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Человек склеил из осколков параболическое зеркало и прожигает солнцем бетонные плиты:


Двое других запустили видеокамеру в космос на воздушном шаре и проверили шарообразность земли:

Date: 2011-02-04 06:35 am (UTC)
From: [identity profile] dmpogo.livejournal.com
I was wondering how did he get a parabolic shape - but he just glued the mirrors to satellite dish.

Date: 2011-02-04 09:25 am (UTC)
From: [identity profile] averros.livejournal.com
I wonder why he spent all that time gluing the mirrors on instead of simply polishing (and possibly silvering) the dish. Could've gotten smaller spot:)

Date: 2011-02-04 03:17 pm (UTC)
From: [identity profile] dmpogo.livejournal.com
Well, satellite dishes are designed to receive at something like 10cm wavelength. Which means their surfaces can be pretty rough, +-1 mm or even few. It is a some way to go to have them polished to optical wavelengths. There is a remark that the dish was relatively rough.

Given it did not take him that long to glue the pieces on, just a day or so, it maybe was an easiest way that also requires no tools