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Comment by justinclift | Hacker News Reader

Hmmm, how many radar pulses need to hit a target to generate video? Sounds potentially irradating... ;)

eg: WARNING Don't attempt to image living creatures WARNING

RADAR typically uses microwaves, non-ionizing. Over this area it's bound to be a terribly, terribly small amount of exposure.

Ahhh, no worries.

Just remembering a friend recently telling me about someone who was killed at a work place. Apparently that person walked in front of the main radar array (defense related I think) while it was in operation and just dropped dead instantly. :(

This happened to a former schoolmate of mine with a pacemaker when strong EM equipment was turned on near them.

The people on site had no idea he had one and attempted to administer CPR, but they wouldn't have been able to detect his pulse, regardless.

Imagine how it looked to the people who never found out and the version of the story they might still be telling others.

At the 1933 World’s Fair in Chicago, Westinghouse demonstrated a 10-kilowatt shortwave radio transmitter that cooked steaks and potatoes between two metal plates [1]. In 1946 a Raytheon engineer named Robert Spencer "...was visiting a lab where magnetrons, the power tubes of radar sets, were being tested. Suddenly, he felt a peanut bar start to cook in his pocket. Other scientists had noticed this phenomenon, but Spencer itched to know more about it. He sent a boy out for a package of popcorn. When he held it near a magnetron, popcorn exploded all over the lab. Next morning he brought in a kettle, cut a hole in the side and put an uncooked egg (in its shell) into the pot. Then he moved a magnetron against the hole and turned on the juice. A sceptical engineer peeked over the top of the pot just in time to catch a face-full of cooked egg. The reason? The yolk cooked faster than the outside, causing the egg to burst..." [2]. This discovery led to a patent application for "the use of microwaves to heat food", a concept which was eventually realised in the "Raytheon RadaRange" series of microwave ovens [3].

[1] https://en.wikipedia.org/wiki/Microwave_oven#/media/File:Coo...

[2] https://spectrum.ieee.org/tech-history/space-age/a-brief-his...

[3] https://en.wikipedia.org/wiki/Microwave_oven#/media/File:NS_...

Given the Inverse-square law, your phone and wifi network will probably give you more radiation..

I had some bones scans (plus a couple of CTs the same day, just a bit more ionising radiation) last year. They inject you with Technician 99m and YOU become the gamma/ x-ray source. It's a little concerning when you see the detail and spread of the radiation. If it wasn't a pure Gamma source (and 6hour half-life) it would be lethal!

I forget if it was 70,000 milli or microsieverts (think it was milli? 0.5% increased risk of cancer in my lifetime). Oh, and my bladder looked like a lightbulb.

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