Saturday, March 20th, 2021

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Today is a day where I have a shopping list for the hardware store.

Mr Rogers would have been 93 today

Mr. Rogers was born today in 1928. As amazing as his show is, I always think of his speech on Capitol Hill beseeching Congress to not cut the funding that drives PBS.

I've been on a deep dive into craftsman and maker channels on YouTube. I came across this wonderful video of an 80 year old man working in his forge and making a knife from start to finish.

3/20/2021 12:16 pm | | Tags: craftsmanship, maker, blacksmithing

Is the surface of the sun solid

/u/Solestian asked:

This might seem like a stupid question, perhaps it is. But, let's say that hypothetically, we create a suit that allows us to 'stand' on the sun. Would you even be able to? Would it seem like a solid surface? Would it be more like quicksand, drowning you? Would you pass through the sun, until you are at the center? Is there a point where you would encounter something hard that you as a person would consider ground, whatever material it may be?

/u/VeryLittle gave this excellent answer:

Before anyone goes mocking this question, it's actually very clever. Let me explain.

The sun is fluid, all the way through, even if that fluid is very different than any you might be used to on earth. It's a plasma, meaning that the electrons are separated from the nuclei (though the level of ionization varies with temperature and depth). This traps light, specifically photons, which bounce back and forth between charged particles.

The deeper you go, the denser this plasma gets, as it gets compressed by all the weight on top of it. The outer most layers of the sun that you see, 'the photosphere', is just the part where this plasma has such a low density that photons can escape from it. But it's actually a layer about 300 km thick, because the average distance a photon can travel here before bumping into a charged particle is a few 100 km. This means they escape, shining off into the solar system. This does a good job of giving the sun an apparent 'surface,' but it is by no means solid, and the sun extends well above the photosphere.

So if you were invincible, impervious to the incredible heat of the sun, what would happen if you tried to stand here? Well, you'd fall like a rock. The density of plasma in the photosphere is far less than the density of earth's atmosphere- you'd fall as if there's almost no drag. It would be like freefall- very, very hot freefall.

So would you ever stop falling? Yes! Why? Bouyancy, from your relative density. Denser things sink, like rocks in water, but less dense things float, like helium balloons in air. And remember, the sun gets denser as you go down. The core is a hundred times denser than you, so if I tried to put you there, you'd float up. Wherever you start, you'd eventually stop when you reach the part of the sun that is just as dense as you, about 1 g/cm3. Coincidentally, that's halfway down through the sun.

Needless to say, I don't know how you're planning to get yourself out of this mess, but I hope you brought some spare oxygen tanks.

3/20/2021 4:36 pm | | Tags: science, space
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