Expanding Matter. And Space, to a lesser degree?

Same packing geometry, same ratio?

The moon's radius is just over 1/4 that of earth, so that part doesn't seem far off. The more non-intuitive bit for me was that the moon has only 1/81 of the mass of Earth, how could its gravity be so strong? Though a bit of math makes that puzzle go away.

 

Composition is clearly a factor. Earth has a very large hunk of iron as a core, I don't believe the moon's iron hunk is proportionately as large.

 

Moon mass ~1/80 Earth mass, but on the moon you get to stand a lot closer to its heaviness. One over r squared is in function here and in so many other places, hard to count them all.

Remember Avogadro but not his number? Earth mass is 10 moles of kilograms. Now you can forget both numbers at the same time. Efficiency

But in a qualitative sense, since everybody has a handle on what a kilogram feels like, and at least general idea that Earth is a heavy thing, it help with appreciating that a mole is an awfully large number of things.

Solar mass is about 300,000 moles of kilograms. Big eh?

 

My memory has it the other way. His number is well engraved in my memory, but Earth's mass is not. So this hint-link should help.

I'd read about the mountain ranges and atmospheres on neutron star a very long time ago. The centimeter or inch tall scales were quite impressive.

Somewhere along the line was also an item about spectroscopic observations of a thermonuclear chain reaction 'explosion' on the surface of a neutron star, as an accumulated layer of hydrogen (from in-falling gas from a companion star being cannibalized) ignited and burned. In this case, "burning" means fusing into whatever next stage happens on a neutron star, something beyond what happens in our hydrogen bombs. The emitted radiation was both showing absorption lines to help reveal the properties of the atmosphere it was passing through, and providing more verification of General Relativity from the red shift of climbing out of the gravity well.

It was mind-blowing that this continuing thermonuclear explosion was happening beneath an atmosphere no more than an inch thick.

 

Made mostly of iron56 and "lighter" elements?

 

Yeah, that’s about what happened the last time I tried ordering a double secret burrito-dog at Pink’s.

 

Only problem with Pink's is that you have to go to LA to get one.

Worse...you used to have to go to Doyers Stadium itself to get a Dodger Dog - although some Angelinos would insist that this is still the case.

Sadly....
Since I'm a non-virtue-signaling herbivore these day, I must enjoy my pork wieners vicariously.....

 

That detail wasn't part of the old item I read. The temperatures there are well above the iron's earthly boiling point, though I lack information about boiling points and vapor pressures under those conditions.

 

Oh, you’ve been to Pink’s too?

 

Once while at a catfish fry in TN. while visiting friends in Olive Branch Mississippi, I was given a home grown pepper to sample. Being ignorant of possible
foul play or trickery, I took a normal bite of the pepper only to find out it was one of those on the higher scale of the HOT spectrum. It didn't take more that a few seconds to realize my mistake. It did take almost an HOUR during which many oral burn remedies failed to reduce the sensation of layers after layer of dermis falling away, even while in the pool and continually filling with pool water and spitting on the grass.
A lot like NASA describes what happens to a White Dwarf Star.
White Dwarfs

https://imagine.gsfc.nasa.gov/science/objects/dwarfs2.html