Questions tagged [geology]

Questions related to processes and principles related to the interior and the solid surface of a planetary body.

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What are the effects of mass concentration along a planet's axis of rotation?

Reading about geological history of Mars and coming across the Martian dichotomy, which is about having the two hemispheres' geography differ in elevation by 1 to 3 km. Does this mean that Mars' ...
jkztd's user avatar
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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 ...
spaceman0x2A's user avatar
0 votes
1 answer
196 views

Why don't scientists believe Earth's surface water came up from the mantle?

I read, periodically, that there is more water trapped in the mantle than there is in the oceans - possibly a lot more. If so, why don't any geologists believe that Earth's surface and near-surface ...
Kurt Hikes's user avatar
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Geological/tectonic/thermal/etc. implications of Rayleigh numbers ≥ 100,000,000

What's a Rayleigh number? Well, it doesn't have anything to do with Rayleigh scattering. Here's a Wikipedia page on this concept, but I believe Elvira Mulyukova's and David Bercovici's Mantle ...
KEY_ABRADE's user avatar
2 votes
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Are stagnant-lid Earth analogues guaranteed to become Venus-like?

In our current understanding of Venus, two things are generally accepted: Venus reached its thermal tipping point at least 700 Ma. As the Sun's luminosity gradually increased with age, its average ...
Thoth's user avatar
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What is the elevation of this mesa in Noctis Labyrinthus?

I'm interested in the elevation of this mesa in Noctis Labyrinthus. It's located at -6.3, 265. This image is from https://www.geo.fu-berlin.de/en/geol/fachrichtungen/planet/press/archiv2016/...
Sam Ruhmkorff's user avatar
1 vote
1 answer
102 views

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?
Dhruv Nayak's user avatar
6 votes
1 answer
248 views

What value of density would a planet need to be classified as 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,...
KEY_ABRADE's user avatar
3 votes
1 answer
131 views

How did the mountain range form in Galle crater?

In the Galle crater, there is a mountain range that is shaped like a circle segment that makes it look like a smiley face. How did this mountain range form? Is it a central ring that formed with the ...
usernumber's user avatar
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Are there any mountains/volcanoes steeper than Tharsis Tholus?

Although Olympus Mons is the tallest mountain in the solar system, its slope is so gradual that the peak cannot be seen from the plain; it is hidden by the planet's curvature (flank slope = 5.2°). The ...
Nilay Ghosh's user avatar
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Was the young Sun cooler or hotter than it is today?

Generally, astrophysicists say that the young Sun was only about 70% as warm as today, which leads to the alleged 'Faint young Sun paradox' about how a young Earth could have been as warm as it (again,...
Kurt Hikes's user avatar
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Why do Venus, Earth, and Mars have tall volcanoes, but the Moon, Mercury, and Io don't?

There are numerous examples of multi-kilometre tall mountains such as Maat mons on Venus, Mauna Kea on Earth, the Tharsis volcanoes on Mars. We don't find similar such examples of volcanic edifices ...
we'll see's user avatar
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How many iridium layers do we know, besides the K-Pg one (the dinosaur killer "smoking gun")?

The hypothesis of a large asteroid impact playing a role in dinosaurs extinction was strengthened by the discovery of a global iridium anomaly in the geologic record, at the Cretaceous–Paleogene (K-Pg)...
ksousa's user avatar
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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 ...
usernumber's user avatar
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Can I refill my saltshaker on Mars? [closed]

I guess we will need to take our lunch to Mars for some time before we are able to produce food there! But do we need to take a saltshaker too? Can we extract editable salt from the crust of Mars, ...
Handsome Nerd's user avatar
11 votes
1 answer
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Is there convection in Mars' mantle?

Mars is differentiated, with a core, a mantle and a crust. There are no (longer any) plate tectonics on Mars. Does this mean there is no convection in the mantle? Could there be convection in the ...
usernumber's user avatar
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2 votes
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Caves traced in nine planets of solar system

Are there chances of caves being found or traced on other planets of the solar system? What's the solution? Manufacturing special telescopes for viewing or observing caves on other planets? or ...
Prashant Akerkar's user avatar
11 votes
2 answers
600 views

When was the last volcanic eruption on Mars?

There are several volcanoes on Mars, including Olympus Mons, the largest volcano in the solar system, the volcanoes on the Tharsis bulge,... But they are all thought to be inactive now. When did the ...
usernumber's user avatar
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Why did the edge of Olympus Mons collapse?

On Earth, the maximum height for a mountain is ~10 km. Beyond that, the mountain will start to spread or collapse. On the surface of Mars, the gravity is not as strong, so the maximum height for a ...
usernumber's user avatar
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6 votes
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Are the Venusian "continents" likely to have existed before the global resurfacing event?

A topographic map of the surface of Venus shows the large highland areas Ishtar Terra, Aphrodite Terra and Lada Terra that have occasionally been described as "continents", plus various ...
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7 votes
1 answer
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How many quakes have been detected by InSight?

Insight has been on Mars with its seismometer for almost two years now. Has it detected any mars-quakes yet? How often do these quakes seem to occur? Is there a website where the current number of ...
usernumber's user avatar
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9 votes
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How did the Archimedes crater fill with lava?

This is the Archimedes crater, on the moon, near the Apollo 15 landing site. It is located in Mare Imbrium, a plain filled with lava. The strange thing is that the interior of the crater looks flat, ...
tutizeri's user avatar
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How old are the Martian blueberries?

The martian blueberries (only blue in false color) found by the Opportunity rover in Meridium Planis are formed by slow evaporation in mineral-rich liquid water. They obviously formed early in the ...
usernumber's user avatar
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2 votes
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Has the computed change of the axial tilt ever been measured?

Earth, the 3rd planet from the Sun, sometimes faces earthquakes and seaquakes that are so strong that they reportedly change the axial tilt and/or the rotation velocity. These changes are merely ...
Ioannes's user avatar
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Is there evidence for galactic "seasons"?

The Solar Year has huge effects on our climate, and the signs of passing seasons are physically evident on Earth. I recently learned about the Galactic Year. To my understanding, our sun orbits the ...
Tim's user avatar
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How scientists estimated the number of near-Earth supernovae over the last 11 million years?

According to this article on wikipedia, An estimated 20 supernova explosions have happened within 300 pc of the Earth over ...
user avatar
10 votes
1 answer
330 views

How strong are the strongest Ioquakes?

Jupiter's moon Io is the most geologically active celestial body in our system. It has the strongest volcanoes and quakes. Of course in practice these quakes wouldn't be as dangerous as on Earth for ...
user30007's user avatar
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14 votes
3 answers
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Are there any planets or moons denser than Earth?

Earth has the highest density out of all planets, planetoids and moons of our planetary system, and also has a higher density than the Sun. Do we know any exoplanets or moons denser than Earth?
user30007's user avatar
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Should only spherical satellites be considered 'moons'? [closed]

Since Titan and Ganymede fall into the same category as Deimos and Phobos or the components of planetary rings, the category of moons, it's like if all asteroids were considered planets. Tiny ...
user30007's user avatar
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Is there a general term used to identify the high flat features within Noctis Labyrinthus on Mars?

At the western end of Valles Marineris, where it mets Noctis Labyrinthus (highlighted section of image) there are a series of flat geological formations between the canyons. Is there a unique term ...
Bob516's user avatar
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2 votes
2 answers
361 views

Why are we so quick to proclaim the geological inhospitability of other planets based on extremely minimal information?

Now, I'm not questioning claims that any planet in the Solar System is atmospherically or externally inhospitable, but claims made that other planets have geology that is extremely hostile to ...
Grant Hartlage's user avatar
4 votes
1 answer
157 views

How to calculate the thickness of the ice crust on a frozen ocean planet/moon?

How do I calculate the thickness of the upper ice layer on cold ocean worlds like Europa, Enceladus, Ganymede, ...? I'm asking this for a programm I'm currently writing. Given/Known is: mass, radius, ...
TheDyingOfLight's user avatar
3 votes
1 answer
787 views

Could Mars have oil?

What events could have to happen to Mars (which is thought to once look like Earth) that may have depleted the atmosphere and erase all proof of life ever existing at least on the surface? I know an ...
Muze's user avatar
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1 vote
1 answer
167 views

Could an Earth-sized planet be cold?

This question poses the question of why the Earth is still hot after 4.5 billion years, and the primary reasons were: (1) heat from when the planet formed and accreted, which has not yet been ...
Daniel B's user avatar
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1 answer
821 views

Why is the Moon smooth near the equator and bumpy near the poles?

It looks as if it was polished by applying emery to its spinning equator. My initial guess was that it was simply an illusion caused by light direction, but the terrain map shows the same phenomena. ...
lolmaus - Andrey Mikhaylov's user avatar
3 votes
1 answer
467 views

Io: Why so much sulfur?

Io is the only body in the Solar System whose crust is dominated by sulfur and its compounds. Carbon and nitrogen are also very common in the universe but we don't see them or their compounds in Io's ...
MackTuesday's user avatar
4 votes
2 answers
867 views

Appearance of sun at geologic past

After origin of Earth ( 4.54 billion years ago ) to today; what are the changes through-which the sun undergone with time? , ( if seen from Earth. ) I'm doing some palaeobiology-landscape rendering; ...
Always Confused's user avatar
9 votes
1 answer
497 views

How much mass do the volcanoes of Io erupt past escape velocity?

While trying to do some calculations to answer this quesion, I got stuck missing a crucial piece of data: I have no clue how much mass the volcanoes of Io manage to throw out of the gravity well of ...
SE - stop firing the good guys's user avatar
5 votes
1 answer
434 views

If an earthquake happens on Mars, is it still an earthquake?

Or are seismic phenomenon named differently when they happen on other celestial bodies? If so, what are they called?
Etheryte's user avatar
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2 votes
1 answer
240 views

How massive must a rocky body be to liquify adequately to eliminate internal mass concentrations that could disrupt natural satellite orbits?

Maybe a slightly weird question, and maybe more appropriate for some future geophysics SE, but I feel like this is what questions like Do moons have moons? are really driving at, and it just almost ...
SudoSedWinifred's user avatar
9 votes
2 answers
8k views

What is the temperature 55 km beneath the surface of Mars?

What is the temperature 55 km (34.18 miles) beneath the surface of Mars? The reason I ask is that I want to know if it might be habitable for a possible future colony if they could dig that deep (...
Jonathan's user avatar
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1 vote
1 answer
3k views

What does the surface of Mercury look like?

What does the surface of Mercury look like? What color is it (I have seen some images portraying it grey and some a light brownish color), and would the surface be dusty like the Moon, smooth, or ...
Jonathan's user avatar
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6 votes
3 answers
385 views

Is extraterrestrial mining more difficult or impractical for bodies without plate tectonics?

This article talks about the possibility of mining Uranium on the moon. Since the Moon lacks the geological forces that have created veins of concentrated minerals on Earth, would extraterrestrial ...
12345678910111213's user avatar
4 votes
1 answer
405 views

Determining North-South Line Via Watch Method: Theory & Reason

I recently read that if you're in the northern hemisphere and have an analog watch, then you can point the hour hand at the sun and know that a south line lies between (bisection) the hour hand and ...
user8110's user avatar
2 votes
1 answer
412 views

How significant is a planet's density to the formation of life?

I'm doing some writing set on a fictional earthlike planet that for reasons needs to be substantially larger than Earth but can't have substantially higher gravity. I've been able to compromise with a ...
BB ON's user avatar
  • 129
4 votes
1 answer
178 views

How are boulders formed on asteroids?

For example: Are they soft landed meteorites? Or do they form from melted material during a violent impact? Or are they the result of some kind of erosion process?
LocalFluff's user avatar
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0 votes
2 answers
338 views

Do we have knowledge of the geology of the moon?

With reference to the Ebb and Flow lunar satellites, was there any data about its geology? Is there a central core, or is it homogenous?
Colin Shorey's user avatar
3 votes
1 answer
176 views

Long term effect on rocks of high pressure and temperature?

The mean surface temperature of Venus is about 460 C and the pressure is about 92 atmospheres. Assuming this situation (or similar) has prevailed for millions of years what changes (if any) would ...
gjh's user avatar
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1 vote
2 answers
249 views

Why do rocks on other solar system bodies that have an atmosphere seem to be flat?

Images taken by landers on Titan and Venus and Mars show landscapes where rocks, to me at least, are surprisingly flat. Being used to walking around in forests with roundish meter sized boulders, I'd ...
LocalFluff's user avatar
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2 votes
1 answer
473 views

What are these faint streaks on the moon?

I was poking around this Gigapan image of the moon's north polar region, when I noticed this area: What is the source of these light streaks? For position reference, here's a zoomed-out shot (I ...
sinelaw's user avatar
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