Why are stars fuckhueg and planets not?
Also, how do they even estimate the sizes of these stars?
there's more hydrogen in the universe than other elements. what else you fucking idiot? jesus how is this a question? think about it; the progenitors of other elements are these stars. when they exceed a certain size they reach a critical phase that prevents an accretion disk of a large enough scale that could produce fuckhuge exoplanets.
>>7971003
The rich get richer. The biggest object around tends to accumulate more mass than other nearby objects, making it even bigger, and even for likely to pick up mass, and so on. Also with the really big ones a lot of their volume isnt particularly dense
>>7971009
>there's more hydrogen in the universe than other elements
That doesn't tell me shit.
> what else you fucking idiot? jesus how is this a question?
Tell me how to price a European stock option. Speak with me in German. Write some code in C#. Getting the point dumbass?
>when they exceed a certain size they reach a critical phase that prevents an accretion disk of a large enough scale that could produce fuckhuge exoplanets.
What?
>>7971013
As in, from just pulling shit in because magnets and random asteroids hitting them?
Why aren't some of these huge objects cold / "dead" though?
A question. A star needs to be composed of certain elements to start fusion, right? So are there bodies out there that are the size of stars that DON'T do fusion but still have planets and stuff orbiting them?
>>7971028
no. brown dwarfs wouldn't be capable of forming a disk.
>>7971028
>Stars with 8-11 stellar masses can fuse silicon. So a rocky planet would need millions of times the mass of the Earth before it would have that kind of pressure and temperature.
>So you could get a situation where you have more mass than the Sun in a rock flavored world, and it wouldn’t ignite as a star. It would get pretty warm though.
http://www.universetoday.com/115320/could-a-planet-be-as-big-as-a-star/
What makes huge shit hot?
>>7971032
What's with you and disks?
>>7971032
Is it not possible, as in physically impossible for a structure the size of the Sun to be made out of rock?
>>7971039
could you just imagine flying through space and you start getting pulled in by a big dark structure you can't see? terrifying
there probably aren't any just because metals are so much rarer in the universe, plus the volume condenses as it gets bigger so it would take a shitton
imagine hypothetically an earth as big as the sun though... we'd probably still be claiming territories in unknown regions and you'd have to take space shuttles to get anywhere fast.
>>7971070
>If it's not already a thing
Well, with gravity waves having been observed, maybe we'll discover a method to construct a gravometer to conduct gravimetric readings for asteroids and other rogue bodies.
>>7971016
Yeah from just plling in whatever random shit is floating around in space. What do you mean cold and "dead"? Its rock, ice and gas
>>7971039
>What makes huge shit hot?
Pressure, thats it
>>7971003
Those stars are big, but they're bigger than our entire solar system??
Rigel and Aldebaran are still relatively small stars. See pic.
(btw VY Canis Majoris is still only the 8th largest _known_ star.)
>>7971003
More mass for dem programs
more hydrogen for dem fusion
planets lame but they had enough mass accumulate to make them what they are today (as opposed to the mess that is the asteroid belt)
those atoms were lucky they became a fuck huge star and not some candy-ass that masturbates to hentei
>>7971148
Here's a comparison with the largest known star UY Scuti.
(NML Cygin might be bigger than UY Scuti but we don't know yet.).
>>7971162
Here's a comparison to the Sun.
>>7971013
That's not fair.
>>7971172
Honestly these pictures do nothing for me. I don't have a response, really. I mean, just looking at something like the Burj Khalifa already strains my mind. I cannot adequately comprehend the size of the earth, much less Jupiter, much less the Sun, MUCH less that star you posted. It's neat in a purely scientific way though.
>>7971181
Here's what put things in perspective for me.
>>7971179
Reality generally isnt. Unstable equilibrium's dont care about your feelings
>>7971181
I just did and it's fucking scary.
>>7971009
in what models do you choose to work ?
>>7971009
Disks dont form around stars, stars form in the centre of disks
>>7971003
Elements heavier than hydrogen are rare and thinly-spread enough in the universe that anything that fuckhueg *has* to be mostly a big ball of gas - there simply never enough rock in the same place to make anything bigger than a planet.
We can estimate star sizes because a lot of them are close enough or big enough that large telescopes can actually resolve them as discs with a distinct diameter, and for others we can guess because examination of nearby stars tells us that stars with such-and-such color and age and whatever tend to be such-and-such big.
>>7971039
>What makes huge shit hot?
Surface-to-volume ratio. The bigger something is, the more heat gets trapped inside it, because compared to the amount of hot stuff inside there's less surface to radiate it away.
So stuff gets hot from the initial energy of gravitational collapse - a cloud of rocks and dust collapsing into a planet releases a lot of gravitational potential energy, and because big things hold heat well it takes eons to cool off. About half of Earth's inner heat is left over from formation.
Also, rocks are naturally tiny tiny heat sources because of the decay of small amounts of radioactive isotopes; cluster a planet's worth of rocks together and enough heat gets trapped inside that it adds up to a lot. That's the other half of Earth's internal heat.
Also, gases heat up when compressed. Guess what gravity does to a big ball of gas!
And of course, if you squeeze fusion fuel hard enough (say, from being at the center of a very large object) and get it hot enough (see previous point about compression), then it will begin fusing and generate a LOT of heat, which is then trapped inside of a star's bulk. (Per cubic meter, the Sun puts out less energy than a decomposing compost heap; the Sun just has a lot of cubic meters.)
>>7971223
>We can estimate star sizes because a lot of them are close enough or big enough that large telescopes can actually resolve them as discs with a distinct diameter
I don't think this is true. The Hubble Space Telescope has a diameter of 2.4 meters. The minimum angle that can be resolved for a telescope that is diffraction limited (ie space telescopes) can be found using this equation: [math] \theta [arcseconds]=.25 \frac{ \lambda }{D} [/math] . For 500 nm light, we can resolve a minimum of .052 arcseconds.
https://en.wikipedia.org/wiki/List_of_stars_with_resolved_images
According to this wikipedia page, the largest angular diameter stars are 50 milliarcseconds, which is under our resolution limit. For shorter wavelengths I guess it would just barely be possible to resolve a disk for some stars, but still saying most stars is a bit of a stretch. For telescopes larger than Hubble, the resolution would be better except they are all limited by the atmosphere. Adaptive optics can make this limit go down but this is at the forefront of physics and we've been able to estimate the size of stars for quite some time before adaptive optics were a thing.
The real way we know a stars size is by the Stephen Boltzmann Law. We measure the intensity of a star and it's distance via parallax and then we can calculate the luminosity. We know it's temperature from the peak wavelength using spectroscopy. This gives us the surface area of the star and thus its radius and size.
>>7971016
Like a black hole?
a star is a big ball of gas compressed together by gravity. the center 20% of its diameter is occupied by its core and that is where 99% of the nuclear fusion happens. The fusion is like an enormous never ending nuclear bomb, but all that heat and light energy has to pass through the rest of the star. All the material in that layer is mostly reserve hydrogen fuel that hasnt had a chance to react in the core yet.
Why is the nuclear fusion in the center of a star so slow at using up its hydrogen? I thought explosive nuclear chain reactions happened pretty fast
>>7971172
Why does it not collapse into a black hole?
Also your mother's dildo.
>>7971549
Because the explosive force of the nuclear reaction in the core pushes outwards against the inward force of gravity from the rest of the star
>>7971223
We can see their diameter, but how do we know how far away they are?
>>7971549
Because its still bigger than its schwartzchild radius
>>7971141
Not at all. Aldebaran has a radius of about 3.6x10^7 km, which are about 0.24AU, or in other words, just about a quarter of the distance between Earth and the sun. Space is really fucking big.
http://joshworth.com/dev/pixelspace/pixelspace_solarsystem.html
>>7971003
We'll use your mom as an analogy.
She was a a thin qt in her youth.
Beta orbiters started to orbit her, until they collided with her; this increased her mass so much she became gassy giant slob.
This kept happening until every speck of dusk that enjoyed her company ended up colliding with the dirty slut.
Then she started reaching out more and interacting with even larger systems of fat sluts and betas, who affectionately called her a dwarf to make her feel small.
So she continued to eat the fuck out of everything in her ever increasing area of influence until she began to buckle under her own weight, thus she was named a star. She will be a supernova when she fully collapses and explodes from the sheer force she generates by being a fat fuck becoming uncreasingly unstable, leaving nothing but the scarred and battered black hole she calls a vagina or the remains of her fat ass.
TL;DR don't ask me why your momma is so fat
>>7971016
Tl;dr:
https://www.youtube.com/watch?v=RQWksKNrJm0
>>7971549
Fusion and thermal pressure push out hard enough and the core isn't yet a critical mass of dense unfusable material
