Rocket observation of sporadic-E layers and electron density irregularities over midlatitude Original Research Article

Irregularities in electron density related to a nighttime sporadic-E (Es) layer were measured by a fixed-bias Langmuir probe onboard the sounding rocket S-310-25, launched at 23:00:00 JST on August 26, 1996 during the SEEK observation campaign. The most interesting finding was the existence of multiple-Es layers which were separated by 10 – 12 km within a wide altitude range of 90 – 130 km. Meter-scale irregularities generated in association with the multiple-Es layers were found to exist in a similar altitude range as quasi-periodic (QP) echoes, which were detected with frequency agile radar (FAR) operating at 24.5 MHz around the time of the rocket flight.