Recent comments in /f/askscience

kyler000 t1_j2bw3sk wrote

Do you have more info on how volcanic carbon emissions affect foliage? It seems like there would still be plenty of carbon to go around and that volcanos just contribute more to the carbon cycle. Or is it part of the cycle? Like some carbon is sequestered due to tectonic activity and then released by volcanos?

1

majorpickle01 t1_j2bvhwy wrote

from the very limited reading I've seen into the subject the idea is it would be detectable in the CMB - something along the lines is it would affect the distributions of bands or something like that.

If you do some digging for papers on it there's are suggestions on how to test for it / physical consequences

1

Bad_DNA t1_j2bvgh8 wrote

The source of the energy? The Sun. On many days, it will be a noticeable thermonuclear ball in the sky emitting no small amount of energy. That energy comes in many frequencies, some of which are absorbed by chemical compounds in our atmosphere and upon the surface of our planet.

3

Josephdirte t1_j2btpn5 wrote

Sorry if I'm missing something in your comment, but it seems to imply that the earth's core started out incredibly hot and has been cooling ever since without any additional heat generation, rather, relying on insulation to retain residual heat. It's important to note that ongoing radioactive decay within the earth's interior, together with the insulation you discussed, continues to keep earth's core hot and capable of sustaining plate tectonics.

3

Dd_8630 t1_j2bsp18 wrote

>Some physicists are questioning if General Relativity is totally accurate.

No physicist has ever thought that GR is totally accurate, not even Einstein. We've known from the very beginning that GR and QM are incomplete.

>The simulation has limits so the extreme edges "break" the rules.

What rules does it break? The universe is under no obligation to obey human intuition.

>It is possible the universe is the same way...

That's absolutely nothing to suggest that it is. We humans evolved to have an intuitive understanding of the world we interact with; therefore, we should expect physics to diverge from our evolved intuition when we go beyond humans scales - namely, the very small, very large, very vast, very hot, very rarefied, etc. Go beyond STP and scales of metres and seconds, and we should expect to hit counterintuitive results.

It would be more indicative of a contrived simulation if we didn't encounter edge weirdness.

3

OlympusMons94 t1_j2bne1r wrote

No. An induced magnetosphere (like Venus, Mars, Europa, Titan, comets, etc. have) doesn't require or have anything to with the core. It just requires the presence of some kind of atmosphere, in which the magnetic field is to be induced.

An intrinsic magnetosphere (like the Sun, Ganymede, Earth, and the other five planets have) is by definition generated in the interior of a planet, and for rocky/terrestrial planets lile Earth and Mercury this would tend to be in the metallic core (as opposed to the rocky mantle). But gas giants and ice giants generate their intrinsic magnetic fields above their core. For example, Jupiter's and Saturn's magnetic fields are generated in their liquid metallic hydrogen mantles.

An "active core" isn't really a scientific term, and can have different meanings in popular discourse. The usual, better meaning is that there is an active dynamo in the core, generating an intrinsic planetary magnetic field. But the absence of an intrinsic magnetic field and the core therefore not being "active" in this way does not imply the core is solid (let alone not rotating; all cores rotate along with the rest of the planet). There needs to be additional forcing to generate a dynamo. (For example in the case of Earth's core, the freezing out of the inner core causes the outer core to convect. Planetary rotation twists this vertical convective motion into spirals and this combined motion drives the dynamo.)

Often, "active core" is instead or additionally taken to indicate or be synonymous with active volcanism or tectonics. But these are driven by processes in the mantle and crust, and not directly related to the core, let alone the magnetic field. So this idea of an "active core" is "not even wrong".

1