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Stellar Water Fountain
ktulu1115 writes "Space.com writes: An aging star that spits water into space could provide astronomers the clues they need to explain the formation of planetary nebulae, the cloudy remnants of a star's death."
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1. The picture is an artist's rendition (look at the caption under the picture to the right of the article). The article doesn't say how the nebula was observed, but it's entirely possible it was not using visible light at all but IR, UV, XRAY, whatever (I'm no astronomy expert, but I know they don't always limit themselves to the visible spectrum). The water could have been identified from any number of known absorption lines.
2. The water in question here is probably not liquid water. The article constantly refers to the star spewing "water molecules". Although the incredibly hot water coming from a star probably cools enough to liquify, it's still probably not dense enough to form liquid. If you were out there in a spaceship looking at this star, my guess is you wouldn't be able to see these plumes. Sensitive astronomical equipment, however can see things you can't. Again, this is an artist's rendition.
3. Liquid water is actually blue, and not just from the sky. It absorbs red light a little more than it absorbs blue light. A glass of water absorbs too little for you to see, so the water looks clear. 60 ft of water absorbs enough red light that everything you see looks blue or green. A quick google search turned up this link. http://www.sbu.ac.uk/water/vibrat.html The discussion is pretty technical, but about halfway down the page is a nice graph showing water absorbtion vs. wavelength, with the visible spectrum colored in for reference.
4. That said, your point about the sky and reflection is not completely wrong. When you look down at a body of water (as opposed to swimming around under water), most of the light you see is reflected off its surface, and the water will appear similar in color to the sky, regardless of what colors it absorbs. And so, yes, if that were liquid water coming out of the nebula, and that were a real picture, "red" water could still be very easily explained if the nearest source of light were red (like the nebula as it's drawn in the picture).
I hope you're trying to be funny.*
Any H2O molecule is a water molecule, regardless of its state. When I was doing analysis of data looking at a young stellar object, there were definite water absorbtion bands in the spectrum. The temperature of this object was something like 80K, which is well below the freezing point of water, and yet, when it came time to write up the paper, I referred to it as water.
Everybody in the astronomical world does the same. They might call it "water ice"**, but it's always water.
* If you're not, then I weep for the educational system. If you are, then I weep for whoever modded your comment up as "insightful".
** And "ice" doesn't necessarily refer to water ice either. Another example of ice found out there would be methane ice.