Wikipedia:Reference desk/Archives/Science/2014 June 28

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June 28

Rescue dogs

What are some of the mission-specific commands given to SAR dogs (e.g. to commence a specific type of search, to return to handler, to leave a dangerous area, etc.)? Thanks in advance! 24.5.122.13 (talk) 01:04, 28 June 2014 (UTC)

Have you read SAR dog#Training ? 84.209.89.214 (talk) 01:18, 28 June 2014 (UTC)

Yes, but the only actual commands it mentions is "Go find!" and "Show me!" -- what other commands (if any) are there? (I don't mean generic commands like "Heel!", "Sit-stay!", etc. -- I mean commands specific to the search-rescue mission.) 24.5.122.13 (talk) 01:48, 28 June 2014 (UTC)

How certain are you that the dogs get more commands than that? Dogs are marvelously intelligent creatures, especially next to things like trees and congressmen, but I doubt search and rescue dogs are doing anything more complex than playing the "find the smell and get a treat" game. "Go find" and "show me" are sufficient commands for what they need to do. As with any tool, it's up to the humans to do the real work and use the dogs properly. --Jayron32 03:46, 28 June 2014 (UTC)

[1] [2] [3] [4] [5] Snow talk 04:28, 28 June 2014 (UTC)

Thank you for all this info, SnowRise! This is lots of great research info, with the Koven link being particularly helpful. (Now I know how TJ, the ski patrol leader, will communicate with his rescue dog Detrick while they're digging up victims from that super-avalanche.) 24.5.122.13 (talk) 08:01, 28 June 2014 (UTC)

De rien. Stay safe. Snow talk 11:39, 28 June 2014 (UTC)

/* Rescue dogs */ Rescue dogs have many commands that they are capable of learning in training. SAR dogs are taught obedience and directional commands because eventually the dog will be let off their leash and trusted that they will be successful taking commands. In the phase I training for a search dog, they teach the dogs commands like "search" and "find" when given a certain scent to find that is set in place by their trainer. With this training, the dogs learn to bark on command when the find an air scent to alert their owner. The SAR dogs are used for police work, protection, security, etc. They know they are completely trained when they know all the commands and do not bite, unless instructed to. All of this information can be found at the following sites: https://www.avma.org/News/Journals/Collections/Documents/javma_225_6_854.pdf , http://www.nasar.org/page/49/Canine-Fact-Sheet , http://www.vsar.org/SARdog.html . Sbrockhoff (talk) 20:01, 3 July 2014 (UTC)

What's going on in Darwin?

Checking up on something at WP:ANI led me to http://www.ntnews.com.au, where to my surprise I saw that today's temperatures for Darwin are 18°C and -31°C. What's going on? How do they have such a horribly cold day, so far north in the tropics? Nyttend (talk) 03:53, 28 June 2014 (UTC)

Sounds like a mistake. I would guess that's supposed to be a low of +18°C and high of +31°C. StuRat (talk) 04:06, 28 June 2014 (UTC)

Yes, it looks like a typo. weather.com says that the observed low and high in Darwin, AU on June 27 were +19°C and +29°C, respectively.[6] Red Act (talk) 04:17, 28 June 2014 (UTC)

The lowest temperature ever recorded in Australia was nowhere near that low. Something like -17°C, in the Snowy Mountains (a long way from Darwin), in the 1990s. -- Jack of Oz ^{[pleasantries]} 06:44, 28 June 2014 (UTC)

Okay, all of this makes a lot more sense than I was imagining; thanks for the confirmation that I'm not going crazy and that the world isn't about to go into deep freeze. Nyttend (talk) 11:27, 28 June 2014 (UTC)

Some news services have a mathematically unsound way of displaying minima and maxima temperatures. If the minimum was 18°C and the maximum was 31°C they would set out to display it as 18 to 31 but they would use a hyphen instead of the word "to". Consequently it would appear as 18-31. This could be mistaken as plus 18 to minus 31. What is intended is a temperature range from a low of 18°C through to a maximum of 31°C. Dolphin (t) 12:47, 1 July 2014 (UTC)

why so few craters?

plenty of craters

Why does this video] from LRO show so few craters? Were the pictures taken when there were no shadows? Bubba73 ^{You talkin' to me?} 05:58, 28 June 2014 (UTC)

Are we watching the same video? I see about as many craters as I would expect given the resolution of the video and the size of the moon in that video. Which crater do you find that is missing? --Jayron32 06:03, 28 June 2014 (UTC)

Few? There seem to be plenty of craters to me - but yes, clearly the image is a composite made of images with the orbiter directly over the sunlit side of the Moon, meaning that shadows are minimised. AndyTheGrump (talk) 06:07, 28 June 2014 (UTC)

Compare that to the photo I just added. Bubba73 ^{You talkin' to me?} 07:01, 28 June 2014 (UTC)

The near side of the moon has many lunar maria ("seas"), very large craters that have been filled with relatively dark, smooth lava. The far side of the moon has only a few small maria. There are craters everywhere, but most of them are smaller and much lighter in color than the maria. From Earth, we only see the near side, so we see a lot of the surface covered in dark maria. Perhaps you're just noticing that the rest of the moon looks very lighter and much different. --Amble (talk) 07:17, 28 June 2014 (UTC)

No, what I'm actually asking about is that plenty of craters are visible in that photo, but I don't see many in the video. It must be because the shadows make them visible. Bubba73 ^{You talkin' to me?} 11:39, 28 June 2014 (UTC)

Indeed. Our fake libration animation gives the same erroneous impression. To the beginner, it might seem that the full moon is the best time to check out our nearest neighbour, but in fact that's a pretty poor time to look at it because many of the interesting features are wiped out by brightness and lack of contrasting shadows; you see a lot more when the sun's rays strike the moon from an angle rather than directly overhead. Matt Deres (talk) 12:11, 28 June 2014 (UTC)

It must be more deliberate than that. The Lunar Reconnaissance Orbiter doesn't just sit somewhere near the sun taking pictures; it's in orbit around the Moon and would tend to pick up many shadows. It generated highly detailed topographic maps. And of course the poles of the Moon aren't without shadow. So this particular video must have intentionally extracted just the albedo from its data by some means. Wnt (talk) 13:12, 28 June 2014 (UTC)

Bubba: OK, I thought you might have been looking at the Maria since they are the most familiar kinds of lunar crater visible from Earth. This page [7] from Arizona State University has some information about how the image was made. Essentially, they made images in strips when the sun was overhead, corrected the off-center parts of each strip, and stitched them together to make a single image with no shadows. As you say, that shows you just the albedo with none of the lighting cues that usually make craters more visible to the eye. --Amble (talk) 01:03, 29 June 2014 (UTC)

It looks as though the craters have all slumped, or been weathered, flat. Reminds me of Callisto. —Tamfang (talk) 03:31, 29 June 2014 (UTC)

Tesseract house

Would it be possible to build a house like this at all, even if it was with sufficiently advanced technology? Feitlebaum (talk) 23:38, 28 June 2014 (UTC)

There's absolutely zero evidence of a macroscopic fourth dimension of space, so unless your sufficiently advanced technology involves relocating to a radically different universe, no. AlexTiefling (talk) 23:50, 28 June 2014 (UTC)

Heinlein's story tells of the building of a house in the shape of the 3-D projection of an unrealizable 4-D tesseract, and this is possible. However after an earthquake it would not behave in the impossible way described in the story. Linking to Clarke's three "laws of prediction" (scarequotes deliberate) suggests a love of science fiction but does not affect the answer given. 84.209.89.214 (talk) 01:44, 29 June 2014 (UTC)

There was a study published about 2000 that with a few weeks intensive use of 4D virtual reality goggle you could learn to navigate and comprehend $D shapes and spaces as intuitively as 3D. μηδείς (talk) 18:10, 29 June 2014 (UTC)