in the Solar System? is worth a read and an upvote and says they are upwards of 3,500 meters and most likely water ice! ...
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Can "prolateness" be characterized by a $J_2$ coefficient like "oblateness"?

When an imperfect sphere can be obtained by rotating an ellipse around an axis, it is called a spheroid. There are two types of spheroids, oblate ones and prolate ones. Most solar bodies can be ...
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What kind of experiments would a scientist do on Mars?

If we have people on Mars around 20, 25 years from now, what kind of scientific study would they be doing on a daily basis? I know places we'd want to study, places where ancient water flows might ...
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Agriculture on an exoplanet

If we find a hypothetical Earth-like planet A with a rocky terrain that we could colonize, how would we go about planting the first plants, knowing that there is a deficient of nutrients and the ...
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How does the wind behave throughout the day in Jezero Crater? (worried about Ingenuity)

JPL tweet links to mars.nasa.gov's Flying on Mars Is Getting Harder and Harder which explains that seasonal changes are lowering the density of the local atmosphere, presumably due to warmer seasonal ...
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Impact Venus with Comet Leonard?

do we have the means to slightly alter Comet Leonard's trajectory so it impacts Venus instead of 'grazing' it in December 2021??
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How are astronauts aboard the Tiangong space station keeping busy?

Per Wikipedia's Tiangong space station viewed today: Days in orbit: 3 months, 15 days (13 August 2021) Days occupied: 1 month, 27 days (13 August 2021) Currently it is just the single core ...
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Has opalescence ever been observed on any solar system body besides Earth? Or at least from a sample from one?

New method for exoplanet detection based on iridescence? in Astronomy SE asks about observations of exoplanets, but here I'm asking about our own solar system bodies. Question: Has opalescence ever ...
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Has iridescence ever been observed on any solar system body besides Earth? Or at least from a sample from one?

New method for exoplanet detection based on iridescence? in Astronomy SE asks about observations of exoplanets, but here I'm asking about our own solar system bodies. Question: Has iridescence ever ...
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Perseverance's First Borehole looks like its particles of sand stuck together by something; composition of this material and source of adhesion?

Resampled and sharpened detail from PIA24796: WATSON Image of Perseverance's First Borehole This is reminiscent of a day at the beach digging a hole in wet sand. The walls remain standing as long as ...
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DAWN CERES HAMO CYCLE1 PDS DATA ARCHIVE seems to be corrupted

I'm working on Ceres VIR_IR data from PDS3 Archive. The downloaded data seems to not be right as I'm getting lines of various colors and not the target area, when opened in ENVI. Is the QUB file ...
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Is there believed to be sharp boundary between Jupiter's liquid and metallic hydrogen layers and is there much convection and flow between them?

If it's not known, is it reasonable to assume that some Jupiter-like exoplanets might have well separated liquid and metallic hydrogen layers given moderately different temperature and mass? Author: ...
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Habitable rocky exoplanet with radius 2 times of Earth but similar surface gravity

Planet Earth has radius 2x of planet Mars, while having 10x times of Mars mass and 60% higher surface gravity. Could there exist rocky exoplanet with 2x radius of Earth but similar surface gravity (+-...
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How does ECOSTRESS measure both temperature and emissivity of the Earth's surface simultaneously? (Science package aboard the ISS)

The This Week at NASA video A U.S. Commercial Spacecraft Departs the Space Station on This Week @NASA – July 2, 2021 includes the following quote: Data from NASA’s Ecosystem Spaceborne Thermal ...
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How do they know the sub-surface radar reflections (potential underground ice or "lakes") on Mars are not natural dielectric or metallic in origin?

Gizmodo's NASA Scientists Find More Subsurface Lakes on Mars links to Characteristics of the Basal Interface of the Martian South Polar Layered Deposits (paywalled, but there is this 52nd Lunar and ...
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How does Curiosity's X-ray diffractometer work? Does it measure only one angle at a time or does it have an area detector?

Per this answer to Are quasicrystals common on the Moon and Mars?, Curiosity has an X-ray diffractometer. X-ray diffraction from 3D crystals can (begin to) be understood by embracing Bragg's law. A 3D ...
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Plot of the thermally-induced tilt in Martian surface during solar eclipse by Phobos? (slope of 1 atom per meter?)

Space.com's Mars lander InSight picks up tiny ground tilt caused by Phobos moon transit says that both Insight's ultra-sensitive seismometer picked up a very tiny transient shift in attitude during a ...
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Is Geothermal Cooling on Venus Possible?

Would geothermal type cooling be possible for a stationary base on the surface of Venus? Would the subsoil temperature of Venus hotter or cooler than the atmospheric temperature? (464C / 867F average ...
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When do Mars, Venus and Earth Align?

I found that all planets in the solar system align on 6 May 2492. How can I find when Mars, Venus and Earth align? Perhaps it is sooner.
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Why is the Southern Hemisphere of Mars is heavily struck by asteroids while the northern part is relatively smooth?

The northern hemisphere of Mars is smooth with flats lands but areas particularly below the Tharsis rise is heavily cratered, also Hellas basin, one of the largest impact craters is located in the ...
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Could the phosphorus in phosphine in the Venus atmosphere probably produced by cosmic ray spallation of sulfur? [closed]

Reading the following questions and their answers: Why wasn't the phosphine in Venus' atmosphere detected by space probes? Phosphine, yes -- but where are the organic compounds on Venus? the ...
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Has any rover dragged a magnet across martian soil to see what gets picked up? Any magnetic measurements of specific rocks or particles of any kind?

On Earth, amateur and sometimes professional scientists collect dust from the tops of buildings or mountians (see also) and separate it with a magnet to obtain meteoric material. Not all meteoric ...
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If we could manipulate the orbits of bodies, how big of an object would be needed to impact Venus to create a moon?

https://en.m.wikipedia.org/wiki/Giant-impact_hypothesis The Giant Impact hypothesis for our own Moon explains not only our Moon but how our molten mantle got "stirred" enough to create our ...
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Did Chang'e-3 and/or Yutu report getting hit by the Earth's magnetotail?

@DavidHammen's answer to If a solar flare happened during a total lunar eclipse, would the Earth block the flare from hitting the moon? And for how long? describes the regular lashing of the Moon by ...
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How do they measure the voltage of the Moon?

@DavidHammen's answer to If a solar flare happened during a total lunar eclipse, would the Earth block the flare from hitting the moon? And for how long? describes the regular lashing of the Moon by ...
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Difference between "mafic floor" and "olivine-bearing floor" in Jezero crater? (Perseverance landing site)

Figure 3: Main geologic units within Jezero crater shown on a basemap constructed from images from the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance ...
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Why Perseverance's landing ellipse straddled the cliffs in the river delta; why so ambivalent about the two different geologies?

The Perseverance landing site has now been named for Octavia E. Butler and from here there will be a meandering climb to get up on top of the "cliffs" that are in the delta. I think that ...
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How to convert to GEO cordinate from the Mars Solar orbital coordinate (Sun-state)

I am working on the planetary science (on Mars) project for my master thesis. I am using MAVEN data for analysis. Data (spacecraft position) are measured in MSO (Mars Solar orbital) coordinate. I ...
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How many planets have had their limbs scanned with radio signals?

This answer to When did planetary scientists realize Venus' surface pressure was almost 100x that on Earth? How did they find out? describes one example of scanning the limb of a planet using ...
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Would the >100 km "knee" in Earth's atmosphere still be where MFP exceeded scale height if it were pure Ne or Ar?

There is currently one answer to How many solar system bodies have "knees" in their atmospheres? that points out that somewhere above roughly 100 km turbulent mixing drops off (thus the name ...
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How many solar system bodies have "knees" in their atmospheres?

Discussion lead to citing Why does Earth's atmospheric density have a big "knee" around 100 km? Is there a good analytical approximation? who's answer is "monatomic oxygen". ...
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Surface processes of the valleys on Mars

I have two related questions about geophysical processes related to talus* fans on Mars: How were talus fans on Mars formed? (like Valles Marineris or Kasei Valles) What is the role of these fans or ...
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Could we intentionally contaminate another celestial body with life to start producing oxygen?

My question is simple, could we "nuke" a planet with life to create an atmosphere over time? I was seeing a documentary about Jupiter's moon, Europa, and how it could have hydro thermal ...
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Can VLF be used to create a Mars barrier?

I just ran across some older articles in 2017 discussing how VLF radio waves created an artificial barrier to space weather. Basically how VLF improves Earth’s protection from solar radiation. This ...
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The Surface of Mars

There are surface features on Mars that we can observe with remote sensing data. There are many shorelines seen in a way. Despite its subtle atmosphere or storms, these surface features remain. How do ...
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Which of the four inner planets has the strongest magnetic field, Mars, Mercury, Venus, or Earth?

Which of the four terrestrial planets has the strongest magnetic field, Mars, Mercury, Venus, or Earth?
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Do other planets and moons share Earth’s mineral diversity?

Earth is full of different minerals. Each patch of land, between plate tectonics and other forces, finds itself brimming with a variety of interesting and more importantly, different, minerals. Does ...
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When and where on Planet Mars are the Sun's rays the most blueshifted?

Let's say for a moment that the spin of a planet causes the Sun's rays to be blue-shifted in the morning. As far as I know, redshift occurs in steps of like 2.6 km/s or something like that. We can't ...
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How to determine the distance between Olympus Mons and Valles Marineris?

How can I determine the distance between Olympus Mons and the closest point of Valles Marineris? What tools are available to the general public for these kinds of queries?
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How hard is the hardest ice in the solar system? Is it in Pluto's ice mountains?

NPR's Pluto Has White-Capped Mountains, But Not Because There's Snow includes the following: "Initially, it seemed logical that this high-altitude frost could form like on the Earth," says ...
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Is Mohs scale of mineral hardness applicable for rocks and minerals of terrestrial planets other than Earth?

The Mohs scale of mineral hardness is a qualitative ordinal scale characterizing scratch resistance of various minerals through the ability of harder material to scratch softer material. Now there is ...
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Updating of TAI

In spaceflight keeping track of time between systems widely separated in space (e.g. people on Earth vs spacecraft in deep space) and/or time, moving at substantial relative velocities and in ...
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Is the surface environment of Venus corrosive?

Venus famously has clouds of concentrated sulfuric acid in its upper atmosphere. Frequently I will see posts here citing the acidity of the atmosphere as a challenge to probes on the surface (such as &...
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What is "Planetary Defense", and what are the threats one can potentially defend against?

The planetary-defense tag has the current (my) awkwardly-written description. related to the defense of a planet from a major destructive event such as an impact, or searches for or studies of ...
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Obtaining Europa's samples from Callisto. Possible to identify them? Worthwhile?

A lot has been discussed about the possibility of panspermia between Earth and Mars, and how compact systems such as Trappist-1 can be more prone to that. Here on Earth, we have identified numerous ...

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