Abstract
The Scintillation Prediction Observation Research Task (SPORT) international collaborative mission will advance our understanding of the nature and evolution of ionospheric structures around sunset to improve predictions of disturbances that affect radio propagation and telecommunication signals. Structure in the charged particle number density in the equatorial ionosphere can have a profound impact on the fidelity of HF, VHF and UHF radio signals that are used for ground-to-ground and space-to-ground communication and navigation. The degree to which such systems can be compromised depends in large part on the spatial distribution of the structured regions in the ionosphere and the background plasma density in which they are embedded. Plasma structures originate in the bottom side of the ionospheric layer known as the F region where they may be resident most of the time during the nighttime. However, if conditions allow the structured regions to penetrate through the bottom side F region and into and above the peak of the layer, then the plasma structures may be of sufficient magnitude to create significant perturbations in both the propagation path of radio signals as well as changes in the signal phase and amplitude, known as scintillation. Discovering the conditions under which the most detrimental effects on radio wave propagation exist remains a challenge to both our observational capability and our physical understanding. The background ionospheric conditions are conveniently described by latitudinal profiles of the plasma density at nearly constant altitude, which describe the effects of ExB drifts and neutral winds, while the appearance and growth of plasma structure requires committed observations from the ground from at least one fixed longitude. These goals will be accomplished by a unique combination of satellite observations from a nearly circular middle inclination orbit and the extensive operation of ground based observations from South America near the magnetic equator. Our proposed mission will produce a coordinated set of measurements of the F-peak height and density as well as the vertical plasma motions and plasma density in the local time region from 1500 to 2400 over a magnetic latitude range from +/-30°. The advent of reliable derivation of F-peak density and height from radio occultation receivers allows these parameters, which are sensitive functions of the vertical plasma motion, to be specified from an orbiting satellite in a large range in local time and longitude around the equator. Coupled with in-situ measurements of the plasma drifts and plasma density, it is possible to tie together the local and regional behaviors described by these data sources using well-established physical links as well as powerful new machine learning techniques. With SPORT we propose to undertake such a study utilizing a simple cube-sat payload consisting of the following instruments: Langmuir impedance probe, drift meter, radio occultation sensor and a magnetometer. The mission will feature a strong collaboration with the National Aeronautics and Space Administration (NASA), Utah State University (USU), University of Alabama in Huntsville (UAH) and the National Institute for Space Research (INPE). The proposed instruments will be hosted on an ITA U-class (6U) platform (based on ITASAT) launched from the ISS. This proposal covers the 6U platform and its team, the Physics Laboratory at ITA, and a supporting role for the contributed components from the American contingent of NASA USU, UAH and INPE that includes I&T, mission operations, and data collection/reduction/dissemination. Additionally, use of an extensive ground based ionospheric observational network operated by INPE at different locations in Brazil will be available. (AU)
| Articles published in Agência FAPESP Newsletter about the research grant: |
| More itemsLess items |
| TITULO |
| Articles published in other media outlets ( ): |
| More itemsLess items |
| VEICULO: TITULO (DATA) |
| VEICULO: TITULO (DATA) |