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22 votes

Could an icy/extremely-cold asteroid/comet ever strike and cool the Earth?

Could an icy/extremely-cold asteroid/comet ever strike and cool the Earth? No. The smallest possible velocity is about 11 km/s velocity, and that would require a near miracle. For that to happen, the ...
David Hammen's user avatar
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21 votes

Could an icy/extremely-cold asteroid/comet ever strike and cool the Earth?

I'm gonna sail against the wind and say "yes", indirectly. Although you don't need a cold asteroid, a "normal" one would suffice. When striking the Earth, asteroids eject a large ...
Jean-Marie Prival's user avatar
13 votes
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Water on Mars and Earth

If water on Earth came from meteorites, why doesn't Mars have substantial water? First off, that's a conjecture regarding the origin of the Earth's water rather than a known fact. A few times a year ...
David Hammen's user avatar
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13 votes

Could an icy/extremely-cold asteroid/comet ever strike and cool the Earth?

No, it's not possible to cool the Earth with an asteroid impact. The mass of any asteroid that could hit the Earth is far too small to be a heat sink. The asteroid that killed the dinosaurs had a ...
gerrit's user avatar
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12 votes
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Why don't iron meteorites on Mars rust or oxidize? Why are they shiny?

tl;dr: Compared to Earth, the atmosphere on Mars is very thin; in addition, it contains much less of oxygen and water (i.e., is very dry). It is much colder there. These conditions may slow down ...
Buttonwood's user avatar
12 votes

Could an icy/extremely-cold asteroid/comet ever strike and cool the Earth?

For your purpose (energy in the entire system) it doesn't matter if the asteroid lands gently or not because energy is conserved: If the asteroid slows through some kind of atmospheric braking, then ...
user3067860's user avatar
8 votes
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Could diamonds be formed from coal?

Craters actually can be identified by formation of high-pressure materials such as diamonds or stishovites and coesites (varieties of shocked quartz). A good example of this is the Popigai crater in ...
Gabija's user avatar
  • 549
6 votes
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Is it possible to estimate the size of a meteorite from its remains?

Meteors enter the atmosphere at speeds ranging from 11 km/sec, to 72 km/sec. Those speeds are so large that if a meteorite were to hit the surface at that speed, the energy released would be more then ...
Camilo Rada's user avatar
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6 votes

Is the "Kartenhoff" meteorite real?

The story told in the movie about the meteorite is fictional. Here is a quote: The Kartenhoff, the oldest in human possession. The very meteorite which made this crater. The Kartenhoff is a ...
Camilo Rada's user avatar
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5 votes
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Is there any new water formed on, or brought to, Earth?

Your explanation(s) sounds correct. Your first article says as much. There is a water cycle on earth that takes wet sediments deep into the mantle to be re heated and circulated back up as new ...
userLTK's user avatar
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5 votes
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Safest spots when an asteroid hits?

Being in a submarine in the ocean is not a good idea because if a large asteroid hits the ocean the shock wave created, and its energy, would be very large. If the submarine survives intact its ...
Fred's user avatar
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5 votes

Water on Mars and Earth

Mars did have a significant amount of water (and atmosphere) early in its history. According to NASA, there was enough to form an ocean covering about half its surface: https://www.nasa.gov/press/...
jamesqf's user avatar
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5 votes
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Importance of meteorite impact craters in geology?

Impact diamonds Yes, diamonds can form in meteorite impacts. For this several things need to happen: A meteorite of the correct size and velocity, The stuff it hits needs to contain carbon. If you ...
Gimelist's user avatar
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5 votes

Why are there craters on the moon?

I'd like to expand on jamesqf's answer. But first, lit side of the moon and the dark There are no "lit" and "dark" sides of the moon. It rotates, and whatever is dark now will be lit in two weeks ...
Gimelist's user avatar
  • 23.2k
5 votes

Could an icy/extremely-cold asteroid/comet ever strike and cool the Earth?

One asteroid or comet, no. Even it it was huge you might get a planetary extinction event like the meteorite that crashed into the Yucatan region resulting in the dinosaurs dying out. That would be ...
Fred's user avatar
  • 24.7k
4 votes

Why are there craters on the moon?

There are craters on the Earth, Arizona's Meteor Crater being perhaps the best-known example. The reason that there aren't a lot more (obvious) ones is that the Earth has lots of dynamic processes, ...
jamesqf's user avatar
  • 1,758
4 votes

Luis Alvarez's K-T Impactor Calculation

The volume of a sphere is $\small\sf{\frac4 3\pi R^3}$, where $\small\sf{R}$ is the radius. The volume of Earth with the 4 cm deep iridium rich layer is, $\small\sf{V_{Ei} = \frac 4 3\pi (6.378\...
Fred's user avatar
  • 24.7k
4 votes

Could an icy/extremely-cold asteroid/comet ever strike and cool the Earth?

Thermodynamically No Jean-Marie gives a good answer about aerosol effects. Others observe that impacts add energy to the planet. I would simply like to look at the energy budget. The sun dumps on ...
Lawnmower Man's user avatar
4 votes

Would a gold-containing meteor cause it to "rain" gold?

As it melted, it would be broken up into a spray or even a mist by the airstream. The droplets would quickly slow down to their terminal velocity and solidify, so you would get a fine gold dust ...
Mark Foskey's user avatar
4 votes
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What is the metal left behind by meteorites called?

Shocked quartz has been found at underground nuclear test sites and major meteor impact sites. It is formed when quartz is subject to intense pressure causing to deform internally along crystal planes....
Fred's user avatar
  • 24.7k
4 votes

What is the metal left behind by meteorites called?

Was it impactite? It is the name of rocks (not metal) that have been transformed by a meteorite impact. They contain evidence for high pressures (quartz transformed into coesite, its high pressure ...
Jean-Marie Prival's user avatar
4 votes

Identifying dense magnetic rock with tubular features

The items look like slag, the dumped wasted product of metal smelting. The high density suggests a high metal content. The magnetic properties suggests a significant iron content and the smooth curved ...
Fred's user avatar
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3 votes
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Haean, South Korea: is it of volcanic or meteor impact origin?

A Korean here. Haean Myeon in Gangwon-do has two theories of creation. One is Meteor impact and another is differential erosion. There were no meteor related evidence found at Haean so the erosion ...
Arandomstudent21's user avatar
3 votes
Accepted

Does the heat of reentry affect the reliability of radiometric dating of meteorites?

Current consensus says heat does not affect the rate of radioactive decay and if it does it is due to time dilation, the effect of whihc is very small. Thus the heating of meteorites as they enter ...
Fred's user avatar
  • 24.7k
3 votes

Would a gold-containing meteor cause it to "rain" gold?

Would a gold-containing meteor cause it to “rain” gold? No. First, it is a bit unclear what do you mean by "gold-containing meteor". All solar system bodies have gold, the question is how ...
Gimelist's user avatar
  • 23.2k
3 votes

What is the metal left behind by meteorites called?

The metallic components of meteorites are made of nickel-iron, usually taenite that has a nickel content between 20% and 65% and kamecite with between 5% and 10% nickel. There are other elements mixed ...
Ken Fabian's user avatar
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2 votes

Importance of meteorite impact craters in geology?

Nowadays impact craters are of little significance. Back in the Hadean era of early planetary crust formation, bolide impacts were the defining process of planetary evolution. As for diamonds, one ...
Gordon Stanger's user avatar
2 votes
Accepted

Iron-nickel phase in pallasite meteorites

First, a correction. A solid solution is between different compositions in the same phase. For example, olivine is a solid solution of forsterite (Mg2SiO4) and fayalite (Fe2SiO4). There are two common ...
Gimelist's user avatar
  • 23.2k
2 votes

Does a registry for fallen meteors exist?

The short answer is "yes" and the links are provided below. Fireball reports: https://www.amsmeteors.org/fireballs/fireball-report/ Classified meteorites: https://www.lpi.usra.edu/meteor/
Rokman's user avatar
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