Is the Sun Solid?

Factual Questions
1

This seems stupid but I’ve never heard an answer to this.

Ignoring all the inconvenient details of being burned alive or being squished by gravity what would it be like to toucj the sun?

I would guess the outer layers would seem like a gas (I know the sun is plasma which is sometimes described as a 4[sup]th[/sup] state of matter after solid, liquid and gas).

Still, if you peeled off a few outer layers of sun and then ran in to it would it be like hitting a brick (or harder) wall or would it separate more like a think goo (good technical term huh?)?

I’ve heard a teaspoon of Neutron Star material would weigh as much as Mt. Everest on earth. Would that teaspoon of goo be rock hard or could you stir it (assuming you were strong enough)?

2

OK, where do I begin.

Newton. His law of universal gravitation states that all matter attracts all matter (hence Rick Ocasek and Paulina Poriskova [ how else could you explain it]).

There are lots of atoms in the universe. They have mass, they attract each other. Over time, they can get real close and form a dense cloud - denser than the clouds in the sky. As the atoms get closer together, they bump and the kinetic energy they have from moving is transformed to thermal (heat) energy. Eventually, this can increase until the process of fusion begins (atomic nuclei combining). The cool thing is that fusion gives off GOBS of energy and thereby sustains itself (the energy given off by one set of fusing nuclei start the next pair a-fusing, with energy left over). This left over energy is given off in the full spectrum (from gamma to radio wavelengths).

Your question is based on the understanding that as these particles get closer together the overall density increases until the van der Waals forces take over and some sort of structure begins to take shape (liquid or solid). Fact is, however, that the energy released is so great that the atoms can’t get close enough long enough for the vfW forces to take over. Imagine trying to compress steam back to water but the steam is so hot that no matter how much pressure you apply, the steam stays “boiling”. (note to other readers: I’m trying to keep this elementary; please don’t bust my chops about steam vs. vapor)

This process of energy release and attraction towards the center keeps the atoms that make up the sun (mostly Hydrogen) stirred up. As the fusion continues, the hydrogen fuse to helium and lithium, etc. This takes a long time.

Eventually, the star will run out of fuel (hydrogen). When this happens, the pulling in force (mass attraction - gravity) is greater than the pushing out force (from energy release) and the star collapses. Depending on the total mass of the star, different things can happen.

Here’s where my knowledge gets a bit fuzzy. Stars basically come in three sizes.

  1. wee
  2. not so wee
  3. friggin’ huge

Wee stars just kind of burn out. These, I believe, collapse into themselves and become dwarfs. Real dense, real boring.

Now so wee stars collapse quickly. They are small, incredibly dense, and not as boring. because they collapse quickly, not all of the energy is released. These resulting stars emit radiation in different forms and are called neutron stars, pulsars or whatever, depending on the radiation emmition.

The friggin’ huge stars collapse so quickly that they form a piece of mass that is phenominal, but the density is so huge that the gravity is tremendous. This star can’t hold it’s own weight, so to speak, and keeps drawing itself in until it is “infinitely” small. The gravity is now so darn strong that EVERYTHING near by gets sucked in! This is so darn strong that light (photons) far away get bent around it (direction of travel changes) and photons closer actually get sucked in!!! This is the venerable Black Hole.

Now to your question. Stars regardless of size, are the “burning” things. When they are no longer stars (burned out) they are neutron stars, pulsars, etc.

Our star is pretty small and light (non-massive) in the way of stars. If you could fly your space ship into it, you would go right through it. You wouldn’t hit any wall or solid core.

Brightly,
Spritle

3

Well, lemme tell ya:

-They Might Be Giants, “Why Does The Sun Shine?”

4

hmm…I thought I once read that the sun’s density increases with depth (makes sense) and if you could survive the heat et al., then you would reach a density that is on par with what we associate with solids. But, given the temperatures involved, I assume this is not a solid core (in the sense of some kind of lattice or crystalline structure that we are familiar with), but still dense enough that you would not be able to push through it.

I can’t seem to find the reference though.

My WAG is that it would be a moving mass that you have no hope of moving yourself. Essentially an extremely compressed gas that can apply more pressure than you can.

5

From Nasa’s website:

Model values at center of Sun:
Central pressure: 2.477 x 10^11 bar
Central temperature: 1.571 x 10^7 K
Central density: 1.622 x 10^5 kg/m3

At this temperature and pressure, hydrogen should exist as a plasma. An extrememly thick goo.

6

A very in-depth post, spritle. I must ask, though, was that really all relevant?

Also, as to neutron stars, they’re a superfluid (at least as far down as we can explain them). You could call them a liquid, I guess. The core is a completely different matter, but we can’t really say at this time what that matter is: Gravity and quantum mechanics are both significant way down there, so current theories aren’t up to the task.

7

…so let me restate.

What would it feel like to push on super-dense materials?

Water is more dense than styrofoam but I’ll feel more resistance to poking my finger into styrofoam than I would into water (say I do this slowly so as not add surface tension into the equation…going fast enough water can feel quite hard for a moment as anyone who’s done a belly-flop can attest to).

Does this continue on up to the point where I have super/ultra dense materials? Would that material resist my poking a finger into it or would it separate as easily as water to my intrusion?

8

The outer part of the sun is hydrogen plasma. Next layer in is helium plasma. Then further in, lithium plasma. And so on, through the periodic table, down to the very innermost core, where iron plasma forms. Iron is the bottom of the nuclear energy well. Neither fusion nor fission will get any more energy out of iron.

Plasma means that the nuclei are on their own with the electrons stripped away by the high energy. If I understand Caldazar and Chronos correctly, the iron plasma would be an extremely thick goop, but how could it be solid? Plasma is by definition a different state of matter from solid. It only exists under high energy conditions. So if you could hypothetically exist under those conditions, you’d be a plasma too. (Of course, then you wouldn’t have any “form” that would allow you to push your finger into the stuff to test it.) Could plasma ever be anything other than amorphous?

9

my SWAG…it would feel solid (ignoring heat, any kind of pressure gradient…i.e., there you are at 1 atm and in front of you is this high density material…no thousands of miles of gradually increasing pressure)

A liquid is something that cannot withstand a shear force. Touching the superdense star material is not going to apply enough force to move it, so it will feel solid.