Examinando por Autor "Franzese, G."

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Periodic Bedrock Ridges at the ExoMars 2022 Landing Site: Evidence for a Changing Wind Regime
(Advancing Earth and Space Science AGU, 2021-01-12) Silvestro, S.; Pacifici, A.; Salese, F.; Vaz, D. A.; Neesemann, A.; Tirsch, D.; Popa, C. I.; Pajola, M.; Franzese, G.; Mongelluzzo, G.; Ruggeri, A. C.; Cozzolino, F.; Porto, C.; Esposito, F.; National Aeronautics and Space Administration (NASA); European Research Council (ERC); Agenzia Spaziale Italiana (ASI); Pajola, M. [0000-0002-3144-1277]; Ruggeri, A. C. [0000-0002-1556-2474]; Tirsch, D. [0000-0001-5905-5426]; Salese, F. [0000-0003-0491-0274]; Silvestro, S. [0000-0002-3196-6620]; Mongelluzzo, G. [0000-0003-1182-8252]; Franzese, G. [0000-0001-5911-3163]
Wind-formed features are abundant in Oxia Planum (Mars), the landing site of the 2022 ExoMars mission, which shows geological evidence for a past wet environment. Studies of aeolian bedforms at the landing site were focused on assessing the risk for rover trafficability, however their potential in recording climatic fluctuations has not been explored. Here we show that the landing site experienced multiple climatic changes in the Amazonian, which are recorded by an intriguing set of ridges that we interpret as Periodic Bedrock Ridges (PBRs). Clues for a PBR origin result from ridge regularity, defect terminations, and the presence of preserved megaripples detaching from the PBRs. PBR orientation differs from superimposed transverse aeolian ridges pointing toward a major change in wind regime. Our results provide constrains on PBR formation mechanisms and offer indications on paleo winds that will be crucial for understanding the landing site geology.
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Techniques to verify the sampling system and flow characteristics of the sensor MicroMED for the ExoMars 2022 Mission
(Elsevier, 2021-08-21) Cozzolino, F.; Franzese, G.; Mongelluzzo, G.; Molfese, C.; Esposito, F.; Cosimo Ruggeri, A.; Porto, C.; Silvestro, S.; Popa, C. I.; Mennella, V.; Scaccabarozzi, D.; Saggin, B.; Ortega Rico, A. M.; Arruego, I.; Santiuste, Nuria; Brienza, D.; Cortecchia, F.; de Mingo Martín, José Ramón; Instituto Nacional de Técnica Aeroespacial (INTA); Agenzia Spaziale Italiana (ASI); Istituto Nazionale di Astrofisica (INAF)
Suspended dust has a prominent role in Martian climatology. Several significant dust related phenomena can be observed at various scales, starting from global dust storms to local dust devils, which have important effects such as the increase of troposphere temperature, the modification of the wind regime and the localized motion of sand at the surface. These phenomena depend on dust grain characteristics such as the size distribution or the chemical and bulk composition. Currently, we do not have direct measurement of the dust properties; the only available information in this regard are derived from spectrometric measurements, optical depth, and albedo coming from instruments aboard satellites and in-situ. Herein, we describe the tests performed on the optical particle counter named MicroMED, designed and built to perform the first ever direct in-situ measurement of suspended dust grains in the Martian atmosphere close to the surface. MicroMED is a dust particle size analyzer which was selected to join the Dust Complex payload aboard the ESA/Roscosmos ExoMars 2022 mission. It has the capability to suck in dust that is suspended in atmosphere and to measure the sizes of single grain. The sensor sucks in the dust grains using a sampling system, guides the grains through ducts and concentrates them in an area illuminated by laser. Detecting the intensity of the light scattered by the grains during the crossing through the illuminated area, it is possible to determinate the size of grain. Here we present the innovative techniques in order to verify the performances in terms of dust suction efficiency of the MicroMED Flight Model, using a prototype called MM1.