The Organism/Organic Exposure to Orbital Stresses (O/OREOS) satellite: radiation exposure in low-earth orbit and supporting laboratory studies of iron tetraphenylporphyrin chloride

Chemical, Thermal, and Radiation Resistance of an Iron Porphyrin: A Model Study of Biosignature Stability

Metal complexes of porphyrins and porphyrin-type compounds are ubiquitous in all three domains of life, with hemes and chlorophylls being the best-known examples. Their diagenetic transformation products are found as geoporphyrins, in which the characteristic porphyrin core structure is retained and which can be up to 1.1 billion years old. Because of this, and their relative ease of detection, metalloporphyrins appear attractive as chemical biosignatures in the search for extraterrestrial life. In this study, we investigated the stability of solid chlorido(2,3,7,8,12,13,17,18-octaethylporphyrinato)iron(III) [FeCl(oep)], which served as a model for heme-like molecules and iron geoporphyrins. [FeCl(oep)] was exposed to a variety of astrobiologically relevant extreme conditions, namely: aqueous acids and bases, oxidants, heat, and radiation. Key results are: (1) the [Fe(oep)]⁺ core is stable over the pH range 0.0-13.5 even at 80°C; (2) the oxidizing power follows the order ClO^- > H₂O₂ > ClO₃^- > HNO₃ > ClO₄^-; (3) in an inert atmosphere, the iron porphyrin is thermally stable to near 250°C; (4) at high temperatures, carbon dioxide gas is not inert but acts as an oxidant, forming carbon monoxide; (5) a decomposition layer is formed on ultraviolet irradiation and protects the [FeCl(oep)] underneath; (6) an NaCl/NaHCO₃ salt mixture has a protective effect against X-rays; and (7) no such effect is observed when [FeCl(oep)] is exposed to iron ion particle radiation. The relevance to potential iron porphyrin biosignatures on Mars, Europa, and Enceladus is discussed.

Role of microfluidics in accelerating new space missions

Numerous revolutionary space missions have been initiated and planned for the following decades, including plans for novel spacecraft, exploration of the deep universe, and long duration manned space trips. Compared with space missions conducted over the past 50 years, current missions have features of spacecraft miniaturization, a faster task cycle, farther destinations, braver goals, and higher levels of precision. Tasks are becoming technically more complex and challenging, but also more accessible via commercial space activities. Remarkably, microfluidics has proven impactful in newly conceived space missions. In this review, we focus on recent advances in space microfluidic technologies and their impact on the state-of-the-art space missions. We discuss how micro-sized fluid and microfluidic instruments behave in space conditions, based on hydrodynamic theories. We draw on analyses outlining the reasons why microfluidic components and operations have become crucial in recent missions by categorically investigating a series of successful space missions integrated with microfluidic technologies. We present a comprehensive technical analysis on the recently developed in-space microfluidic applications such as the lab-on-a-CubeSat, healthcare for manned space missions, evaluation and reconstruction of the environment on celestial bodies, in-space manufacturing of microfluidic devices, and development of fluid-based micro-thrusters. The discussions in this review provide insights on microfluidic technologies that hold considerable promise for the upcoming space missions, and also outline how in-space conditions present a new perspective to the microfluidics field.

Designing bifuncitonal molecular devices with a metalloporphyrin dimer

Many organic molecules have unique magnetic properties and can potentially serve as excellent molecular spin devices, which is worth exploring deeply. Here, the spin transport properties of Mn, Fe, Co and Cu porphyrin dimer devices are investigated based on the first principles method. The spin filtering efficiencies of these molecular devices are maintained at 100% within certain applied voltage ranges and magnetoresistance ratios are higher than 10⁸% which increase as the voltage increases. To explain the excellent spin-filtering and giant magnetoresistance effects, analysis of spin electron densities and transmission spectra indicates that magnetic properties are mainly contributed by the metal atoms and their neighbouring N atoms. From the transmission pathway studies, spin electrons come mainly through the π-conjugated structure of the metal porphyrin ring. Interestingly, in the Cu porphyrin dimer device, magnetic moments of the Cu-N structure in the Cu porphyrin dimer device show spin behaviors different from those of Mn, Fe and Co porphyrin dimer devices.

AstRoMap European Astrobiology Roadmap

The European AstRoMap project (supported by the European Commission Seventh Framework Programme) surveyed the state of the art of astrobiology in Europe and beyond and produced the first European roadmap for astrobiology research. In the context of this roadmap, astrobiology is understood as the study of the origin, evolution, and distribution of life in the context of cosmic evolution; this includes habitability in the Solar System and beyond. The AstRoMap Roadmap identifies five research topics, specifies several key scientific objectives for each topic, and suggests ways to achieve all the objectives. The five AstRoMap Research Topics are • Research Topic 1: Origin and Evolution of Planetary Systems • Research Topic 2: Origins of Organic Compounds in Space • Research Topic 3: Rock-Water-Carbon Interactions, Organic Synthesis on Earth, and Steps to Life • Research Topic 4: Life and Habitability • Research Topic 5: Biosignatures as Facilitating Life Detection It is strongly recommended that steps be taken towards the definition and implementation of a European Astrobiology Platform (or Institute) to streamline and optimize the scientific return by using a coordinated infrastructure and funding system.