We should at least have referred to the corona instead of the surface.
When it comes to the opposite, the coldest temperature in the known universe has actually been man-made (also in lab settings).
Comment on I've noticed that people make the 'surface of the sun' temperature comparison a lot
cloudless@feddit.uk 10 months ago
By the way, in 2012, scientists on the LHC were able to create the highest man-made temperature, at an astounding 5 trillion K – the temperature of the universe moments after the big bang.
aeki@slrpnk.net 10 months ago
Scubus@sh.itjust.works 10 months ago
I only vaguely recall this, but I seem to remember reading that using lasers we can actually get things into the negative kelvins? Or maybe we get them so cold they become hot? TBH I can’t remember and it confused me when I read it, but I remember it being a reputable source
wahming@monyet.cc 10 months ago
That article needs an ELI5 section.
Solemn@lemmy.dbzer0.com 10 months ago
Try this one, I found it easier to at least think I understand what it’s talking about: quantum-munich.de/…/Negative-Absolute-Temperature…
Basic attempt at eli16: Temperatures are defined by entropy, rather than kinetic motion like we’re used to thinking. In certain constrained systems, it’s possible to create a situation where there is a maximum energy state, and saturating the particles in the system such that they’re all close to that state creates a situation where the entropy starts decreasing (the system is less disordered since all particles are at the same maximum energy). That state where the entropy is decreasing is where negative temperatures exist.
End attempt. Disclaimer, I’m probably wrong, having spent just a few minutes skimming these two articles and trying to summarize what I understood.
Rodeo@lemmy.ca 10 months ago
How do we know what the layers of the sun and earth are, and how hot they are? What methods were used to gain (or theorize) this information?
cogman@lemmy.world 10 months ago
The sun is based on physics and observing nebula and super novas. We know how much the sun weighs based on it’s gravitational pull. We know what it’s currently burning given the frequency of the light it emits. We know what generation it is based on the elements in the planets. And we know the contents of other stars by the light they emit when they explode and collapse.
We know the layers of the earth because we can bounce sounds off the earth’s core to see how deep it is. We know roughly what it’s made of because we know how much the earth weighs and that the earth has a magnetosphere (you only get that with certain metals).
The methods used are generations of built up knowledge in physics and astrophysics.
You can, of course, just google these questions and get better answers than my summation
Umbrias@beehaw.org 10 months ago
Loss and lots of science and math to model and simulate the sun in a variety of ways slowly weeding out the models that weren’t making experimentally validated predictions. I’m not sure how many astronomers are around, especially sun focused ones, on Lemmy to answer you more specifically about the history of sun science.
skillissuer@discuss.tchncs.de 10 months ago
5500C? i thought it’s not that much, chemistry can get you there
apparently not
thermite tops at some 2000C-something, and in any case can’t work above boiling point of aluminum (2470C)
only in few cases of adiabatic flame temperatures reach above 4000C, and all in oxygen. highest listed in wikipedia is oxygen/dicyanoacetylene at 4990C. maybe some wacky highly fluorinated oxidizer will allow for even higher temperatures. adiabatic detonation temperatures also top out at some 4500C even for the most energetic explosives
so really only practical way to get to 5500C is through use of electric arc
kbal@kbin.melroy.org 10 months ago
What if we pre-heat the room to 3000, then very quickly introduce the explosives and run away before detonation?
skillissuer@discuss.tchncs.de 10 months ago
if there’s no room left after measurement, did it really happen?
Klear@sh.itjust.works 10 months ago
5 trillion K is a lot more than 5500 C.
Noodle07@lemmy.world 10 months ago
He’s talking about the surface of the sun
Klear@sh.itjust.works 10 months ago
Oh, in the picture. I haven’t realised it’s a part of the parent comment, only read the text.
Makes way more sense then.
wahming@monyet.cc 10 months ago
You’re only off by about six zeros.
HeckGazer@programming.dev 10 months ago
Surely a laser would be way more practical
skillissuer@discuss.tchncs.de 10 months ago
depends on what do you want to heat up. hint: at 5500C you need to handle plasma anyway