How bright would sun be on Pluto?

depends, like where is it on its orbit i think... lol

The Sun would be 1600 times fainter on Pluto than it is on the Earth.

First, you need to understand how an object like the Sun, or any source of light, dims with distance. The Sun emits light in all directions, so as you get farther away from the Sun, that light gets spread out. Imagine a sphere perfectly encasing the Sun right at its surface. Each square centimeter has a certain amount of light passing through it. If I double the size of the sphere, there’s a lot more surface area to that sphere, but the total amount of light passing through it hasn’t changed. Therefore the amount of light passing through each square centimeter has dropped. Since I doubled the sphere’s diameter, I can figure out how much its dropped, too!

The formula for the surface area of a sphere is

Surface area = 4 × π × radius 2

If we double the size of the sphere, everything on the right side of the equation stays the same except for the radius, which is now twice as big. Therefore the area increases by 22 = 4. So the light passing through each square centimeter of the bigger sphere drops by a factor of four. Someone standing on that sphere would see the Sun being 1/4 as bright as if they were on the surface. (This is known as the inverse square law.)

If I make the sphere ten times bigger, the area goes up by 10 × 10 = 100 times, and the brightness drops by 100. You get the picture.

So now we’re ready to figure out how bright the Sun is from Pluto!

The Earth orbits the Sun, on average, at a distance of about 150 million km. Pluto has a very elliptical orbit, but has an average distance of about 5.9 billion kilometers, or roughly 39 times the Earth’s distance from the Sun. Using the method above, the Sun must be 392 = about 1500 times fainter, or more grammatically correctly, 0.00065 times as bright. That’s pretty faint!

Or is it? Well, let’s compare that to how bright the full Moon looks from Earth. To us here at home, the Sun is about 400,000 times brighter than the full Moon, so even from faraway Pluto, on average the Sun would look more than 250 times brighter than the full Moon does from Earth!

Pluto’s orbit is also highly elliptical, stretching from 4.4 billion km to just over 7.3 billion km from the Sun. Doing the math again, that means the Sun goes from being 0.0012 to 0.0004 as bright as it is from Earth: a range of roughly 150 to 450 times as bright as the Moon from Earth. That’s a change in brightness by a factor of three!

Still, given that you can read by the light of the full Moon, obviously the Sun from Pluto is still pretty dang intense. It would hardly look like just any other star: it would greatly outshine everything else in the sky. Painful to look at, most likely.

(Modified from DiscoverMagazine.com)

This is a link to an artist's conceptualization, based on available data. The work includes the moon, Charon, and the sun as a bright star.

http://en.wikipedia.org/wiki/File:ESO-L._Cal%C3%A7...

It would just look like a bright star in a very dark sky full of stars.

Barely discernable from any of the other faint points of light in the sky.

about -19 magnitude

Its alot smaller and dimmer than it is here on Earth.

-It'd be the Brightest Star in a Sky- filled with 5 Moons... ;)