4 ms·
Cosmic rays are more common than you think. Google's early infrastructure was impacted by a supernova (because their nodes were so cheap). But something like N
by shemnon42 4y ago
Cosmic rays are more common than you think. Google's early infrastructure was impacted by a supernova (because their nodes were so cheap). But something like NOTAM can handle these single bit flips without a problem.
https://www.newyorker.com/magazine/2018/12/10/the-friendship-that-made-google-huge https://www.newyorker.com/magazine/2018/12/10/the-friendship...
File this under "early Google's infrastructure was a low grade cosmic ray detector."
- defrost 4y agoYou can expect 250 or so cosmic ray events per second in a 42 litre sodium iodide crystal pack at 100m above sea level. Source: 10 years airbourne geophysics, radiometric calibrations. Addendum: In-flight upset 154 km west of Learmonth, WA 7 October 2008 VH-QPA Airbus A330-303 [1] was a probable (but uncertain) example of cosmic ray events causing multiple spikes in one of three air data inertial reference units (ADIRUs) that also went on to cause a failure mode of the "best of three" reporting system leading to a pitch down in which [2] > 110 of the 303 passengers and nine of the 12 crew members were injured; 12 of the occupants were seriously injured and another 39 received hospital medical treatment. HOWEVER .. despite 250 events per second in a 42 litre volume, it took 128 million hours of unit operation to see a failure mode. It's a lot of billiard balls going through a lot of space and a high bar for "something bad" ( just the right bit flip ) to happen. [1] https://www.atsb.gov.au/sites/default/files/media/3532398/ao2008070.pdf https://www.atsb.gov.au/sites/default/files/media/3532398/ao... [2] https://www.atsb.gov.au/publications/investigation_reports/2008/aair/ao-2008-070 https://www.atsb.gov.au/publications/investigation_reports/2... ( Final Report TAB )