Dr Antonin Knizek

Abstract:

The end of the late heavy bombardment era coincides with the emergence of life on the Earth 4 billion years ago. This coincidence suggests that the impacts of extraterrestrial bodies might have contributed to the formation of the first molecules involved in early living structures. We have simulated a high-energy synthesis of nucleic acid bases from formamide in the impact of an extraterrestrial body. The high-power laser system PALS was employed in simulation of impact plasma by inducing a laser dielectric breakdown in formamide. In hot and dense plasma, formamide decomposed producing reactive radicals. The radicals reacted with formamide and nucleic acid bases were produced. Formamide was pretreated with laser plasma in the presence of catalysts. The products were analyzed by FTIR spectrometry and GC-MS. Time-resolved emission spectra of formamide discharge plasma were measured. Kinetic models and formation pathways for nucleic acid bases were calculated. The results show that the nucleic acid bases can be synthesized in impact plasma involving CN and NH radicals and formamide.

Abstract:

Ariel, the Atmospheric Remote-sensing Infrared Exoplanet Large-survey, was adopted as the fourth medium-class mission in ESA's Cosmic Vision programme to be launched in 2029. During its 4-year mission, Ariel will study what exoplanets are made of, how they formed and how they evolve, by surveying a diverse sample of about 1000 extrasolar planets, simultaneously in visible and infrared wavelengths. It is the first mission dedicated to measuring the chemical composition and thermal structures of hundreds of transiting exoplanets, enabling planetary science far beyond the boundaries of the Solar System. The payload consists of an off-axis Cassegrain telescope (primary mirror 1100 mm x 730 mm ellipse) and two separate instruments (FGS and AIRS) covering simultaneously 0.5-7.8 micron spectral range. The satellite is best placed into an L2 orbit to maximise the thermal stability and the field of regard. The payload module is passively cooled via a series of V-Groove radiators; the detectors for the AIRS are the only items that require active cooling via an active Ne JT cooler. The Ariel payload is developed by a consortium of more than 50 institutes from 16 ESA countries, which include the UK, France, Italy, Belgium, Poland, Spain, Austria, Denmark, Ireland, Portugal, Czech Republic, Hungary, the Netherlands, Sweden, Norway, Estonia, and a NASA contribution.