Why can't my headlights shine more than 160 feet in front of me, but stars can emit light that travels allllll the way the fuck to us here on the earth... I understand that on earth, there is atmosphere and whatnot that scatters and stops the light from shining further, but isnt starlight travelling through arguably much more atmosphere to shine all the way the fuck to my eyes? I mean- what the fuck- Why do people believe this shit? Can someone explain to me why I can see starlight from billions of miles away?
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In the case of headlights, you are seeing light reflected and scattered by aerosol particles in the air back into your eyes, and that is a small fraction of the light that goes forward. You, the observer and the light source, are at the same location - the car. In the case of starlight, you are looking directly at the light source.
The intensity of visible light emitted by the Sun at the location of the Earth is about 1000 W/m^2 on a clear sunny day. The distance Sun-Earth is about 1.5x10^11 m. Thus the power of visible light emitted by the Sun is around 2.8x10^26 W. Compare this to a 100-W lightbulb of which only 5% ends up as optical power.