# Tag Info

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Berman and Hartman (2002) dated some lava flows of the Athabasca–Marte Valles system at < 20 Ma. Later, Vaucher et al. (2009) dated lava flows of the same region, finding ages even younger in some cases (around 2.5 Ma). In both studies the age estimates are derived from surface morphology (crater counts). In Volcanoes: Global Perspectives, Lockwood & ...

7

Would an impact event leave visible traces like impact basins, or could the entire surface melt and reform as it is today, as I suppose Earth did when the Moon formed? Could Venus have been a very different planet up until 0.3 billion years ago? How could one find out, what kind of investigation would be needed? Certainly giant impacts were fairly ...

6

No, it is not just a matter of migration. You need to take into account two facts. One is that (as experience shows) Io's own gravity is enough to avoid it breaking by tidal forces. It has been like that through all its history: Io could not have been formed if it started aggregating today, but it was formed at the same time Europa and Ganymede did: they ...

5

A long time ago. The major mare forming eruptions occurred more than 3.5 billion years ago, but a paper Ages and stratigraphy of mare basalts finds that some volcanic basalts are as young as 1.2 billion years. However, it seems that impacts have been the only active geological process for a billion years, giving rise to the observation that just as complex ...

5

It depends on the definition of Earth-like planet. In terms of size, density and gravity Venus is very Earth-like, but in terms of atmospheric and surface conditions and its axis of rotation, and period of rotation Venus in not Earth-like. I will assume you mean a terrestrial or rocky planet similar in size to Earth. Earth's crust has two subdivision: ...

4

Since this has gone unanswered, I'm going to give it a shot. Probably the answer is no. We know that on some moons, volcanic eruptions do send material into space. Enceladus for example, feeds Saturn's E-ring. It regularly shoots about 200 KG per second into space. The other highly volcanic moon in our solar system is Io which shoots material high ...

4

The velocity required to escape the gravitational attraction of a massive body is given by the following equation: $$v_{\mathrm{escape}} = \sqrt{\frac{2GM}{R}}$$ where $G$ is the gravitational constant ($G = 6.67 \times 10^{-11} \; \mathrm{Nm^{2} {kg}^{-2}}$), $M$ is the mass of the body from which you are escaping, and $R$ is its radius. Inputting the ...

4

Exoplanets are too far away to send satellites or to image them directly. So there is no way to go there and say: there it is a volcano. My guess is that we have to guess from what we know working in the solar system. And we might just get a statistical probability that the planet is active. I would say that there are two cases: If the planet is rocky and ...

3

My impression is that for answering your question, one would actually have to run simulations, ideally so-called global circulation models (GCM). If this is for a research project, the MIT GCM would be a good candidate to set up for the atmosphere of Io. Of course, there are research groups working on that issue, e.g. the team of Prof. Goldstein at the ...

3

Ishtar Terra belongs to the tessera type of terrain, "one of the most tectonically deformed types of terrain on Venus", representing ~7.3 % of Venus' surface (Ivanov & Head 2011, Global geological map of Venus). Tessera are "dated" (relatively, from stratigraphic relationships) from the Fortunian, the oldest period: The most ...

3

Reposting my own answer from Space Exploration on nearly identical question: The color dichotomy of Iapetus is due to the darker half, the Cassini Regio, being a result of the moon's accumulation of the dust in the Saturn's largest, yet extremely tenuous, diffuse dust ring called the Phoebe ring depositing onto the moon's leading hemisphere, while the ...

2

The short answer to your question is, "no," and that's for a couple reasons. There are a lot of different styles of volcanism, but they can be broadly classified as "pyroclastic" and "effusive." Pyroclastic is your classic volcanic eruption that looks like an explosion out the top. Effusive is more like a pot on the stove that ...

2

Source: JPL Article "The gravity anomalies along the border structures are interpreted as ancient, solidified, lava-flooded rifts that are now buried beneath the surface of the dark volcanic plains, or maria, on the near side of the moon." Because of the lava under Oceanus Procellarum, it's heavier/massive so it has a stronger gravitational pull than the ...

2

A younger lunar thermal history implies that the Moon was still undergoing a contraction and cooling process, which was initiated when it began accreting material together. Evidence has shown that the moon has no tectonic activity, so all geologic features are volcanic. The mare are a more recent example of this activity, and have been shown to have fairly ...

2

I would bet against lightning due to the very thin SO2 atmosphere; under normal conditions the pressure is 0.3 to 3 nbar, with plumes reaching 5 to 40 nbar. That does not sound like it could convey lightening. But given that the environment also has a lot of ionization there might also be all sorts of plasma and vacuum breakdown discharges. In short, I ...

2

What about the possibility that Venus (and its former moon) went through a much more rapid evolution then occurs normally? Typically a planet-moon system will undergo the following sequence of events: A large object hits the planet and a moon is formed. The planet rapidly tidally locks its moon The moon gradually slows down the rotation of the planet until ...

2

Depends on how Earth-like you want it to be. On Earth, most parts of the crust do not support volcanoes. But because we have active plate tectonics, there will always be places where plates slide beneath each other (subduction zones) or where they slide apart. Volcanoes are unavoidable in these locations, I think. A planet without plate tectonics could be ...

1

Braden et al. 2014 indicates that volcanism might have occurred on the Moon up to 100 million years ago. Most traces of volcanism such as the lunar mare are more than 3 billion years old. However, there are small patches that could have been caused by volcanism and that are ~100 million years old.

1

Per this article, the most recent volcanic activity on Mars might be less than 1 million (Earth) years old. Pyroclastic deposits in Elysium Planitia were dated thanks to impact craters and were found to be very young.

1

Is Io's orbit or rotation affected by its volcanism? The rotations of comets and asteroids are affected by outgassing volatilities. Io is very volcanically active. Does this give Io a varying orbit and a slow rotation? Jupiter's moon Io has a lot of volcanoes. A similar answer to your question is provided at Quora's question: "Could the eruptions of ...

1

There was once a very active argument over vulcanism on the Moon - with the distinguished amateur astronomers Patrick Moore and V. A. Firsoff the two leading advocates of vulcanism as having had a decisive impact on the Moon. The Apollo programme essentially settled this argument as far as craters were concerned - no serious figure seems to doubt these are ...

1

The grey areas are known as "maria" (singular:"mare") and they were formed from flood basalts. These are a type of volcano and they have formed on earth too, examples include the lake eruption on Iceland, and the Deccan traps, that played a role in the mass extinction 65 million years ago. On the moon, the flood basalt is old. About 3-4 billion years old, ...

1

I think the other answer is correct on migration, but there's a flaw in the way this question is asked, which should be addressed. It's also worth looking at the formation of Jupiter as well. One of the rules of planet formation is that angular momentum remains largely constant. Granted, some angular momentum gets transferred into heat, and some gets ...

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