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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In which Indian Institutions can I find Planetary Scientists or Planetary Geologists?

Which institutions in India provide labs and facilities for research in the field of Planetary Sciences/Planetary Geology?
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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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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 ...
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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 ...
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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,...
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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 ...
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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)...
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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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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, ...
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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 ...
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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 ...
11 votes
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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 ...
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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 ...
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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 ...
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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, ...
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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 ...
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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 ...
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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 ...
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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 ...
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10 votes
1 answer
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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 ...
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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?
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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 ...
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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 ...
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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 ...
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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, ...
3 votes
1 answer
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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 ...
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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 ...
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1 answer
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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. ...
3 votes
1 answer
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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 ...
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2 answers
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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; ...
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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 ...
5 votes
1 answer
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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?
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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 ...
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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 (...
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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 ...
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6 votes
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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 ...
4 votes
1 answer
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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 ...
2 votes
1 answer
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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 ...
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4 votes
1 answer
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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?
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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?
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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 ...
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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 ...
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2 votes
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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 ...
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Radioactive decay is the main source of the earth's interior heat: fact or theory? [closed]

It's believed the main reason that the interior of the Earth hasn't cooled down in 4 billion years is because of the ongoing decay of radioactive elements that keeps adding more heat than is lost to ...
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Why are most lunar maria on the visible side?

Is there any reason why the Earth side of the Moon has enormous plains and mountains, while the far side contains just few small ones inside largest craters?
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Would it be possible to calculate the expected frequency of impact craters of all sizes on Earth

Can the expected frequency of all sizes of impact craters on Earth be calculated based on the preservation of impact craters seen on the Moon? Taking into account the difference in gravity and ...
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Why is the Earth's center still hot after millions of years? [closed]

Why didn't the center of the earth cool after millions or billions of years? What keeps it hot?
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Why isn't Earth a perfect sphere? [closed]

In general, almost everyone describes Earth as an perfect sphere, but in reality it isn't a perfect sphere. Is there any specific reason why Earth is not perfect sphere ?
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