The Calar Alto Observatory, located at 2168m height above the sea level in continental Europe, ho... more The Calar Alto Observatory, located at 2168m height above the sea level in continental Europe, holds a signi?cant number of astronomical telescopes and experiments, covering a large range of the electromagnetic domain, from gamma-ray to near-infrared. It is a very well characterized site, with excellent logistics. Its main telescopes includes a large suite of instruments. At the present time, new instruments, namely CAFE, PANIC and Carmenes, are under development. We are also planning a new operational scheme in order to optimize the observatory resources.
Recent geological evidence strongly suggests that Europa may currently possess a global subsurfac... more Recent geological evidence strongly suggests that Europa may currently possess a global subsurface water ocean. Since liquid water is a fundamental requirement for life as we know it, there is great speculation on the possibility of life in Europa. For such organisms to survive, there must be an energy source available for metabolism, growth and reproduction. On Earth this energy is principally derived from sunlight through photosynthesis. Due to the expected large ice crust thickness (10 to 100 km) of the satellite, this energy source is unlikely to support a biosphere. Hydrothermal vents have been suggested as a potential environment for chemotrophs. However, for such organisms to obtain energy they depend on oxidants dissolved and transported from the oxygenic Earth's atmosphere to the deep ocean. Without a supply of oxidants from Europa's crust, methanogenesis associated to hydrothermal vents may potentially drive a biosphere in Europa's ocean. Here we explore this possibility experimentally by simulating a hydrothermal vent relevant to Europa and analyzing the resulting gas products by gas chromatography coupled to Fourier transform infrared and mass spectrometries. The chemical composition of the hydrothermal vent gases was derived from a thermochemical model assuming that Europa had a cometary (solar, less H) abundance at a high temperature characteristic of a vent. Specifically the following gas mixture was used: 45% CO2 , 45% CH4 and 10 % N2 . A 500 ml stainless steel reactor was filled with 200 ml triply distilled water and the gas mixture at 1 bar at 25 °C . In some experiments 3 g of pyrite were added into the reaction vessel. The system was heated for 24 hrs at 350 °C . At the completion of the experiment, the reaction was quenched to 25 °C and the gas mixture gas analyzed by GC-FTIR-MS techniques. In the absence of pyrite, methane is oxidized to carbon dioxide with the possible production of hydrogen. In contrast in the presence of pyrite, methane is converted into a suite of hydrocarbons from C2 to C7 containing all possible isomers. The production of these compounds was found at temperatures as low as 150 °C . In order to get a better understanding of the chemical mechanism involved in the synthesis of hydrocarbons and explore the effect on the initial oxidation state of the carbon used, we performed new experiments in which the oxidation state of carbon was varied from 100% methane to 100% carbon dioxide. In all cases, a suite of complex hydrocarbons were formed in the hydrothermal simulations. Therefore, our results strongly support two possible forms of methanogenesis in Europa driven by : 1) Reduction of CO2 to CH4 using H2 ; and 2) Cleavage of hydrocarbons back to CH 4 .
The Calar Alto Observatory, located at 2168m height above the sea level in continental Europe, ho... more The Calar Alto Observatory, located at 2168m height above the sea level in continental Europe, holds a signi?cant number of astronomical telescopes and experiments, covering a large range of the electromagnetic domain, from gamma-ray to near-infrared. It is a very well characterized site, with excellent logistics. Its main telescopes includes a large suite of instruments. At the present time, new instruments, namely CAFE, PANIC and Carmenes, are under development. We are also planning a new operational scheme in order to optimize the observatory resources.
Recent geological evidence strongly suggests that Europa may currently possess a global subsurfac... more Recent geological evidence strongly suggests that Europa may currently possess a global subsurface water ocean. Since liquid water is a fundamental requirement for life as we know it, there is great speculation on the possibility of life in Europa. For such organisms to survive, there must be an energy source available for metabolism, growth and reproduction. On Earth this energy is principally derived from sunlight through photosynthesis. Due to the expected large ice crust thickness (10 to 100 km) of the satellite, this energy source is unlikely to support a biosphere. Hydrothermal vents have been suggested as a potential environment for chemotrophs. However, for such organisms to obtain energy they depend on oxidants dissolved and transported from the oxygenic Earth's atmosphere to the deep ocean. Without a supply of oxidants from Europa's crust, methanogenesis associated to hydrothermal vents may potentially drive a biosphere in Europa's ocean. Here we explore this possibility experimentally by simulating a hydrothermal vent relevant to Europa and analyzing the resulting gas products by gas chromatography coupled to Fourier transform infrared and mass spectrometries. The chemical composition of the hydrothermal vent gases was derived from a thermochemical model assuming that Europa had a cometary (solar, less H) abundance at a high temperature characteristic of a vent. Specifically the following gas mixture was used: 45% CO2 , 45% CH4 and 10 % N2 . A 500 ml stainless steel reactor was filled with 200 ml triply distilled water and the gas mixture at 1 bar at 25 °C . In some experiments 3 g of pyrite were added into the reaction vessel. The system was heated for 24 hrs at 350 °C . At the completion of the experiment, the reaction was quenched to 25 °C and the gas mixture gas analyzed by GC-FTIR-MS techniques. In the absence of pyrite, methane is oxidized to carbon dioxide with the possible production of hydrogen. In contrast in the presence of pyrite, methane is converted into a suite of hydrocarbons from C2 to C7 containing all possible isomers. The production of these compounds was found at temperatures as low as 150 °C . In order to get a better understanding of the chemical mechanism involved in the synthesis of hydrocarbons and explore the effect on the initial oxidation state of the carbon used, we performed new experiments in which the oxidation state of carbon was varied from 100% methane to 100% carbon dioxide. In all cases, a suite of complex hydrocarbons were formed in the hydrothermal simulations. Therefore, our results strongly support two possible forms of methanogenesis in Europa driven by : 1) Reduction of CO2 to CH4 using H2 ; and 2) Cleavage of hydrocarbons back to CH 4 .
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Papers by Lorena Montoya