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Earth is a pale blue dot when viewed from space. Now astrobiologists have worked out the likely colours of Earth-like planets orbiting other stars

Mantis shrimp seem to have 12 types of photo-receptive sensors - but this does not really improve their ability to discriminate between colors. Speculation is that they serve as a form of pre-processing for visual information: the brain does not need to decode full color information from just a few channels which would would allow for a smaller brain. I guess technologically the two extremes of light detection would be RGB cameras which are like our eyes and offer good spatial resolution, and spectrometers which have a large amount of color channels but at the cost of spatial resolution. It seems the mantis shrimp uses something that is somewhere between RGB cameras and spectrometers. Could there be a use for this in space?

> RGB cameras which are like our eyes ...apart from the fact that the spectral response of the eyes is completely different from "RGB" cameras (http://en.wikipedia.org/wiki/File:Cones_SMJ2_E.svg) ... and that the eyes have 4 types of light-sensitive cells, not three (http://en.wikipedia.org/wiki/File:Cone-response.svg) ... and that, unlike cameras, human eye is precise only in a very narrow centre region (http://en.wikipedia.org/wiki/Fovea) ...hmm, apart from relying on tri-stimulus colour perception it seems human eyes are in fact completely different from "RGB cameras" :-) OK sorry for picking on this - that's just the colour science geek in me :-) Now seriously, on one hand the article abstract sounds very interesting, but on the other the statement "Why use 12 color channels when three or four are sufficient for fine color discrimination?" reveals so much ignorance to the very basics of colour science that I'm completely puzzled - in the end, it's a Science article so it should be reasonably scientifically sound, right? Pity I can't access full text... the interesting thing is that more channels mean more information and therefore should require *more* power to process - which is exactly opposite to their theory (as far as I can tell it from the abstract...). So the key is to understand *what* information about light these mantises are collecting and why - definitely it's not "colour" in the sense of human perceptual experience. But in any case - yes, spectrometry has its uses in space :-)

Not easily digestible piece of esa document, but to prove Paul's point. And yes, they have already planned to train neural networks on a database of different water types, so that the satellite figures out from the combined retrieval of backscattering and absorption = f(λ) which type of water it is looking at. Type of water relates to οptical clarity of the water, a variable called turbidity. We could do this as well for mapping iron fertilization locations if we find its spectral signature. Lab time?????

Several recent papers on biomimetics and photonics, including works on structural colours, radiation shielding, spiders and more.

including one for Tom: Structural color and its interaction with other color-producing elements: perspectives from spiders Bor-Kai Hsiung ; Todd A. Blackledge ; Matthew D. Shawkey [+] Author Affiliations Proc. SPIE 9187, The Nature of Light: Light in Nature V, 91870B (September 8, 2014); doi:10.1117/12.2060831

I assume that our fancy colour printer also have this "feature" ... 

interesting research - could we put this in context with curiosity cloning? 200 ms is probably measurable ....

In a new exhibition titled Beautiful Science: Picturing Data, Inspiring Insight [bl.uk], the British Library pays homage to the important role data visualization plays in the scientific process. The exhibition can be visited from 20 February until 26 May 2014, and contains works ranging from John Snow's plotting of the 1854 London cholera infections on a map to colourful depictions of the Tree of Life.

UK researchers say they have achieved data transmission speeds of 10Gbit/s via "li-fi" - wireless internet connectivity using light. The researchers used a micro-LED light bulb to transmit 3.5Gbit/s via each of the three primary colours - red, green, blue - that make up white light. This means over 10Gbit/s is possible.

anything happening on this since 3 years?

yes it seems like. most of it seems however directed toward understanding this effect, and not toward applications. But i'm still convinced that we could find many very interesting applications !!! a few references from ADS: 1 2011PhRvA..83f3807B 1.000 06/2011 A E X R C U Brida, G.; Chekhova, M. V.; Fornaro, G. A.; Genovese, M.; Lopaeva, E. D.; Berchera, I. Ruo Systematic analysis of signal-to-noise ratio in bipartite ghost imaging with classical and quantum light 2 2011PhRvA..83e3808L 1.000 05/2011 A E R U Liu, Ying-Chuan; Kuang, Le-Man Theoretical scheme of thermal-light many-ghost imaging by Nth-order intensity correlation 3 2011PhRvA..83e1803D 1.000 05/2011 A E R C U Dixon, P. Ben; Howland, Gregory A.; Chan, Kam Wai Clifford; O'Sullivan-Hale, Colin; Rodenburg, Brandon; Hardy, Nicholas D.; Shapiro, Jeffrey H.; Simon, D. S.; Sergienko, A. V.; Boyd, R. W.; Howell, John C. Quantum ghost imaging through turbulence 4 2011SPIE.7961E.160O 1.000 03/2011 A E T Ohuchi, H.; Kondo, Y. Complete erasing of ghost images caused by deeply trapped electrons on computed radiography plates 5 2011ApPhL..98k1115M 1.000 03/2011 A E R U Meyers, Ronald E.; Deacon, Keith S.; Shih, Yanhua Turbulence-free ghost imaging 6 2011ApPhL..98k1102G 1.000 03/2011 A E R C U Gan, Shu; Zhang, Su-Heng; Zhao, Ting; Xiong, Jun; Zhang, Xiangdong; Wang, Kaige Cloaking of a phase object in ghost imaging 7 2011RScI...82b3110Y 1.000 02/2011 A E R U Yang, Hao; Zhao, Baosheng; Qiu

nice article ... though the colouring used seems a lit awkward to me ...

Characterizin bionanophotonic structures

A new and amazing method for neuron staining.