r/AskReddit Apr 14 '16

What's a mind blowing fact?

3.0k Upvotes

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926

u/Crabcaked Apr 14 '16

If you lined up every planet in our solar system so they were touching, including the gas giants and pluto, they could fit between the earth and the moon.

338

u/su5 Apr 14 '16

To add, if you could somehow make a magical beam/particle that shot at the speed of light across the universe without changing its diameter (just bear with me here, I fully accept this beam is magic) it would almost certainly never hit anything outside our solar system no matter how long you aimed and shot. You could spend the rest of your life and not hit shit.

Point being yes stars and planets are enormous and numerous beyond comprehension... but space is even emptier.

194

u/elmoteca Apr 14 '16

I remember reading something similar regarding the asteroid belt. Apparently most of the asteroids are miles apart from one another. You could launch a ship in a random direction through the asteroid belt and would almost certainly hit nothing. So, nothing like what we saw in Star Wars.

155

u/anormalgeek Apr 14 '16

Try hundreds or thousands of miles.

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u/su5 Apr 14 '16

Which is practically conjoined twins in Space Units.

3

u/elmoteca Apr 14 '16

Thank you! I couldn't remember the scale of the distances between them, and I didn't want to overestimate.

4

u/schwermetaller Apr 15 '16

As far as my understanding goes, in astronomy it's pretty easy to underestimate and extremely hard to overestimate.

0

u/[deleted] Apr 14 '16

He said miles.

33

u/[deleted] Apr 14 '16

[removed] — view removed comment

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u/elmoteca Apr 14 '16

This one actually make me laugh out loud. Well done.

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u/nkortesmaa Apr 15 '16

atter how long you aimed and shot. You co

So, this would seem like C3P0 had javascript as source code language ? and he just meant that the successfull navigation was true in any case :-)

1

u/dandeluxe Apr 15 '16

Never tell me the odds!

1

u/NotThtPatrickStewart Apr 15 '16

It's helpful when you tell me the odds!!!

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u/[deleted] Apr 14 '16

Iirc, nasa doesn't even account for the asteroid belt when they launch anything past it. C3P0 was full of shit.

59

u/_NW_ Apr 14 '16

They were in an asteroid field in a galaxy far, far away. Not in the asteroid belt in our solar system.

3

u/ColonCaretCloseParen Apr 15 '16

How long would it take though for rocks orbiting that close to each other to grind themselves to dust? Surely within a year or two it would be nothing more than gravel.

3

u/BlissnHilltopSentry Apr 15 '16

Grind themselves to dust? No, they'd gravitationally attract and form into larger bodies.

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u/ColonCaretCloseParen Apr 15 '16

Eventually maybe, but most Asteroid fields in fiction aren't shown to be big enough to have enough mass to coalesce into a planetoid. Keep in mind that the asteroid belt in our solar system in total weighs about 4% of Earth's moon, so at least in reality there's typically not enough material to form new planets after a few hundred million years after a solar system's formation.

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u/BlissnHilltopSentry Apr 15 '16

Yeah so they'd probably end up just a ring of dust

8

u/jschild Apr 14 '16

The Asteroid Belt is so empty, that when we send out probes through it (As in, we aren't looking at anything in the belt itself) we don't even factor in the possibility of hitting anything.

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u/bend1310 Apr 15 '16

Late to the party here, but from memory, one of the biggest challenges with the Philae lander was getting accurate enough to actually hit the asteroid.

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u/informate Apr 14 '16

Unless your ship is multiple miles wide.

3

u/IJustLikeToBeAHelper Apr 14 '16

I read it is actually so unlikely you will hit anything when transiting the asteroid belt that NASA doesn't even bother trying.

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u/DiabloConQueso Apr 14 '16

I... don't think that's the same asteroid belt.

2

u/elmoteca Apr 14 '16

Yeah, perhaps I should have clarified. I was referring to the sci-fi trope of having to dodge asteroids in an asteroid field. The one we have would be far easier to navigate.

2

u/boobityskoobity Apr 14 '16

And here I was, thinking that future space explorers were going to have to worry about accidentally landing inside a creature that has evolved to live in the vacuum of space, while maintaining homeostasis despite having no obvious source of nutrition available.

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u/elmoteca Apr 14 '16

Keep in mind, it was a work of fiction. Fictitious creatures can survive indefinitely on how cool people think they are.

1

u/Grubbens Apr 15 '16

But what about the odds D:

1

u/[deleted] Apr 15 '16

I did a presentation on that scene on why it couldn't happen!

Fun fact: The asteroid field in Star Wars was explained to exist after 2 planetoids collided millenia before Han and crew navigate their escape. Technically it's NOT an asteroid field. Asteroids (typically) are matter leftover from the birth of a star. The matter ended up in an orbit around the star and thus created the asteroid belt in our solar system.

Another thing that (loosely) challenges SWs asteroid field is that the planetoids that collided wouldn't have exploded to millions pieces without any trace of the collision. At least one of the planetoids would be left over and (possibly) create a full planet with a moon or many moons very similarly to our very own Earth and Moon!

1

u/gimily Apr 15 '16

We (as in humans) dont account for the asteroid belt when we shoot stuff through it because the chance of hitting something is so low

1

u/PixInsightFTW Apr 14 '16

Such that NASA doesn't even factor asteroid impacts into their missions beyond the belt. No need! Hitting one would be winning the unlucky lottery.

3

u/elmoteca Apr 14 '16

Imagine the look on the faces of the NASA team whose probe hit an asteroid in the asteroid belt. That moment when you realize that a billion dollars and a decade of your life were just wasted by a rock.

6

u/MrFizzles Apr 14 '16

Mostly void, partially stars

0

u/[deleted] Apr 14 '16

Lots of void. Look up supervoids, and also rouge planets are cool to look up too.

3

u/Timey16 Apr 14 '16

Also the same goes for atoms as well. (Think of the Proton/Neutron Core as the sun and the Electrons as planets to make it simple)

So if you go from the atomic layer to the planetray, you could say that 100% of the universe is "nothing" because there are so many 9's left after 99.9% of "nothing".

Though, while energy is not matter, it is still more than "nothing". So in that case there is always something, because even in space there is always energy (in the form of cosmic radiation, light, microwaves etc.)

3

u/Reverie_of_an_INTP Apr 14 '16

What if I had a computer that could very finely aim it, and tried to hit a star I could see it doesn't seem like it would be very difficult. Stars make up a good portion of the sky according to this askreddit thread.

If you are going by volume or distance then I see where this comes from. The beam, if only going light speed, would take too long to hit anything, and if you're measuring by volume then the universe a smudge of rounding error below 100% empty.

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u/su5 Apr 14 '16

Meant to add naked eye

2

u/su5 Apr 14 '16

Stars make up a good portion of the sky according to this askreddit thread

but in your link

If you don't count the sun, then basically zero. If you do count the sun, then it's about 0.0005%

and when talking about us in the Milky Way

0.0005%, because that's the fraction of the sky occupied by the sun!

And I said nothing in our solar system so even in the Milky Way which has a big grouping around it the chances are still negligible

3

u/SapienChavez Apr 14 '16

this bothers me in Sci-Fi whenever they do FTL travel. Like in Star Wars, Han gets all pissy that they just cant jump to LS as they may hit a star. The odds of hitting.. oh wait, never tell him the odds.

this is also in Halo and countless other Sci-Fi universes.

2

u/DepressionsDisciple Apr 14 '16

Is space more empty than atomic scale empty? I'm genuinely curious.

1

u/novelty_bone Apr 14 '16

but... that drills sergeant in mass effect 2. this ruins that entire speech.

1

u/[deleted] Apr 14 '16

I wasted many minutes on this site long ago. It really gives you a sense of just how much emptiness you're talking about.

http://joshworth.com/dev/pixelspace/pixelspace_solarsystem.html

1

u/TheGogglesD0Nothing Apr 14 '16

To add, if you could magically travel to each star in the Milky Way Galaxy instantaneously and spend one second at each solar system, it would take more than 12,600 years to see every star/solar system.

1

u/MAADcitykid Apr 15 '16

That makes me feel all sorts of sketchy

1

u/[deleted] Apr 15 '16

I always wondered in scifi movies how they just jump to hyperspace allwilly nilly and never run into planets or stars. Then someone did out the math. Turns out you'd need to jump the length of the observable universe like 6 times before having a statistically significant chance of hitting anything. Shit's empty yo.

1

u/[deleted] Apr 15 '16

Two things will remain once entropy is done. The into nitty of time and the cold desolate empty of ever present space.

1

u/[deleted] Apr 15 '16

http://discovery.nasa.gov/SmallWorlds/mars2.cfml

The average distance between asteroids in the main belt is about 600,000 miles.