Select Accomplishments 2009-2014 (CAN5)
Between 2009–2014 our team published 245 papers, and 12 books or book chapters; presented 185 papers at conferences; and produced two Masters theses, with 5 PhD theses in progress for completion in 2014. We hosted 7 graduate students, 17 postdoctoral fellows, and 3 affiliated fellows for a total of 24.8, 36.4, and 9.0 FTE years, respectively. We additionally had 3 affiliated graduate students (8 yrs FTE) and hosted 2 NASA Postdoctoral fellows. Most of our fellows have moved to prestigious fellowships, or permanent positions.
- Biology – Developed four autonomous GeoMICROBE instrument sleds and used them to collect hydrothermal fluids from drillholes in the basaltic seafloor, where H2O and CH4 are the principal electron donors and dissolved organic matter comprises new and degraded materials. We observed a large change in the microbial community during CAN-5.
Derived evidence to explain life’s choice of 20 amino acids and showed that (1) amino acid similarity within proteins is rooted in physico-chemistry, (2) abiotically plausible amino acids within the modern code were insufficient to form proteins in early life, and (3) amino acid molecular descriptors within proteins can be categorized by their interdependence and relative importance. Found Earth-like concentrations of boron in Martian clay; boron is implicated in the origin of life.
- Comets, MBCs, Asteroids, and KBOs – Discovered 5 Main Belt Comets and developed a theory for their origin. Determined the rotational period, activity, parent volatiles, and particle size distribution for several comets, main belt comets, asteroids, and Kuiper Belt Objects, and demonstrated that CO2 is a major driver of comet activity. Determined the size distribution of Jupiter-family comets and Centaurs.
- Earth, Moon, and Mars – Developed a method for measuring H2O and D/H with the Cameca 1280 ion microprobe and used it on minerals from Iceland, Baffin Island, and the Hawai’i deep drill core, in late-differentiation lunar rocks, in Martian meteorites, and synthesized at high pressure, to determine (1) the solubility of water at the 410 km discontinuity in Earth’s mantle, (2) a D/H value for the primitive mantle lower than any previously measured, (3) that the lunar interior contains heterogeneous reservoirs of water content and D/H ratio, (4) that Earth and Mars have similar primitive D/H ratios and so were produced from the same source, (5) that the nakhlite meteorites inherited their D/H ratio from the Martian atmosphere and so were altered as part of the Martian hydrologic cycle.
Demonstrated that the Moon contains the same abundances of refractory elements as Earth, but is depleted by 99% in highly volatile elements. Studied delivery and storage of water on the Moon and subsurface ice and Ice Age cycles on Mars, developed models for the origin of Earth’s water and the formation of Mars, and wrote review articles on the bulk composition of Mars and on water in the Moon. We led an analysis to impact the Herschel Space Telescope into a lunar polar region to search for buried volatiles.
- Exoplanets and Habitability – Discovered a) 11 extrasolar planets, including Gliese 581g, a candidate habitable planet, and GJ 667Cc, the first confirmed super-Earth in the habitable zone; and b) three circumbinary planets, including the first circumbinary planetary system, Kepler 47b&c and Kepler 38b. Developed models for evolution of circumprimary and circumbinary planetary systems and their habitable zones. Integrated exoplanet formation rates and supernova surveys into computational models and found that the inner disk of the Milky Way may be most habitable for complex life.
- HI-SEAS – Completed the first 4 month mission for Hawai’i Space Exploration Analog and simulation (hi-seas.org), focused on long-duration space exploration life-support systems.
- Informatics – Analyzed thousands of astrobiology publications and (1) investigated the role of co-localization on interdisciplinarity, using the UHNAI as a test case; (2) yielded metrics of interdisciplinary potential for researchers and teams; (3) visualized interdisciplinarity of UHNAI researchers, the publication patterns of teams, and their alignment with Astrobiology Roadmap goals; (4) found areas of commonality between UHNAI researchers and NAI teams by identifying crossover documents; (5) created a dynamic, scalable document clustering process to catalyze interdisciplinary science within and beyond astrobiology; (6) developed metrics of interdisciplinarity and a new selection algorithm to optimize document analysis via the information bottleneck method. Evaluated public perception of astrobiology in social media, and rebuilt and recalibrated the UHNAI 3D visualization cave.
- Interstellar Medium and Kuiper Belt Ices – Discovered novel reaction mechanisms by which H2O forms in the interstellar medium and Solar System via proton bombardment of inorganic ices. Showed how the spectroscopic signatures of H2O and NH3-bearing ices depend on the temperature and the ice physical and chemical state. Mapped reaction pathways for (1) astrobiologically important molecules in astrophysically relevant ices, including HCN and related species; CO and CO2 as building blocks for sugars, carboxylic acids, and aldehydes; (2) the formation of amines, amides, and amino acids; (3) ozone and its underlying isotope effects; (4) molecular hydrogen and its diffusion-limited and suprathermal reactions; and (5) formation of alkylphosphonic acids, which are key carriers of prebiotic phosphorous.
- Meteorites – Showed (1) that CR chondrites are breccias which contain aqueously altered material; (2) that a CR1 chondrite was altered several million years after the CR2 chondrites, and that the Sutters Mill anomalous CM chondrite was altered at the same time as other CM chondrites; (3) that secondary fayalite formed by aqueous alteration on the ordinary and carbonaceous parent bodies, ~2.5 and 4-5 Myr after CV CAIs, respectively; (4) that chondrule olivine and secondary fayalite and magnetite in carbonaceous and ordinary chondrites formed at 100-200°C from water ices which originated locally within the inner Solar System; (5) that graphitic material in chondrites was spectroscopically homogeneous in aqueously altered CR chondrites; and (6) the source of organic material in aqueously altered CR chondrites, and why morphology changes with alteration.
- Young Stars – Obtained light curves for ~104 young stars with an in-house developed small telescope robotic system, VYSOS. Carried out >200,000 numerical simulations of newborn triple star systems inside dense molecular cloud cores. Developed a new theory for wide binary formation through the dissolution and unfolding of newborn triple systems. Carried out extensive surveys to find very low-mass companions to protostars driving major Herbig-Haro flows. Carried out near-infrared and submillimeter surveys of selected young multiple star systems and detected new rotating disk candidates, yielding some of the youngest circumstellar disks found. Studied optical spectra of a Herbig Ae/Be star to bridge the transition between formation of low and high-mass stars and probe star formation in clusters.
Select Accomplishments 2003-2008 (CAN3)
We pioneered a concept for fostering interdisciplinary research through the implementation of the “Water Hole”, a suite where our cadre of Postdoctoral Fellows worked in a communal environment. During the five years of CAN3 our group published 235 research papers, over 80 conference presentations, 3 books, over 60 public talks, and took the lead in organizing and running 5 major conferences (~1600 participants), 5 focused interdisciplinary astrobiology workshops (250 participants), 6 special sessions at major conferences, and numerous news interviews. This science effort was coupled with strong outreach and graduate and undergraduate programs involving over 225 teachers and students interacting with nearly 80 astrobiologists.
- We unraveled experimentally in a surface scattering machine how astrobiologically important molecules like sugars and aminoacids can be formed in low-temperature interstellar and solar system ices by galactic cosmic ray processing.
- We investigated the role of binarity and multiple stars in early stellar evolution; in particular, how disk interactions in binary systems can lead to violent outbursts in young stars.
- We have shown that the extension of the current theories of terrestrial planet formation to other planetary systems predicts the existence of habitable planets in extreme planetary environments and the possibility of their detection.
- We designed, constructed and tested a deep down-hole borehole sampler and a seafloor instrument sled for geomicrobiological studies of basement fluids.
- We led a rapid response expedition to a mid-ocean ridge eruption, documenting the emplacement of new lava flows the changes in geochemical character of the hydrothermal fluids, and changes in the microbial diversity of hydrothermal plumes.
- We participated in an expedition to a hydrothermally active seafloor seamount (Loihi Seamount). We developed and successfully employed an in situ electrochemical analyzer with micro-manipulated electrodes.
- We conducted a search for H3+ from the atmospheres of hot Jupiters, set limits on the H3+ emission from each of these systems, and compared them with models in the literature.
- We showed that grain surface chemistry can selectively deuterate a specific set of molecules while having little fractionation effect on the rest of the grain mantle population. More specifically, we have shown that methanol and its isotopologues are significantly deuterated when compared to water.
- When investigating the Metazoan Phylogeny, detailed knowledge of the phylogenetic relationships among the extant animal kingdom and their eukaryotic relatives is critical for understanding
the origin of complex life. We found that in at least half of the gene families, even the best-fit model of sequence evolution could not adequately describe the evolution of the sequence data from the taxa.
- We made important gains in understanding the inorganic origin of methane from dissolved carbonate during serpentinization in terrestrial subduction zones, and its subsequent use by Archaea, which oxidize it anaerobically using seawater sulfate.
- In the context of the coldtrapping phenomenon on the Moon, we investigated subsurface migration of water molecules within the lunar regolith.
- We found that star-planet interactions that probe extrasolar planetary magnetic fields have an important on/off characteristic of the coupling that depends on the stellar magnetic fields.
- Our models suggest that in star forming regions carbon dioxide cannot form by reaction of atomic oxygen with carbon monoxide as this requires a large fraction of atomic oxygen to be locked-up in molecular oxygen, which is inconsistent with the observations.
- Installation of the Cameca ims 1280 ion microprobe and a
Witec Confocal Raman scanning system in the W. M. Keck Cosmochemistry laboratory has been a major step in providing infrastructure for sample-based studies related to astrobiology and cosmochemistry.
- With regard to the role of topography for seasonal and permanent ground ice on Mars, we documented spacecraft observations of seasonal frost on crater slopes, at latitudes substantially farther equatorward than the continuous seasonal polar caps.
- We carried out large-scale model calculations of permanent ice stability (including planetary topographic roughness) and produced a global map of Mars’ expected ice distribution.
- We evaluated meteorological data to determine accurately the sublimation loss in the Antarctic Dry Valleys under various environmental conditions and we modeled the effect of wind on ice loss.
- We investigated ice migration in sublimation environments as a physical process. Several theoretical studies have been carried out to shed light on mid-latitude ice on Mars, ice in the Dry Valleys of Antarctica, and in the laboratory simulations of these environments.
- We modeled the history of hemispheric subsurface ice layers on Mars over the last few million years, developed a new numerical method, and explained the present-day geographic distribution of ice on Mars.
- Images from the MGS spacecraft and image surveys revealed how slope-streaks have changed since seen in Viking Orbiter images. This lead to the first observation of slope streak fading and the discovery that bright slope streaks form from old dark slope streaks.
- We systematically estimated the rate of ice retreat from bodies in the main asteroid belt and identified parameter regions where buried ice can survive over the age of the solar system.
- Molecular analysis of seawater collected from the epi- (10 m), meso- (800 m) and bathypelagic (4400 m) components of the water column the Hawai’i Ocean Time-Series Station ALOHA provided exciting insights into environmental factors that shape the assembly of microbial communities. Analysis of highly discriminatory molecular markers identified, for the first time, evidence of tropical endemicity in marine bacteria.
- We studyied a microbial biofilm growing at low light intensities below the entrance of a lava cave in Kilauea Crater, Hawaii Volcanoes National Park.
- A new hot water drill for sampling sub-glacial lakes in Iceland was constructed and used in an expedition to the western and eastern Skaftarkatlar subglacial lakes in Iceland. Data were obtained on the temperature profile and geochemistry of the lake. The western lake’s microbial community consists entirely of psychrotolerant bacteria with low diversity.
- We investigated the role that water ice plays in the activity of comets on their inbound trajectories at large heliocentric distances. By combining comet observations with vacuum experiments on amorphous, gas-laden ice samples we find that annealing processes in water ice between 35-120K can cause activity at large distances.
- In support of the Deep Impact mission, a major international ground-based observing campaign was orchestrated. As part of this, we obtained the first high-resolution spectropolarimetric measurement of a comet, the Deep Impact target, before, during, and after impact.
- We identified a new class of comet in the outer asteroid belt, the Main Belt Comets, with possibly great relevance to the origin of planetary water.
- We conducted observational work to look for ices, organics, and the products of aqueous alteration in several outer solar system Kuiper Belt objects. Water absorption was detected, but we saw no features indicative of the presence of hydrated minerals.
- Coarse grained objects in carbonaceous chondrites, (chondrules and CAIs), are surrounded by a rim of fine-grained materials. Analysis suggests that the formation of the rims must have happened just before or during accretion of the final parent asteroid, similar to the run-away accretion models suggested by radioactive dating of differentiated bodies.
- In our work on the adaptivity of extremophilic proteins, we were able to develop a new comparative proteomics strategy. Eight hundred different amino acid motifs that correspond to potential helix stabilizing or destabilizing interactions showed relationships between organisms and their environment.
- We developed a novel remote detection technique for searching for extraterrestrial life, and developed an equation that can be used to predict the likelihood of observing an induced chiral signal in circularly polarized light that is based on factors such as object albedo and potential cell densities in ice.
- We obtained primitive basalt samples from Iceland that contained mantle derived phenocrysts containing trapped melt inclusions over a range of geographic distribution representing the mantle plume as well as mid-ocean ridge derived magmatism in Iceland. This is in preparation for the work presented in this proposal.Our interdisciplinary astrobiology research experiment is working. Out of this nexus of activities, new ideas have emerged that are leading to new truly interdisciplinary research initiatives.