The development of algorithms for agile science and autonomous exploration has been pursued in contexts ranging from spacecraft to planetary rovers to unmanned aerial vehicles to autonomous underwater vehicles. In situations where time, mission resources and communications are limited and the future state of the operating environment is unknown, the capability of a vehicle to dynamically respond to changing circumstances without human guidance can substantially improve science return. Such capabilities are difficult to achieve in practice, however, because they require intelligent reasoning to utilize limited resources in an inherently uncertain environment. Here we discuss the development, characterization and field performance of two algorithms for autonomously collecting water samples on VALKYRIE (Very deep Autonomous Laser-powered Kilowatt-class Yo-yoing Robotic Ice Explorer), a glacier-penetrating cryobot deployed to the Matanuska Glacier, Alaska (Mission Control location: 61°42′09.3″N 147°37′23.2″W). We show performance on par with human performance across a wide range of mission morphologies using simulated mission data, and demonstrate the effectiveness of the algorithms at autonomously collecting samples with high relative cell concentration during field operation. The development of such algorithms will help enable autonomous science operations in environments where constant real-time human supervision is impractical, such as penetration of ice sheets on Earth and high-priority planetary science targets like Europa.

Astrobiology is usually defined as the study of the origin, evolution, distribution and future of life in the Universe. As such it is inherently interdisciplinary and cannot help but engender a worldview infused by cosmic and evolutionary perspectives. Both these attributes of the study of astrobiology are, and will increasingly prove to be, beneficial to society regardless of whether extraterrestrial life is discovered or not.

Astrobiology seeks to understand the limits of life and to determine the physiology of organisms in order to better assess the habitability of other worlds. To successfully achieve these goals we require microorganisms from environments on Earth that approximate to extraterrestrial environments in terms of physical and/or chemical conditions. The most challenging of these environments with respect to sample collection, isolation and cultivation of microorganisms are anoxic environments. In this paper, an approach to this challenge was implemented within the European Union's MASE (Mars Analogues for Space Exploration) project. In this review paper, we aim to provide a set of methods for future field work and sampling campaigns. A number of anoxic environment based on characteristics that make them analogous to past and present locations on Mars were selected. They included anoxic sulphur-rich springs (Germany), the salt-rich Boulby Mine (UK), a lake in a basaltic context (Iceland), acidic sediments in the Rio Tinto (Spain), glacier samples (Austria) and permafrost samples (Russia and Canada). Samples were collected under strict anoxic conditions to be used for cultivation and genomic community analysis. Using the samples, a culturing approach was implemented to enrich anaerobic organisms using a defined medium that would allow for organisms to be grown under identical conditions in future physiological comparisons. Anaerobic microorganisms were isolated and deposited with the DSMZ (Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH) culture collection to make them available to other scientists. In MASE, the selected organisms are studied with respect to survival and growth under Mars relevant stresses. They are artificially fossilized and the resulting biosignatures studied and used to investigate the efficacy of life detection instrumentation for planetary missions. Some of the organisms belong to genera with medical and environmental importance such as Yersinia spp., illustrating how astrobiology field research can be used to increase the availability of microbial isolates for applied terrestrial purposes.

We discuss how visions for the futures of humanity in space and SETI are intertwined, and are shaped by prior work in the fields and by science fiction. This appears in the language used in the fields, and in the sometimes implicit assumptions made in discussions of them. We give examples from articulations of the so-called Fermi Paradox, discussions of the settlement of the Solar System (in the near future) and the Galaxy (in the far future), and METI. We argue that science fiction, especially the campy variety, is a significant contributor to the ‘giggle factor’ that hinders serious discussion and funding for SETI and Solar System settlement projects. We argue that humanity's long-term future in space will be shaped by our short-term visions for who goes there and how. Because of the way they entered the fields, we recommend avoiding the term ‘colony’ and its cognates when discussing the settlement of space, as well as other terms with similar pedigrees. We offer examples of science fiction and other writing that broaden and challenge our visions of human futures in space and SETI. In an appendix, we use an analogy with the well-funded and relatively uncontroversial searches for the dark matter particle to argue that SETI's lack of funding in the national science portfolio is primarily a problem of perception, not inherent merit.

Recent work in developing self-replicating machines has approached the problem as an engineering problem, using engineering materials and methods to implement an engineering analogue of a hitherto uniquely biological function. The question is – can anything be learned that might be relevant to an astrobiological context in which the problem is to determine the general form of biology independent of the Earth. Compared with other non-terrestrial biology disciplines, engineered life is more demanding. Engineering a self-replicating machine tackles real environments unlike artificial life which avoids the problem of physical instantiation altogether by examining software models. Engineering a self-replicating machine is also more demanding than synthetic biology as no library of functional components exists. Everything must be constructed de novo. Biological systems already have the capacity to self-replicate but no engineered machine has yet been constructed with the same ability – this is our primary goal. On the basis of the von Neumann analysis of self-replication, self-replication is a by-product of universal construction capability – a universal constructor is a machine that can construct anything (in a functional sense) given the appropriate instructions (DNA/RNA), energy (ATP) and materials (food). In the biological cell, the universal construction mechanism is the ribosome. The ribosome is a biological assembly line for constructing proteins while DNA constitutes a design specification. For a photoautotroph, the energy source is ambient and the food is inorganic. We submit that engineering a self-replicating machine opens up new areas of astrobiology to be explored in the limits of life.

This work is inspired by the discovery of a new class of dynamical system described by ordinary differential equations coupled with their Liouville equation. These systems called self-controlled since the role of actuators is played by the probability produced by the Liouville equation. Following the Madelung equation that belongs to this class, non-Newtonian properties such as randomness, entanglement and probability interference typical for quantum systems have been described. Special attention was paid to the capability to violate the second law of thermodynamics, which makes these systems neither Newtonian, nor quantum. It has been shown that self-controlled dynamical systems can be linked to mathematical models of living systems. The discovery of isolated dynamical systems that can decrease entropy in violation of the second law of thermodynamics, and resemblances of these systems to livings suggests that ‘Life’ can slow down the ‘heat death’ of the Universe and that can be associated with the Purpose of Life.

Creating a unified model of life in the universe – history, extent and future – requires both scientific and humanities research. One way that humanities can contribute is by investigating the relationship between philosophical commitments and data. Making those commitments transparent allows scientists to use the data more fully. Insights in four areas – history, ethics, religion and probability – demonstrate the value of careful, astrobiology-specific humanities research for improving how we talk and think about astrobiology as a whole. First, astrobiology has a long and influential history. Second, astrobiology does not decentre humanity, either physically or ethically. Third, astrobiology is broadly compatible with major world religions. Finally, claims about the probability of life arising or existing elsewhere rest heavily on philosophical priors. In all four cases, identifying philosophical commitments clarifies the ways in which data can tell us about life.

Many researchers are investigating the extreme resilience of bacterial endospores against chemical and physical inactivating agents. The presence of vegetative cells in spore suspensions can result in overly optimistic assessment of inactivating agents; therefore, various spore purification methods have been applied to separate spores from vegetative cells prior to testing. The present study was undertaken to evaluate the effect of two widely used spore purification methodologies on spore integrity and susceptibility to ultraviolet-A (UVA) radiation and free radicals generated from photocatalysts. Bacillus subtilis and Bacillus cereus spores were purified by procedures that involved heat shock alone or chemical washes, lysozyme treatment and heat shock (CLH). The purified spores were exposed to UVA radiation or free radicals generated by photocatalyst and susceptibility were evaluated in terms of survival ratio. The effect of purification procedure on the spore morphology was investigated with electron microscopy. The CLH purification process significantly damages spore coats and increases the susceptibility of Bacillus spores to UVA radiation and photocatalytic inactivation. It is therefore likely that the survival of CLH treated spores in extra-terrestrial environments would be less than that of the same spores purified by a less aggressive procedure.

Since the first discovery of a Jupiter-mass planet in 1995 more than 2000 exo-planets have been found to exist around main sequence stars. The detection techniques are based on the radial velocity method (which involves the measurement of the star's wobbling induced by the gravitational field of the orbiting giant planets) or on transit photometry by using space telescopes (Kepler, Corot, Hubble and Spitzer) outside the absorbing Earth atmosphere. From the ground, as infrared observations are strongly limited by atmospheric absorption, radioastronomy offers almost the only possible way to search for water presence and abundance in the planetary atmospheres of terrestrial-type planets where life may evolve. Following the discovery in 1994 of the first water maser emission in the atmosphere of Jupiter induced by a cometary impact, our measurements have shown that the water maser line at 22 GHz (1.35 cm) can be used as a powerful diagnostic tool for water search outside the solar system, as comets are able to deliver considerable amounts of water to planets raising the fascinating possibility of extraterrestrial life evolution. Thus in 1999 we started the systematic search for water on 35 different targets up to 50 light years away from the Sun. Here we report the first detection of the water maser emission from the exoplanetary systems Epsilon Eridani, Lalande 21185 and Gliese 581. We have shown the peculiar feasibility of water detection and its importance in the search for exoplanetary systems especially for the Astrobiology programs, given the possibility of long period observations using powerful radiotelescopes equipped with adequate spectrometers.

The Earth's atmosphere and the Earth's magnetic field protects local life by shielding us against Solar particle flows, just like the sun's magnetic field deflects cosmic particle radiation. Generally, magnetic fields can affect terrestrial life such as migrating animals. Thus, terrestrial life is connected to astronomical interrelations between different magnetic fields, particle flows and radiation. Mass strandings of whales have often been documented, but their causes and underlying mechanisms remain unclear. We investigated the possible reasons for this phenomenon based on a series of strandings of 29 male, mostly bachelor, sperm whales (Physeter macrocephalus) in the southern North Sea in early 2016. Whales’ magnetic sense may play an important role in orientation and migration, and strandings may thus be triggered by geomagnetic storms. This approach is supported by the following: (1) disruptions of the Earth's magnetic field by Solar storms can last about 1 day and lead to short-term magnetic latitude changes corresponding to shifts of up to 460 km; (2) many of these disruptions are of a similar magnitude to more permanent geomagnetic anomalies; (3) geomagnetic anomalies in the area north of the North Sea are 50–150 km in diameter; and (4) sperm whales swim about 100 km day−1, and may thus be unable to distinguish between these phenomena. Sperm whales spend their early, non-breeding years in lower latitudes, where magnetic disruptions by the sun are weak and thus lack experience of this phenomenon. ‘Naïve’ whales may therefore become disoriented in the southern Norwegian Sea as a result of failing to adopt alternative navigation systems in time and becoming stranded in the shallow North Sea.

M-dwarf stars are more abundant than G-dwarf stars, so our position as observers on a planet orbiting a G-dwarf raises questions about the suitability of other stellar types for supporting life. If we consider ourselves as typical, in the anthropic sense that our environment is probably a typical one for conscious observers, then we are led to the conclusion that planets orbiting in the habitable zone of G-dwarf stars should be the best place for conscious life to develop. But such a conclusion neglects the possibility that K-dwarfs or M-dwarfs could provide more numerous sites for life to develop, both now and in the future. In this paper we analyse this problem through Bayesian inference to demonstrate that our occurrence around a G-dwarf might be a slight statistical anomaly, but only the sort of chance event that we expect to occur regularly. Even if M-dwarfs provide more numerous habitable planets today and in the future, we still expect mid G- to early K-dwarfs stars to be the most likely place for observers like ourselves. This suggests that observers with similar cognitive capabilities as us are most likely to be found at the present time and place, rather than in the future or around much smaller stars.

Al Wahbah Crater, located in a remote area in western Saudi Arabia as part of The Harrat extinct volcanic chain, is 2 km wide with a depth of 250 m. It is registered by the General Commission for Tourism and National Heritage as an ancient and archaeological site. The crater is subjected to extreme environmental conditions as its bottom is rarely subjected to rainfall and mudflows. Because of high temperature, high evaporation rates and extremely limited rainfall, the crater leaves behind dried thick white sodium phosphate crystals. Here, we studied the chemical composition and the microbial community composition using 16S rRNA pyrosequencing in different vertical layers (2, 20, 40, 60, 80 and 100 cm) of the crater sediment. Total sodium concentrations were 28 000– 46 700 ppm and calcium levels were 31 400– 56 500 ppm. In addition, samples were very sulphuric, with sulphate and sulphite levels exceeding 2157 ppm and 5.54 ppm, respectively. Ferric ions concentrations were <0.2 ppm, while nitrate, ammonium and nitrite levels were <2 ppm, 1.5 ppm and 0.05 ppm, respectively. Archaea dominated the surface and the bottom, while bacteria were most common at 20–60 cm. Extremely halophilic archaea and bacteria including Halorhabdus spp. Halorubrum spp., Salinibacter iranicus and Halorhodospira halophila were identified in all samples. Moreover, the relative abundance of Halanaerobiaceae accounted for 22% of the species in the top of the crater. S. iranicus and species belonging to Halorhabdus and Halorubrum that were identified between 60 and 100 cm could be considered as extreme organisms.

Suppose that advanced civilizations, separated by a cosmological distance and time, wish to maximize their access to cosmic resources by rapidly expanding into the universe. How does the presence of one limit the expansionistic ambitions of another, and what sort of boundary forms between their expanding domains? We describe a general scenario for any expansion speed, separation distance and time. We then specialize to a question of particular interest: What are the future prospects for a young and ambitious civilization if they can observe the presence of another at a cosmological distance? We treat cases involving the observation of one or two expanding domains. In the single-observation case, we find that almost any plausible detection will limit one's future cosmic expansion to some extent. Also, practical technological limits to expansion speed (well below the speed of light) play an interesting role. If a domain is visible at the time one embarks on cosmic expansion, higher practical limits to expansion speed are beneficial only up to a certain point. Beyond this point, a higher speed limit means that gains in the ability to expand are more than offset by the first-mover advantage of the observed domain. In the case of two visible domains, it is possible to be ‘trapped’ by them if the practical speed limit is high enough and their angular separation in the sky is large enough, i.e. one's expansion in any direction will terminate at a boundary with the two visible civilizations. Detection at an extreme cosmological distance has surprisingly little mitigating effect on our conclusions.

In this paper, we revisit the Dysonian approach and assume that a superadvanced civilization is capable of building a cosmic megastructure located closer than the habitable zone (HZ). Then such a Dyson Sphere (DS) might be visible in the optical spectrum. We have shown that for typical high melting point metamaterial – Graphene, the radius of the DS should be of the order of 1011 cm, or even less. It has been estimated that energy required to maintain the cooling system inside the DS is much less than the luminosity of a star. By considering the stability problem, we have found that the radiation pressure might stabilize dynamics of the megastructure and as a result it will oscillate, leading to interesting observational features – anomalous variability. The similar variability will occur by means of the transverse waves propagating along the surface of the cosmic megastructure. In the summary, we also discuss the possible generalization of the definition of HZs that might lead to very interesting observational features.

One of the primary open questions of astrobiology is whether there is extant or extinct life elsewhere the solar system. Implicit in much of this work is that we are looking for microbial or, at best, unintelligent life, even though technological artefacts might be much easier to find. Search for Extraterrestrial Intelligence (SETI) work on searches for alien artefacts in the solar system typically presumes that such artefacts would be of extrasolar origin, even though life is known to have existed in the solar system, on Earth, for eons. But if a prior technological, perhaps spacefaring, species ever arose in the solar system, it might have produced artefacts or other technosignatures that have survived to present day, meaning solar system artefact SETI provides a potential path to resolving astrobiology's question. Here, I discuss the origins and possible locations for technosignatures of such a prior indigenous technological species, which might have arisen on ancient Earth or another body, such as a pre-greenhouse Venus or a wet Mars. In the case of Venus, the arrival of its global greenhouse and potential resurfacing might have erased all evidence of its existence on the Venusian surface. In the case of Earth, erosion and, ultimately, plate tectonics may have erased most such evidence if the species lived Gyr ago. Remaining indigenous technosignatures might be expected to be extremely old, limiting the places they might still be found to beneath the surfaces of Mars and the Moon, or in the outer solar system.

In this paper is proposed a new theory concerning the formation of the first proteinogenic amino acids and their corresponding polypeptides starting of three syntones: methylene, nitrene and carbon monoxide. First, at low temperature in nitrogen, these three syntones form aziridinone, an asimetric compound in special conditions. Next, by a series of radical chain, izomerization, cyclization, elimination and polymerization reactions, apparently without a well defined transition states are formed a series of precursor syntones. Finally, these more structured syntones at the contract with the components of primary atmosphere, especially with water, ammonia, hydrogen sulphide, even with carbon dioxide and methane offer the first proteinogenic amino acids and their first corresponding polypeptides. As a very important aspect, the aziridinone cycle furnish the backbone of proteinogenic amino acids. The formation of each proteinogenic amino acid moiety also as its participation to construction of polypeptide structures were estimated by two parameters: (1) the complex structural factor, Fe and (2) the participation coefficient, Cp respectively. Dominantly, the quantitative results given in this paper were acquired by structural, thermodynamical and reactivity studies using DGauss with the B88-LYP GGA energy functional with high integral accuracy. Finally, an experimental assembly for obtention of amino acids and polypeptides is proposed. Brief, the three initial syntones: CH2, NH and CO, in nitrogen form aziridinone. That, in reactions with the same three syntones form, the more structured syntone precursors of proteinogenic amino acids and polypeptides. At the contact with primary atmosphere components are formed the first proteinogenic amino acids and polypeptides. The first polypeptides appear from polypeptide precursors and not from proteinogenic amino acids.

The investigation of Gale Crater has highlighted the occurrence of lake sediments in the geological record of Mars. Lacustrine basins include a diversity of potential habitats for life. An analogue terrestrial lacustrine basin of Devonian age in Scotland contains sulphide minerals in several settings where subsurface microbial colonization can be envisaged. Sulphur isotope compositions for the sulphides imply that they were precipitated by microbial sulphate reduction. The data suggest that the search for life in martian lacustrine basins should include investigation of potential subsurface habitats, and that any sulphides in martian lacustrine basins could be useful indicators in the search for life.

To test the rate at which a lifeless but habitable environment (uninhabited habitat) can be colonized, artificial endolithic habitats were constructed in the laboratory and exposed to the natural environment. They were composed of sterile stacked sintered glass discs (stacks) containing CHNOPS elements, liquid water, energy and a carbon source, making them habitable for aerobic respiring organisms and phototrophs. One set of stacks was exposed fully to atmospheric conditions and one set was covered from direct overhead atmospheric input and precipitation. The process of colonization was heterogeneous across the stacks. After 3 months, all uninhabited habitats were colonized at all depths in both fully exposed and covered stacks. However, uninhabited habitable conditions persisted in covered stacks after 1 month, demonstrating the importance of the hydrological cycle in the connection between inhabited habitats and uninhabited habitats. Low porosity rocks were found to retard the extent of colonization compared with higher porosity rocks. Examination of genomic DNA demonstrated that the habitats were colonized by a community dominated by Proteobacteria. Covered stacks had a higher abundance of fungal sequences among eukaryotic colonizers. These data demonstrate the tight coupling between the appearance of habitable conditions and life and the reasons for the rarity of uninhabited habitats on the present-day Earth. On other planetary bodies, such as Mars, with more inclement atmospheres and less vigorous hydrological cycles or a lack of life, uninhabited habitats could persist for longer with consequences for the interpretation of data sent back by planetary science missions.