Size Of The Universe

~2 mins read

94b light years

size of milkway, 100k light years

the milkway/universe

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1e5 / 1e11 ~ 1e-6 in dia 

~ 1e-18 in vol

8.317 light-minutes, distance between Earth and the Sun

1 year 8766 hours, 31.5m secs, 500k minutes

sun-earth distance/galaxy

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8 minutes / 100k years  ~ 8 / 1e5 0.5 e5 ~ 16/e10 ~ 1e-9 

~ 1e-9 in dia 

~ 1e-27 in vol 

so the sun-earth distance is like a nanometre for the galaxy

diameter of earth = 0.0425501031 light seconds

100k ly ~ 3e12 light seconds

earth/the galaxy

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4e-2 / 3e12 ~ 1e-14 in dia

1e-42 in volume 

volume of earth/the observable universe 1e-20 in dia 1e-60 in vol

dia of earth = 12 756 km ~ 1e8 m

if the universe diameter was the size of the earth,

the earths dia would be

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1e8 m * 1e-20 = 1e-12 m 

a hydrogen atom’s dia is ~ 1e-10 and its nucleus ~ 1e-15, on the order of a fermi

so if universe was earth-sized, earth would be 1% of an hydrogen atom

then if universe was sun-sized, earth would be the size of an hydrogen atom

1.28 Light Seconds for Earth to Moon

28 000 light-years, sun to the center of milkway

200b galaxies at least

universe 1

100b stars in milkway

100b galaxies in the universe

~ 1e22 stars

dia

uni/milky 1e6

milky/sun 1e12

sun/earth 100

uni/earth 1e20