Illumination far, far, away from the sun

[DelRioPilot]

So while playing Orbiter, I ended up getting a spacecraft very far away from the sun.

I noticed, that despite the distance, one side of the ship remains illuminated, and the other is dark.

I was also thinking about how Mercury can be just as illuminated by the sun as Neptune -- at least in appearance.

But I was wondering if there ever reaches a point where the sun stops illuminating one side of an object. Say we pushed Neptune further and further away. Would it eventually just look like a sphere engulfed entirely in a dark shadow? I mean, it's not like the other stars of the universe really illuminate the dark side of the Earth.

 

[Quick_Nick]

In real-life, yes. The outer solar system is very dark compared to Earth.
In Orbiter, not in the default graphics client. The DX7 client has constant lighting from the sun everywhere.

Also in real life, the moon illuminates the Earth just slightly (imperceptably) but the stars really do not.

 

[streb2001]

In Orbiter, not in the default graphics client. The DX7 client has constant lighting from the sun everywhere.

Are you suggesting that the DX9 client has an inverse square reduction in light intensity away from the Sun?

 

[Quick_Nick]

Are you suggesting that the DX9 client has an inverse square reduction in light intensity away from the Sun?

I'm suggesting that I haven't used the other clients enough to know. :lol: I believe it is possible, but impractical for a space sim.

 

[asbjos]

Just for the record, the light from the Sun hitting Pluto has one thousand of the energy hitting Earth (in real life, of course). But as Quick Nick says, Orbiter doesn't take distance into account, so you get the same brightness everywhere. But if you sometime plans to make a planet in Orbiter at a great distance from the Sun, you can make it's texture really dark, so that the planet appears dark.

 

[Quick_Nick]

Just for the record, the light from the Sun hitting Pluto has one thousand of the energy hitting Earth (in real life, of course). But as Quick Nick says, Orbiter doesn't take distance into account, so you get the same brightness everywhere. But if you sometime plans to make a planet in Orbiter at a great distance from the Sun, you can make it's texture really dark, so that the planet appears dark.

The problem is, your ship will be very shiny still!

 

[Hlynkacg]

Just for the record, the light from the Sun hitting Pluto has one thousand of the energy hitting Earth (in real life, of course). But as Quick Nick says, Orbiter doesn't take distance into account, so you get the same brightness everywhere. But if you sometime plans to make a planet in Orbiter at a great distance from the Sun, you can make it's texture really dark, so that the planet appears dark.

True but due to the magic of the human eye you might not notice. Our eyes use only a small percentage of the total amount of light available to see. The amount light hitting pluto (in candle power) is still equivilent to bright interior lighting here on earth.

The only real difference from a human perspective would be the lack of sun-burn and reduced chance of blinding.

 

[asbjos]

The problem is, your ship will be very shiny still!

Close your eyes and everything will be dark, just as it should be :lol:

 

[T.Neo]

The eye can adapt to various levels of light, though it obviously does have its limits. Indoor lighting is far dimmer than direct lighting from the Sun, yet we can see fine. And even moonlight- which is very dim compared to artificial lighting- is quite useful for vision, especially if one's eyes are sufficiently adapted to that low level of light.

Using Celestia, which calculates the apparent magnitude of Sol (or other stars) at various distances, we find that even out at Sedna, which is something like 87 AU from Sol right now, the apparent magnitude of the Sun is -17.05. The magnitude scale is logarithmic, so the sun at Sedna is over 50 times brighter than the full Moon on Earth. At Neptune, the sun is -19.36, or over 400 times brighter than the full Moon. At Saturn, the sun is -21.79; over 4000 times brighter than the full Moon.

So you'd be able to see out at the outer planets. What things might look like is another matter, but you'd definitely see stuff.

 

[DelRioPilot]

Good answers. Makes perfect sense logically.

So what about some sunless planet roaming through the depths of deep space? Would the human eye really be able to make out many of its features if you got close enough to it?

 

[Hlynkacg]

Good answers. Makes perfect sense logically.

So what about some sunless planet roaming through the depths of deep space? Would the human eye really be able to make out many of its features if you got close enough to it?

How well can you see on a moonless night?

That's your answer.

 

[T.Neo]

You can if you use image-intensifier gear.

 

[Quick_Nick]

How well can you see on a moonless night?

That's your answer.

If this drifting planet is magically inhabited and affected by the same light sources that Earth is.

 

[Hlynkacg]

If this drifting planet is magically inhabited and affected by the same light sources that Earth is.

If you mean stars

well yes.

 

[T.Neo]

There are other light sources on Earth, much to the disdain of astronomers. If artificial lighting were present, it might be visible.

 

[statickid]

but there are also places with very little artificial light, such as a desert or out on the open ocean. I have seen Sirius casting a crazy bright reflection on the pacific