Rocket in situ observation of equatorial plasma irregularities in the region between E and F layers over Brazil

Abstract

Abstract. A two-stage VS-30 Orion rocket was launched from the equatorial rocket launching station in Alcântara, Brazil, on 8 December 2012 soon after sunset (19:00 LT), carrying a Langmuir probe operating alternately in swept and constant bias modes. At the time of launch, ground equipment operated at equatorial stations showed rapid rise in the base of the F layer, indicating the pre-reversal enhancement of the F region vertical drift and creating ionospheric conditions favorable for the generation of plasma bubbles. Vertical profiles of electron density estimated from Langmuir probe data showed wave patterns and small-and mediumscale plasma irregularities in the valley region (100-300 km) during the rocket upleg and downleg. These irregularities resemble those detected by the very high frequency (VHF) radar installed at Jicamarca and so-called equatorial quasiperiodic echoes. We present evidence suggesting that these observations could be the first detection of this type of irregularity made by instruments onboard a rocket.

Structural characterization of the equatorial F region plasma irregularities in the multifractal context

“…Ground equipment, digisonde, near launching station, showed fast uplift of the F region base before sunset and its continuation for more than two hours, indicating possibility of pre-reversal enhancement of the vertical plasma drift (Savio et al, 2016). Further explanation of in situ experiment and data analysis is found in Savio et al (2016); Savio Odriozola et al (2017).…”

Quasiperiodic Rising Structures in the E‐F Valley Region Below the Equatorial Plasma Bubble: A Numerical Study

“…This is the reason why similarities between the measured and simulated profiles are expected. Figure presents the vertical profiles obtained through NE3 for comparison with the profiles reproduced in Figure from Savio Odriozola et al ().…”

“…Using the results from NE2 or NE3, it is possible to build n e vertical profiles at equatorial plane. These profiles can be compared with in situ n e profiles obtained using a sounding rocket (Savio Odriozola et al, ) and reproduced in Figure , lower panels. According to that work, the rocket's apogee was 428 km surpassing the F region peak.…”

“…The red lines superimposed on the RTI map highlight the similarity between the slopes associated with the effect that the ambient zonal electric field exerts on the irregularities at the base of the F region and the valley‐ E region. (bottom panels) The n e profiles obtained with a Langmuir probe on board a rocket launched from Alcântara, Brazil, in December 2012 (reproduced from Savio Odriozola et al, ). RTI = range‐time‐intensity.…”

“…Recently, Savio Odriozola et al () presented in situ measurements of upper E and VE irregularities in the electron density ( n e ) using a Lagmuir probe on board a two‐stage rocket with a trajectory close to the geomagnetic equator. The n e profile shown in this study evidenced a quasiperiodicity similar to those previously detected in radar measurements.…”