Solid carbon is deposited on the surfaces of an inductively coupled plasma torch operating with a Titan like atmosphere plasma gas. The frame of the initial research is the study of the radiative properties of plasma encountered around a spacecraft during its hypersonic entry in upper layers of planetary atmosphere. Deposition of carbon is observed not only on the quartz tube outside the inductor but also on the ceramic protection of the torch injector. Carbon exhibits two types of morphology more or less dense and it is analyzed by various analytic devices as MEB, SEM, TEM, EDS and Raman spectroscopy. The gathered carbon powder shows the presence of nanostructured particles. 1. Introduction The atmospheric entry of a spacecraft is a critical phase for the success of a planet exploration, and an efficient thermal protection system (TPS) is required to protect the probe against the energy surface flux. For a high velocity entry ( 11？ ) in the upper layers of the atmosphere of the planet, the radiative flux of energy issued from the plasma created in the shock layer is predominant compared to convective flux (up to ten times more). New materials are currently studied to increase the protection without negative effect on the mass of the probe as phenolic materials [1, 2]. As a consequence, the study of radiative properties of such plasmas (formed with Earth, Mars, or Titan atmospheres) is required to optimize the size (thickness, mass) of the TPS (front shield and back shield). In order to simulate the radiative properties of the encountered plasmas during an atmospheric entry, various experimental devices are used as shock tubes, arc jets, microwave plasmas, and inductively or capacitively coupled plasma torches [3]. From these devices, various entry configurations, in terms of pressure and velocity by shock tubes, nonequilibrium of ionization, and radiative processes by the other facilities, can be studied. The study of Titan, Saturn’s largest moon, is of great scientific interest due to some similarities with the Earth discovered by the NASA’s Cassini spacecraft (2004) as seasonal and daily changes, clouds, winds, and surface aspects [4] but with a lower surface temperature ( 100？K). Its thick atmosphere is mainly composed of nitrogen and methane with traces of ammonia, argon and carbon dioxide, propane, and ethane and could host preliminary elements of microbiological life. Thus, to prepare new missions of Titan exploration, the radiative properties of a Titan-like atmosphere plasma (98% -2% ) have been investigated to deepen the knowledge of the
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