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R1 (Minor) Radio Blackout Impacts
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HF Radio: Weak or minor degradation of HF radio communication on sunlit side, occasional loss of radio contact.
Navigation: Low-frequency navigation signals degraded for brief intervals.
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S1 (Minor) Solar Radiation Storm Conditions Observed - 14 July 2017

S1 (Minor) Solar Radiation Storm Conditions Observed - 14 July 2017
published: Sunday, July 16, 2017 19:14 UTC

The greater than 10 MeV proton flux at geostationary orbit exceeded the S1 (Minor) solar radiation storm threshold at 14/0900 UTC. A peak flux of 22 pfu was observed at 14/2320 UTC. Flux levels decreased below S1 (Minor) levels at 15/1115 UTC.