/lit/ - Literature

>>20609906

You know how if you have a lightbulb right next to you you will singe your eyes out but when it’s on the ceiling you’re fine?

The farther you are from something the more dim it, and from said dimming you can calculate your distance from the lightsource as long as you know how bright it is. And we know how bright stars should be since we have one in our backyard.

Now it’s HS physics time: the speed of light is roughly 300 000 km/s, so one lightyear per year. The distance between earth and andromeda is roughly 2,5 million lightyears.

Time=Velocity*speed therefore it took the light 2,5 million years to get to us.