Questions tagged [planetary-science]

The multi-disciplinary study of the geomorphology, geology, chemistry, meteorology, oceanography, hydrology, astronomy and astrophysics of the planets and other objects within the solar system.

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3
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2answers
521 views

Was there once a glacier over Starcke national park in Queensland Australia?

I was randomly exploring Google Earth when I came across some sort of rock formation in northern Australia. The location of the rock formation with respect to Australia is shown below. It is in or ...
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2answers
828 views

How long it takes to cool a planet?

Suppose a planet like Earth or Venus is totally isolated from sunlight. How quick would it cool down? On Earth it seems to me that the air temperature drops significantly even during a night. Does it ...
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Terrestrial Day vs. Venusian Day: Why the Huge Time Difference?

The diameters of Venus (7,520.8 miles) and Earth (7,917.5 miles) are comparable, but the disparity of the length of the day for each planet - as expressed in terrestrial hours - is enormous; a day on ...
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1answer
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What time and date is the sun directly overhead a given place on Earth?

In different regions, the sun is directly overhead at different times of the year. When do these event happen?
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2answers
201 views

What is the CI chondrite concentration of REEs/rare metals, in ppm/grams per ton?

I am researching the abundances of rare earth elements and rare metals in meteorite samples, because I want to investigate the notion that asteroids represent abundant stocks of rare resources. The ...
4
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1answer
117 views

doubt about the 'white spaces' in the maps from satellite

I have a doubt about the 'white spaces' in the maps from satellite. For example, for the atlantic areas I have plotted AOD and appear many areas where sistematically do not have any data (white spaces)...
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1answer
158 views

Melting basalt on the lunar surface - what would the resulting material be like?

The idea is to melt the fine-grain portion of basalt regolith using a large Fresnel lens, and let it cool to a solid. The lens would track along a tamped bed of material leaving a molten puddle ...
3
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1answer
237 views

How does water still exist on the Earth?

Almost all the theories that explain the origin of Earth says, it was way hot back then. That means It was in a lava state in its early days. Then gradually cooled down to the current state. If ...
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365 views

What is a weather system?

I heard on Star Talk Radio that Jupiter has weather systems larger than Earth so I was just curious to know what the definition of a weather system is exactly.
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3answers
730 views

What natural phenomena increase stratospheric ozone?

Most of us know that the ozone layer gets depleted due to green house gasses and other factors. Which made me wonder, is there any natural phenomenon that causes an increase in ozone?
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3answers
291 views

What are the conditions for an ionosphere to form?

I already asked this on Astronomy SE but did not receive any answer so far: What are the prerequisites for an ionosphere to form? For example, can a planet without any atmosphere have an ionosphere? ...
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3answers
581 views

How bad is geo-engineering?

It is just curiosity that forced me to ask this question. At some point in time, if we can't control global $\sf{CO_2}$ emissions, temperature will increase until a tipping point and it will be a ...
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1answer
50 views

Stars twinkling [closed]

What is the science behind the vigorous glow of stars ? Since 2 days I was observing one of the stars in blue and red colour I just want to know what is the speciality of that star?
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1answer
295 views

What are the relative contributions of planets to the Milankovitch Cycles?

When reading about the Milankovitch cycles here, it says: If the Earth were the only planet orbiting our Sun, the eccentricity of its orbit would not perceptibly vary even over a period of a million ...
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2answers
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Is there a time difference between two points at the same longitude but at different latitudes?

Assume we have two cities A and B both at the same longitude (say $45^{0}$ E) but at different latitudes say $8^{0}$N and $90^{0}$ N. Can we get a time difference between these two cities. I raised ...
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1answer
205 views

What is the current status of geophysical global cooling theory?

Plate tectonics effectively rubbished the theory of geophysical global cooling as a means of explaining many surface features on the Earth. However, this wiki says that the same process is responsible ...
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1answer
262 views

Source of sub-surface ringwoodite water

I was reading about the discovery of vast amounts of water locked up in ringwoodite (see here). The authors of the study seem to suggest that previous ideas, involving water deposits being delivered ...
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1answer
378 views

How will axial precession affect the weather in the northern hemisphere (UK latitudes)?

Unless there's a twin star to our sun in which case axial precession might be an illusion the Earth's wobble won't effect the total amount of energy received from the sun as is expected from increased ...
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1answer
95 views

Are oceans a major factor in creating high winds on a planet?

This question only pertains to oceans of water and how much they account for the process of creating high winds on a planet with any type of atmosphere.
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1answer
183 views

What would a planet's sky look like with different chemical compositions, such as low nitrogen, high methane etc?

What are the processes, chemicals and particles involved in creating colour in a planet's sky? Could you give some examples of sky colour processes different from what happens on Earth?
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what is the role of absence of land in south atlantic ocean cyclone formation [duplicate]

sir do absence of land plays role in formation of cyclone in south Atlantic ocean and east pacific ocean
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2answers
178 views

Mechanism for Pluto's young surface

According to recent reports (e.g. in Nature), Pluto is geologically active. It has some mechanism by which it has "recycled" its surface. I originally thought we had a similar case to Jupiter's moon ...
10
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1answer
107 views

Does the Sun's oscillation affect Earth's climate?

Today, discourse on climate change seemingly tends to focus on earthly elements such as pollution and human activity. While I am certainly not well-read on climate change research, after inspiration ...
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1answer
2k views

What color(s) would Earth be without water or life?

Many of the celestial bodies in our solar system have well-established color schemes, at least in the minds of the public. Mars is pale-red and black, Venus (beneath the clouds) is generally shown in ...
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2answers
206 views

Why are impact craters radially symmetric?

Okay, so I believe that most of the impact/collisions happen at oblique angles to the planet's radial direction. (I am not very sure about this, but since it is not a freefall, we can assume that the ...
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297 views

Impact craters vs volcanic explosions on Mars

A maar is a shallow volcanic crater with steep sides that is surrounded by tephra deposits. The tephra deposits are thickest near the crater and decrease with distance from the crater. Source: http://...
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1answer
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Mars maar craters explosive style formation gravitational effect

"Maars usually form when magma rises within a fissure and interacts with groundwater. If groundwater ceases to interact with magma at times during the eruption, continued magma ascent to the surface ...
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1answer
690 views

What would happen if we removed Earth's moon?

This question is an object of fascination of mine. There are a few different angles to take to it. My favorite is blasting the moon out of existence while its moving away from Earth. What would ...
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1answer
369 views

Did Jupiter really make Earth (in)habitable?

A new study by Batygyin and Laughlin suggest that a Jupiter migration toward the inner region of the Solar System during the early stages of system formation cleared the habitable region (Goldilocks ...
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1answer
158 views

How would weather change on a tidally-locked terrestrial planet?

On Earth, weather is very much affected by the Earth's rotation around its axis and around the Sun. Even locations that are almost on the equator do have strong annual variations in precipitation and ...
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6answers
2k views

Would life on Earth survive without the Sun?

Would life on Earth survive if Sun wasn't there? My teacher told me that there are chances that it would but there would be a lack of gases and chemicals and photosynthesis that occurs with light at ...
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2answers
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How does the Sun heat the Earth?

The core of the sun has a temperature of 15,000,000 °C. The surface of the sun has temperature around 5,000 °C. The sun is around 93 million miles (150 million km) away from earth. My Question: With ...
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1answer
344 views

What is this strange feature on Mars in Valles Marineris

While I was browsing Mars on Google Earth, I stumbled upon an interesting feature on one of the slopes of Valles Marineris. The feature seems unique in the sense that I couldn't find any similar ...
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1answer
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Differences between hydrothermal vents on Earth and Europa

Hydrothermal vents are common in areas subject to volcanic activity at the bottom of Earth's oceans. Meanwhile, hydrothermal vents are believed to exist on Jupiter's moon Europa and maybe in other ...
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3answers
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What are the criteria that make a planet (in)habitable?

Recently, I realized a lot of factors must contribute toward making a planet habitable, other than just the ones that come to mind like having oxygen, the right temperature, and so on. What makes a ...
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3answers
4k views

Do other terrestrial planets have “earthquakes”?

I know some planets have storms akin to what we have on Earth although obviously varying in nature. I was wondering if other planets have earthquakes? Since this comes down to plate tectonics (right?...
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1answer
475 views

Will dust storms be more frequent in the future?

I noticed that in some science fiction movies set in the future on Earth, like Wall-E and Interstellar, dust storms are very prominent. Are there any scientific hypotheses suggesting that dust storms ...
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1answer
304 views

What sort of instruments do planetary geologists use to predict that there are oceans on the moons Titan and Europa?

NASA Planetary Scientists released a video that says they have confirmed that there is an underground ocean in Europa and that Titan has liquid oceans made of hydrocarbons. I myself am an aspiring ...
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5answers
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How do we know the asteroids formed at the same time as earth?

In continuation of the question Why is Earth's age given by dating meteorites rather than its own rocks?, what evidence do we have that the asteroids indeed formed at the same time as earth? Is there ...
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1answer
248 views

'Late Veneer' on other planets

Is there any evidence of external material source events, like the 'Late Veneer' on other planets? Or is this theory specific just for Earth? Note, that this question may be related to How and why ...
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3answers
405 views

How do archaeologists address time dilation when analyzing carbon dating results?

It is a proven fact that the gravitational force exerted upon an object directly affects that objects experience of time; the greater the gravity, the slower time passes, and visa versa. While the ...
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1answer
357 views

How much silicon is in the Earth's core, and how did it get there?

With some informal conversation with a peer of mine, he had suggested that there is evidence (which he couldn't find,but had remembered reading) that there was Silicon in the Earth's core. I referred ...
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2answers
414 views

To what accuracy and precision do we know the volume of the Earth?

Satellites such as GOCE and GRACE measure the geoid with unprecedented accuracy. Altimeters can determine local surface elevation with millimetre-precision. This makes me wonder: to what precision ...
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1answer
103 views

What properties must a rocky body possess in order to exhibit the magnetic dynamo?

The magnetic field of the Earth is produced by the magnetic dynamo. What conditions must a rocky body possess in order to exhibit the dynamo? Clearly, the planet's interior must not be too cold. ...
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2answers
2k views

What sort of climate zones would be present if Earth was tilted like Uranus?

The three main climate zones on Earth are tropics, temperate and polar. Due to Earth's axial tilt, the three zones experience different seasonal patterns: The tropics experience 2 or 4 wet/dry ...
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1answer
1k views

Can Venus be considered to be tectonically active?

Venus is noted for its absence of spreading ridges, transform faults, and subduction zones, which are characteristic of plate tectonics on Earth. But given that it exhibits rift zones, mountain belts ...
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2answers
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Geomorphology of Mountains With Wind only Erosion

I am curious what mountains would look like if erosion occurred almost entirely by wind. Specifically, I am curious of how granite mountains would look on a "snowball" terrestrial-sized xenoplanet. ...
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1answer
513 views

Is there geological evidence that the moon once collided with the Earth?

I've seen models in astronomy that show how the Earth-Moon system must have come together after a collision. However, I have not heard whether there is any actual physical evidence on Earth that ...
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1answer
181 views

Why does helium-3 stay in the moon and not escape from it?

So the moon is full of helium-3. Since it's a gas in the moon's vacuum... Why doesn't it escape?
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2answers
771 views

Why do some planets have lots of $\mathrm{N_2}$ and others none?

Earth, Titan and Venus all have large amounts of $\mathrm{N_2}$ in their atmospheres. (In the case of Venus it's a small proportion, but Venus' atmosphere is very thick, and the total mass of $\mathrm{...