Event DetailsEvent Dates: Friday, October 27, 2017 - 12:00pmSeminar Location: JILA 10th Floor - Foothills RoomSpeaker Name(s): Delores J. KnippSpeaker Affiliation(s): Colorado Center for Astrodynamics Research, CU Boulder Seminar Type/SubjectScientific Seminar Type: Astrophysics Lunch SeminarEvent Details & Abstract: Although listed as one of the most significant solar storms of the last 80 years, the space weather storm of late May 1967 has been largely forgotten. I will explain how the May 1967 storm was nearly one with ultimate societal impact, were it not for the nascent efforts of CU-educated Air Force officers in monitoring and forecasting the extraordinary solar conditions and geospace responses on 23-27 May 1967. On 23 May an initial “great” solar radio burst, which caused radio interference at frequencies between 0.01-9.0 GHz, was accompanied by near-simultaneous disruptions of dayside radio communication by intense fluxes of ionizing solar X-rays. Aspects of military control and communication were immediately challenged. Shortly thereafter a solar energetic particle event interfered with high-frequency communication in the polar cap. Subsequently, record-setting geomagnetic and ionospheric storms compounded the disruptions. I detail three aspects of the storm: The great radio burst; the solar energetic particles; and the surprising effects on upper atmospheric temperature. As noted in Knipp et al.  this was one of the “Great Storms” of the 20th century, despite the lack of reported geomagnetically-induced currents. Radio disruptions such as these warrant the attention of today’s radio-reliant, cellular-phone and satellite-navigation enabled world.