Wikipedia:Reference desk/Archives/Science/2020 February 27

= February 27 =

Location of Fukushima reactor
I've been trying to find information regarding the location of the Fukushima Daiichi Nuclear Power Plant, mainly why it was built in that particular location. Currently, my best guess is that there wasn't strong opposition to the plant in that location and the Sea of Japan provided a suitable cooling source, but it's been a struggle to find any reliable sources. Any ideas? 5225C (talk) 06:32, 27 February 2020 (UTC)
 * On the coast, you mean? Nuclear reactors were often built on coastlines and riverbanks because the designers assumed a catastrophic breach would be more likely to be washed away than could be accomplished from an inland site. While there may be merit to that idea in general, a catastrophic meltdown will still deposit the worst contamination in a literally melted cavern under the reactor core, surrounded by molten steel and concrete, usually without any real chance to wash it into the water. Seawater brine can't be used as a nuclear reactor coolant directly, because it's corrosive and difficult to filter, but it can be used to carry away heat from heat exchangers in cooling ponds, or in Fukushima Daiichi's case, directly on the coastline. This journal article suggests that its siting and hazard studies prior to construction were severely flawed to begin with. This article (in Japanese) covering the court case outcomes, is said to describe the duty of care that TEPCO observed in siting the plant as less stringent than that required of an ordinary automobile driver, because the company, regulators, and their PR agencies had perpetuated a "myth of safety" squelching legitimate questions about risks with an onslaught of misleading claims and attitudes about the likelihood of accidents. EllenCT (talk) 09:42, 27 February 2020 (UTC)


 * The primary cooling system used seawater for exchanging heat, so the proximity to the sea must have been a consideration in the selection of the site. The book Fukushima: The Story of a Nuclear Disaster relates how overconfidence played a role: “When construction began on the reactors in the late 1960s, engineers dismissed the likelihood that the plant location might be vulnerable. Based on the worst historical tsunami on record at the Fukushima site—resulting from a 1960 earthquake in Chile—the reactors were designed to withstand a tsunami with a maximum height of about ten feet (3.1 meters). TEPCO was so confident of this data point that the company actually lowered the height of the bluff where the plant was to be built by more than eighty feet (twenty-five meters).”  --Lambiam 09:46, 27 February 2020 (UTC)
 * The identification of the 869 tsunami - work published in 2001 - gave them ample time to reconsider the design, but ten years later nothing had been done to mitigate this risk. Mikenorton (talk) 05:48, 1 March 2020 (UTC)

also, it's on the Pacific Ocean, not the Sea of Japan, although colloquially of course, "sea of Japan" certainly includes the surrounding oceans. EllenCT (talk) 22:37, 2 March 2020 (UTC)
 * Yeah, I noticed that a couple hours after I posted it. My bad, but thanks for clarifying! 5225C (talk) 23:24, 2 March 2020 (UTC)

Natural photograph
Is there a process which spontaneously results in a picture of an object being imprinted on something, maybe in the manner of the camera obscura? Is there an instance of this having happened? Regrettably, the closest to this I can think of are shadows created by the atomic bomb in Hiroshima and Nagasaki. 93.142.73.32 (talk) 23:54, 27 February 2020 (UTC)


 * You can make an image on a plant leaf using the chemistry of photosynthesis. As described in the article, this is not a spontaneous process and only partly natural. A similar process, based on drying leaves losing their colour, can also be used to produce images, without chemical postprocessing. The opposite effect is that leaves need light to turn green, so an image should eventually also appear on a leaf from being covered by a negative for a long period of time. For this process to result in a spontaneous chlorophyll print, some flattish object should accidentally come stuck on top of a leaf, eventually leaving a yellowish mark in its shape. I bet this happens all the time, but I know of no actual instances. --Lambiam 08:35, 28 February 2020 (UTC)
 * Cool, not quite what I was going for but I'll have to try this out next fall! 93.142.73.32 (talk) 22:16, 28 February 2020 (UTC)
 * I forgot to say what inspired me was things like Archaeoacoustics, altho it looks like that was disproved later. 89.172.73.94 (talk) 00:09, 29 February 2020 (UTC)(OP)


 * Does Permineralization count? Tigraan Click here to contact me 09:28, 28 February 2020 (UTC)
 * Does it produce a 2D result? IDK much about fossils, but from what I understood they're more like natural sculptures, not photographs. That's still pretty amazing tho now that I think about it. 93.142.73.32 (talk) 22:16, 28 February 2020 (UTC)
 * The most common occurance I've seen has been when there is a thin layer of snow on the ground, and the the sun shines for a half hour before it becomes overcast again. An image of the house's shadow is left imprinted where the snow was not melted due to the house being in the way.  It can be quite a detailed and accurate image unless the sun stays out and melts it.Edison (talk) 13:30, 3 March 2020 (UTC)