Celestia Forums

I'm wondering how a real typical nebula would look like at VERY close range, or from the inside. How luminous should it be for the human eye ? How contrasted and colorfull should it be ? Astronomers out there, any idea ? T00fri ? Selden ? Evil Dr. Ganymede ?

Sadly, the brightness of a nebula is the same no matter how close you are to it. Although the total light increases as you get closer, it's spread out over a larger area on the sky. The two effects exactly cancel one another

So all those "artisitc" images we can find on the various NASA web sites, about exoplanets with nebulae as backround, are all BS ? Sad.

selden wrote:Sadly, the brightness of a nebula is the same no matter how close you are to it. Although the total light increases as you get closer, it's spread out over a larger area on the sky. The two effects exactly cancel one another

How about if stars are illuminating it though? Wouldn't you get nebulosity visible aroun those regions?

Cham,

Think of such pictures as long exposures. Or "artists' impressions."

EDG,

The brightness (number of photons per second) per unit area will be unchanged. Remember that the reason stars don't burn (tiny) holes in our retinas like the sun does is that their images are blurred out over a much larger area than they "should be" because of diffraction and poor focusing.

Added slightly later:
With good seeing conditions, some nebulosities should be barely visible, just like the zodical light in our solar system can just barely be seen. It's a dust cloud with similar density.