Things You Were Lied to About Space

People have been lied to about space for centuries.

Although many people believe that space is a vacuum, it is actuallyfilled with materials and objects.

Many myths about space are perpetuated by the entertainmentindustry.

our sun looks nothing like this

it looks more like this

if you've always thought our son was a

bright yellow ball of fire you were

wrong for starters it's not yellow it's

green

sort of

scientists determine the temperature of

a star by the color spectrum it emits

each color has its own wavelength and

astronomers measure those wavelengths to

tell how hot a star is

cooler stars appear red the hottest of

the stars look blue

our sun emits most of its energy at a

wavelength that's close to Green

but because it also emits other

wavelengths all these colors mixed

together and your eyes see this vibrant

mixture as white

that is if you look at the Sun from the

International Space Station from here on

Earth the Sun looks yellow because our

atmosphere is really good at scattering

blue light

and with all that blue wavelength gone

all the other colors combine into yellow

if our star was actually yellow it would

be about 800 degrees Celsius cooler our

Solar System's habitable zone would

shrink and Earth would become a frozen

lifeless Rock

but that's not the only thing you were

wrong about

the Sun is hot but it's not on fire

burning is a chemical reaction of oxygen

fuel

like most stars out there our sun is a

ball of gas mostly made up of hydrogen

and helium it doesn't have much oxygen

in it

instead it works more like a gigantic

nuclear reactor constantly fusing

hydrogen atoms to create helium inside

its core

this process releases enormous amounts

of energy and that's why the sun is so

scorching hot

speaking of setting things on fire let

me tell you about explosions in space

yeah these aren't real

a spaceship can't go down in a violent

blast because there's no air out there

in space

no air means no oxygen and no oxygen

well as you already know means no fire

sorry Star Wars fans

it may seem that there are too many

stars in the night sky for you to count

but actually you can

although scientists at Harvard have

already done it for you

according to the Yale bright star

catalog there are 9110 stars that you

can see from Earth with the naked eye

try to count them all for yourself

movies make it look like you need to be

an extremely skilled pilot to navigate

the asteroid belt but that's not true

the asteroid belt isn't some thick

obstacle course of death

it does have trillions of space rocks

that range in size from space dust to a

quarter the size of the Moon about 100

000 of these asteroids are over one

kilometer wide but they're very spread

out

the asteroid belt between Mars and

Jupiter is

225 million kilometers across

that's one and a half times the distance

between Earth and the Sun

and this spreads the space rocks

millions of kilometers apart it's almost

impossible for a spacecraft to collide

with one if you were thrown out of the

airlock into the vastness of space you

wouldn't turn into a popsicle right away

that's because to freeze there has to be

a heat transfer from space to your body

but heat or cold doesn't travel very

fast in the vacuum of space

your body would freeze but it would take

hours to happen

and by then you'd be long dead from

something else and no you wouldn't

explode in space either

you would inflate though that's because

nitrogen in your bloodstream would

gather into bubbles and puff you up to

double your size

but that's not what's going to kill you

it's the lack of oxygen after 15 seconds

in space your brain wouldn't get enough

oxygen through your blood

and you'd lose consciousness

after two minutes in space your other

organs would start to shut down one by

one

game over

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space seems incredibly cold but it's not

in reality space doesn't have a

temperature at all

temperature is defined by the speed at

which particles move and the amount of

energy they have

in the true vacuum of space there are no

particles to move around

that's why the vacuum is temperatureless

of course outer space isn't a perfect

vacuum it still has particles and

radiation to produce heat

some areas of space are actually really

hot like the space around Stars

but the further away you get from Stars

the more spread out the particles are

making those areas of space pretty

chilly

some dense gas clouds can get as cold as

minus 263 degrees Celsius

Mercury is the closest planet to the Sun

but surprisingly it's not the hottest

it is Extreme though during the day the

surface temperature reaches 430 degrees

and at night it drops to minus 180.

but the most hellish planet in the solar

system is Venus

Mercury doesn't have an atmosphere to

retain all that heat from the Sun

the venusian atmosphere on the other

hand is very thick and it creates a

greenhouse effect

it's like global warming on steroids and

it makes Venus a hot hell with a surface

temperature of about

475 degrees

our entire solar system isn't just

sitting in one spot in our galaxy

it's hurtling through space at 220

kilometers per second

that's seven times faster than the speed

that Earth revolves around the Sun

our solar system takes 230 million years

to make one orbit around the Milky Way

yeah the last time we were in the same

location we are now Earth had one

supercontinent and the dinosaurs were

just starting to roam around

planets do not orbit around the sun

all the things in our solar system are

in balance and even though the sun is

the most massive object in our planetary

neighborhood other planets are

participating in this gravitational tug

of war

instead of orbiting the Sun planets and

moons orbit around a central point

between them and our star

this point is called the Berry Center

for Earth this Berry Center is so close

to the sun's core that there's not much

of a difference but for Jupiter this

point is about 55 000 kilometers away

from the center of the Sun

so the gas giant and the sun are

orbiting each other

Earth appears round from space but it's

actually an irregularly shaped ellipsoid

it bulges at the equator thanks to the

centrifugal force caused by our planet's

spin

as a result Earth is about 43 kilometers

wider at the equator than it is at the

poles

this makes gravity at the Bulge slightly

weaker making it easier to launch

spaceships from the equatorial regions

than from the poles

in space no one can hear you scream

and that's only true to a point

sound needs a medium to travel through

and in space molecules are very far

apart so the sound Fades away before it

can get very far

all the cosmic catastrophes supernovas

and colliding black holes go quiet

before you can hear them but some places

in space have a lot of particles for

sound to travel through

like the hot gas cloud around the black

hole at the center of the Perseus Galaxy

cluster

it has so much gas that you can actually

hear the black hole this is what it

sounds like

thank you you know other planets make

noise too

if you could hear them do you know what

they would sound like

well that's a story

for another

what if