Did you see 1st November (2009) Astronomy Picture of a Day?
linkThis is it:

They say it's an average color of The Universe (named "cosmic latte"), but only this?
Some unanswered questions:
- Is this color also an average color of all observatories?
- Sholud we rename our project to "Comsic Latte Observatories All Over the World"?
- How long astronomers know this color?
- Is it some kind of conspiracy?
- Previous question can be reduced to: what is the very first astronomical observatory painted in that color?