Earthshine (Moon NightTexture)

Orphu of Io · Post #1by **Orphu of Io** » 20.01.2008, 15:27

I was considering using a NightTexture for the moon to simulate earthshine. Perhaps something like the following:

That is just a rough idea of what I had in mind and the brightness has been exaggerated for illustrative purposes. Do you think this is a good idea or have any suggestions?

BobHegwood · Post #2by **BobHegwood** » 20.01.2008, 16:41

Well now, that's an interesting idea...

Does the Earth's reflective light really have a noticeable effect on the
Moon though? Just curious. Never even occurred to me that this
could even happen. No surprise there, I know. :wink:

Orphu of Io · Post #3by **Orphu of Io** » 20.01.2008, 16:53

The effect is subtle but it is visible to the naked eye- especially around the new moon phase.

http://en.wikipedia.org/wiki/Earthshine

The trick will be getting the right brightness and hue for the texture. I'm still not sure if it's worth the trouble though.

Johaen · Post #4by **Johaen** » 20.01.2008, 17:23

I agree that it's an interesting idea. Just recently (just after the most recent new moon), I look up in the sky and was surprised at just how visible the Earthshine was on the moon, even in the middle of a city. I would agree though that the hardest part would be getting the brightness just right. I assume that the far side of the moon would be completely black in the night texture, so that it doesn't show up in it's night?

Orphu of Io · Post #5by **Orphu of Io** » 20.01.2008, 19:40

This is my first attempt.

With Earthshine:

Without:

Download:
http://orphuofio.sitesled.com/textures/EarthShine.zip

Extract the zip in your extras directory.

Johaen wrote:I assume that the far side of the moon would be completely black in the night texture, so that it doesn't show up in it's night?

That's correct. The areas of the moon which are not visible from earth are black.

Fightspit · Post #6by **Fightspit** » 20.01.2008, 20:31

Very Nice !

danielj · Post #7by **danielj** » 21.01.2008, 01:30

Sorry,but I don??t think this is very useful.
The Earthshine can be simulated simply by toggling Ambient Light Medium.The Moon only become dark in the crescent phases,if you put the Ambient Light off.
It??s pretty,but not a great deal.I will try in moon eclipses,though...

danielj · Post #8by **danielj** » 21.01.2008, 01:49

Unfourtanetelly,every time I try to find a lunar eclipse,Celestia locks down.Should I report it in bugs?I am using Celestia 1.5.0 pre5

Orphu of Io · Post #9by **Orphu of Io** » 21.01.2008, 02:50

danielj wrote:Sorry,but I don??t think this is very useful.
The Earthshine can be simulated simply by toggling Ambient Light Medium.The Moon only become dark in the crescent phases,if you put the Ambient Light off.
It??s pretty,but not a great deal.I will try in moon eclipses,though...

Increasing the ambient light increases the brightness of the entire moon- and every other planetary body, not just the night side of the moon which faces the earth. That's not really a very good simulation of earthshine.

Tuefish · Post #10by **Tuefish** » 21.01.2008, 07:19

Orphu, I think you have a point, however, you should make the night-texture much darker, so that it is just barely visible.

Hungry4info · Post #11by **Hungry4info** » 21.01.2008, 20:53

Burying a type B star into the Earth, I get a somewhat nice planetshine effect, but a rather nasty Earth halo. Adjusting the visual magnitude of the B star would adjust the brightness of the earthshine effect.

Orphu of Io · Post #12by **Orphu of Io** » 22.01.2008, 19:12

I've uploaded a darker texture. Use the same download link.
http://orphuofio.sitesled.com/textures/EarthShine.zip