Talk:Jet d'Eau

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Why do we need a citation on seeing the fountain from 10 km up? I've seen it myself, as can anyone flying into Geneva. You can even see it on Google Maps, it is awesome. I am removing the "citation needed" thingy. --WiseWoman 12:11, 4 March 2007 (UTC)

See Wikipedia:Attribution. "I've seen it myself" is not a good enough source for a fact to be cited in Wikipedia. --Mathew5000 17:45, 4 March 2007 (UTC)

A 140m long object from a distance of 10km would have an angular diameter larger than the moon (half a degree). Even allowing for the shape of the fountain (it is not a disc), and having a viewing angle of 45 degrees downwards, say, giving a distance of around 14km, I would be surprised if the fountain is not visible from 10km up under a wide range of viewing conditions, particularly given its motion and contrast of the water spray against the relatively dark water background (when sun direction is appropriate, eg no specular highlight is on the flat water). Under ideal conditions far smaller objects are visible from cruise altitude (eg a bus on a road). For more information, read an article on visual acuity, vision, airborne survellience, search and rescue, or just get on an aircraft! :) What citation could be provided? Perhaps a scientific study showing that 9 out of 10 passengers with window seats were able to see the fountain on a particular day? Any photo could be dismissed as not being representative of human vision. 159.153.156.60 09:46, 3 July 2007 (UTC).

PLEASE add citations to this article if you have any. I came here to clean up the several-month-old uncited tags, but if I do, there won't be much of an article left. Please add cites to anything tagged that you want kept. Alvis 04:44, 11 September 2007 (UTC)

I realize that the sign next to the Jet d'Eau says that water is being pumped to an altitude of 140 meters. However, I have to admit I doubt this number. I live in Geneva and have gone to the Jet d'Eau many times and I have never seen it being that high. Of course my vision could be wrong, but if one assumes that a person standing next to the Jet'd Eau is 1.80m , then the water would have to be almost 80 times the height of the person. And I'd say it is roughly half that number. Is it possible that the height of the Jet'd Eau varies and that it only reaches maximum height under certain conditions? If so, the paragrpah should be changed to "Five-hundred litres (132 gallons) of water per second are jetted to a maximum altitude of 140 metres" (Timoluege 14:15, 2 August 2007 (UTC))

Simple mechanics lets you calculate that a projectile launched at 200kmph would reach a maximum height of 157.7m in the absence of air resistance, so a height of 140m is sensible. The figure of 200kmph is widely documented... - Zephyris Talk 16:03, 26 January 2008 (UTC)

Deleted the "citation needed" reference in the trivia section since the volume of Lac Leman (88.9 billion cubic meters) and the flow rate of the jet (0.5 cubic meters per second) are known, making this statistic calculable by trivial arithmetic. 85.1.180.131 16:25, 7 October 2007 (UTC)

[edit] Overzealous "citation needed"

Removed the citation needed tag for the quantity of water in the air at any time, this is trivial mechanics to calculate.

Many of the other statements are easily supported by a Google search for "Jet D'Eau", I have added references for three statements from the first Google result. In the future try to find references, not simply mark them as "citation needed". - Zephyris Talk 15:25, 26 January 2008 (UTC)