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Scientists discover Kelvin-Helmholtz Instability on the surface of the Sun

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31–40 of 65 posts

Re: Scientists discover Kelvin-Helmholtz Instability on the surface of the Sun

#31

The Sun impresses me. So much energy to dish out, so little of that is taken by planet Earth yet it helped yield and maintain life. Now what will happen when that energy is taken away ...

Why would the sun’s energy be taken away?

It's the impending and inevitable heat death of the universe... several billions of years away...

Re: Scientists discover Kelvin-Helmholtz Instability on the surface of the Sun

#33

The Sun impresses me. So much energy to dish out, so little of that is taken by planet Earth yet it helped yield and maintain life. Now what will happen when that energy is taken away ...

We still have our core There may be rogue planets out there sustaining life far from any star..

There is. They had a civilization long ago, but now they're down to a small village and only have a radio that they use once every 1000 years.

I managed to talk to them a few years back on my ham. They asked me to send them energy, I told them we'd need to figure out fusion energy first and that we'd get back to them next millenium.

Re: Scientists discover Kelvin-Helmholtz Instability on the surface of the Sun

#34
post #31

Earlier quoted context omitted.

Why would the sun’s energy be taken away?

It's the impending and inevitable heat death of the universe... several billions of years away...

I think you're off by about 90 orders of magnitude for the actual heat death

Re: Scientists discover Kelvin-Helmholtz Instability on the surface of the Sun

#35
post #6

This kind of observation is a big deal for solar physics. It's been believed for decades that these small-scale (~100km and below) turbulent features are critical to understanding how energy dissipates in the Sun. And thus, how sunspots and flares form. The subject has been very qualitative but is yielding on both observational and simulation fronts. I worked adjacent to this area from the 1990s-2010s, and it had bee…

Silly question but how does a 4m aperture focused onto a smaller area not concentrate the heat and melt the instruments?

Re: Scientists discover Kelvin-Helmholtz Instability on the surface of the Sun

#36
post #6

This kind of observation is a big deal for solar physics. It's been believed for decades that these small-scale (~100km and below) turbulent features are critical to understanding how energy dissipates in the Sun. And thus, how sunspots and flares form. The subject has been very qualitative but is yielding on both observational and simulation fronts. I worked adjacent to this area from the 1990s-2010s, and it had bee…

Silly question but how does a 4m aperture focused onto a smaller area not concentrate the heat and melt the instruments?

It's highly filtered, you are only getting a small slice of all of the wavelengths. Only a tiny fraction of all that energy hits the photo collector. I believe the collector is also actively cooled, but I might be wrong there.

Re: Scientists discover Kelvin-Helmholtz Instability on the surface of the Sun

#37
post #24

Earlier quoted context omitted.

Obviously not based on DNA/RNA. I think it is pretty lacking in imagination to believe that DNA/RNA in liquid water is the only possible configuration of atoms that could make a self-replicating and evolving organism.

Imagination is great for writing science fiction but it doesn't change the laws of physics that make the sort of organization needed for life impossible. You write "configuration of atoms" but there's no such thing within stars.

There is a sort of island of complexity in the parameter space of physics where we exist in a thin film on the surface of a rock orbiting at such a distance of a star of a particular strength.

It is a bit presumptuous to dismiss out of hand that this is the only possible island of complexity in the universe and there are not other sets of parameters with similar entropy-fighting characteristics.

Re: Scientists discover Kelvin-Helmholtz Instability on the surface of the Sun

#38

Earlier quoted context omitted.

> The subject has been very qualitative What does this mean?

"Qualitative" means that the field had good conceptual theories, but didn't have sufficient observational and computational resolution to determine the detailed numerical values

Well put. And to round out the nomenclature for those that are curious, the corollary here is that it can now become much more quantitative.

Re: Scientists discover Kelvin-Helmholtz Instability on the surface of the Sun

#40
post #6

This kind of observation is a big deal for solar physics. It's been believed for decades that these small-scale (~100km and below) turbulent features are critical to understanding how energy dissipates in the Sun. And thus, how sunspots and flares form. The subject has been very qualitative but is yielding on both observational and simulation fronts. I worked adjacent to this area from the 1990s-2010s, and it had bee…

> The subject has been very qualitative What does this mean?

quality vs quantity

seeing something new vs observing same stuff many many times to do statistics

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