2011 Annual Science Report

University of Hawaii, Manoa Reporting  |  SEP 2010 – AUG 2011

Executive Summary

Overview

Water is the medium in which the chemistry of all life on Earth takes place and is likely to be equally important for Astrobiology in general. Our research combines a set of interdisciplinary studies that range from the interstellar medium to the interior of planet Earth, all designed around “Water and Habitable Worlds”. Our 5-year plan includes the following research areas:

  • We don’t know where the water on Earth came from. It may have arrived trapped as gas adsorbed on dust grains as the planet accumulated mass, or it may have formed via chemical reactions on the early magma ocean, or water may have been delivered exogenously. Un-derstanding the relative roles of each source will require astronomical observations, ice laboratory experiments, chemical and dynamical models as well as geochemical observa-tions. The D/H ratio of Earth, including its bulk value in the mantle ...

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Field Sites
34 Institutions
22 Project Reports
69 Publications
23 Field Sites

Project Reports

  • VYSOS Construction

    The VYSOS project aims at surveying all the major star forming regions across the entire northern and southern sky for variable young stars.using two small telescopes and robotics.
    As instrument implementation continues, We are working with Timm Riesen and Karen Meech to study the evolution of comet tails and to improve data relating to comet-focused missions.

    ROADMAP OBJECTIVES: 1.2
  • Deep (Sediment-Buried Basement) Biosphere

    The ocean crust comprises the largest aquifer on earth. Deep sediment cover provides an environ-ment for a unique biosphere hosting microorganisms surviving under extreme conditions. Frac-tured rock provides abundant surfaces that can be colonized by diverse microbes and water-rock reactions promote chemical conditions that influence key geochemical cycles within the Earth’s crust and oceans. Team members participated in a 14-day research cruise to study the sediment-buried basement (basaltic crust) biosphere, to provide unprecedented and unique insight into the mobility and origin of microorganisms within this remote biosphere.

    ROADMAP OBJECTIVES: 4.1 4.2 5.2 5.3 6.1 6.2 7.1 7.2
  • Ice Chemistry of the Solar System

    The overall goals of this project are to understand the chemical evolution of the Solar System, in particular leading to the development of astrobiologically important molecules. This is being achieved by investigation the formation of key organic carbon-, hydrogen-, oxygen-, and nitrogen-bearing (CHON) molecules in ices of Kuiper belt objects by reproducing the space environment experimentally in a unique ultra-high vacuum surface scattering machine. During this reporting period, our team worked on six projects towards our research goal to better understand the ice-based astrochemistry of chemical synthesis for carbon-containing compounds within the solar system. The Keck Astrochemistry Laboratory was also completed during this reporting period.

    ROADMAP OBJECTIVES: 1.1 2.2 3.1 3.2 3.3 6.2 7.1
  • Surfaces of Trojan Asteroids

    With a total mass similar to the main asteroid belt, the Trojan asteroids are a major feature in the solar system. Thermal infrared (TIR) emission spectra of Trojan asteroids obtained with the Spitzer space telescope exhibit a 10-µm emissivity plateau that closely resembles the emission feature of active comets. This result is very puzzling because the light scattering properties of a regolith aster-oid surface is significantly different from a diffuse dust cloud of comet. It has been suggested that the Trojan surfaces may consist of fine-grained silicates suspended in a transparent matrix.

    ROADMAP OBJECTIVES: 2.2
  • Small Body Missions

    The team has been active in coordinating and executing Earth-based observations in support of two extended Discovery missions to comets: EPOXI and StardustNExT. These missions re-used the spacecraft from two previously successful missions to fly past new targets. The Earth-based observations were used for mission planning and development, and to give us a time baseline of observations with instruments and at wavelengths not possible during a fast flyby with limited instrumentation. The ground-based and Earth-orbital data plays a critical role in the interpretation and understanding of the in-situ data obtained by the spacecraft. The EPOXI flyby of comet 103P/Hartley 2 on 4 November 2010 revealed a small, highly active comet with CO2-driven jets and a swarm of icy chunks surrounding the nucleus, and the StardustNExT flyby of comet 9P/Tempel 1 on 14 February 2011 allowed us to visit a comet nucleus for the second time to look for changes on the surface after it had made one orbit around the sun.

    ROADMAP OBJECTIVES: 2.2
  • Solar System Icy Body Thermal Modeling and Evolutionary Pathways

    Thermal processing on small icy bodies in the solar system (comets, asteroids, Kuiper belt objects) will cause the volatile composition and interior structure to change over time. We seek to understand the evolutionary processes in these bodies so we can understand the observations made in the present epoch and to what extent we can infer the earliest stages of the solar system from these objects.

    ROADMAP OBJECTIVES: 1.1 2.2 3.1
  • Measurements of Primitive Water

    Our research goal is to collect and analyze water that may sample the primordial water accreted by the Earth. This primordial water may reside at the bottom of the Earths mantle and may be sampled from “hotspot” volcanism such at that occurring in Iceland and Hawaii. Glass melt inclusions inside olivine crystals that formed at depth before the lava interacted with surface waters give us the best chance to find this primordial water.

    ROADMAP OBJECTIVES: 1.1 3.1
  • Ice Chemistry Beyond the Solar System

    The molecular inventory available on the prebiotic Earth was likely derived from both terrestrial and extraterrestrial sources. Many molecules of biological importance have their origins via chemical processing in the interstel-lar medium, the material between the stars. Polycyclic aromatic hydrocarbons (PAHs) and related species have been suggested to play a key role in the astrochemical evolution of the interstellar medium, but the formation mechanism of even their simplest building block, the aromatic ben¬zene molecule, has remained elusive for decades. Formamide represents the simplest molecule contain-ing the peptide bond. Conse¬quently, the formamide molecule is of high interest as it is considered as an important precursor in the abiotic synthesis of amino acids, and thus significant to further prebiotic chemistry, in more suitable environments. Ultra-high vacuum low-temperature ice chem-istry experiments have been conducted to understand the formation pathways in the ISM for many astrobiologcally important molecules.

    ROADMAP OBJECTIVES: 1.1 1.2 3.1 3.2 3.3 6.2 7.1
  • Permafrost in Hawaii

    We investigate microclimates on the Hawaiian Islands that serve as possible analogues to Mars. The summit of Mauna Kea is exceptionally dry, but sporadic permafrost exists in cinder cones near the summit. Additionally, ice caves are known to exist on the flanks of Mauna Loa. They are the world’s most isolated ice caves. Theoretical models have been developed for microclimatic effects in craters and caves. Preparations for upcoming fieldwork have been made and interdisciplinary collabora-tions have been developed.

    ROADMAP OBJECTIVES: 2.1 5.3 6.2
  • Main Belt Comets

    The distribution of volatiles, and in particular water, in our solar system is a primary determinant of solar system habitability, and understanding how volatiles were distributed throughout the solar system during the era of planetary formation. In particular, the origin of terrestrial water is a fundamental unresolved planetary science issue. There are three leading scenarios for its origin: direct capture from nebular gas, delivery from icy planetesimals, and chemical reactions between oxides in a magma ocean and a tenuous hydrogen atmosphere. Comets provide one of the mechanisms for large-scale transport and delivery of water within our solar system, and asteroids provide another source of volatiles. However, neither comets nor asteroids can explain both Earth’s water and its noble gas inventory. A recently discovered new class of icy bodies in the outer asteroid belt, the Main Belt Comets (MBCs), are comets in near-circular orbits within the asteroid belt that are dynamically decoupled from Jupiter. Dynamics suggest they formed in-situ, beyond the primordial snow line, and as such represent a class of icy bodies that formed at a distance from the Sun that has not yet been studied in detail and which could potentially hold the key to understanding the origin of water on terrestrial habitable worlds. The UH NAI team has been very active in searching for additional MBCs, and characterizing those that are known.

    ROADMAP OBJECTIVES: 1.1 2.2 3.1
  • Comet Activity and Composition

    The study of primitive bodies as building blocks of the Solar System, and what they contribute to
    the understanding of how the Solar System was constructed is central to the science goals laid out in the Planetary Decadal Survey. Objects in the Kuiper belt (KBOs) are remnant planetesimals with orbits beyond Neptune, with sizes small enough that they are relatively well preserved since the era of solar system formation. KBO surfaces exhibit a wide variety of colors, ranging from blue-neutral to reddish. This reflects both the underlying primordial chemical differences as well as radiation processing on their surfaces. Some of this population gets scattered into the inner solar system through dynamical interactions, and these, when observable form the Centaur class of objects. Comets, depending on their source region may have formed at a variety of distances and scattered early in the solar system’s history; some are now captured in the inner solar system due to the influence of Jupiter. Understanding the chemistry of these primordial leftovers is important as a clue to the early conditions in the solar system during the planet formation era. Our team is actively studying the composition of these objects through spectroscopy of their surfaces and the materials outgassed, by observing the level of dust and gas objects produce when they move into the inner solar system and through modeling their outgassing behavior.

    ROADMAP OBJECTIVES: 2.2 3.1
  • Galactic Habitable Zone

    Life for certain exists in the Milky Way galaxy, however, understanding if there are certain regions in the galaxy that are more favorable to life is one of the thrusts of astrobiology. This project GHZ is described in terms of the spatial and temporal dimensions of the Galaxy that may favor the devel-opment of complex life. Of particular particular interest to astrobiologists, and to the general public, is whether or not our position in the Galaxy is favourable for the development of complex life.

    ROADMAP OBJECTIVES: 1.1 4.3
  • Solar System Dynamics

    Understanding how the planets accumulated requires a detailed investigation of the dynamical pro-cesses that were occurring at the time of accretion. UHNAI team members are using dynamical sim-ulations involving many particles to help interpret some of the observable aspects of the modern solar system.

    ROADMAP OBJECTIVES: 1.1
  • Formation and Prospect of the Detection of Habitable Super-Earths Around Low-Mass Stars

    In the quest for potentially habitable planets, the nearest stars are of special importance. These stars have accurate distances and precisely determined stellar parameters, and are the only stars for which follow-up by astrometry and direct imaging is possible. Within the Sun’s immediate neighborhood, M stars constitute the majority (72%) of nearby stars. The proximity, low surface temperatures, and small masses of these stars have made them unique targets for searching for terrestrial and habitable planets. During the past five years, team member N. Haghighipour has been actively involved in the detection of extrasolar planets around M stars both in theoretical and observational fronts.

    ROADMAP OBJECTIVES: 1.1 1.2
  • Beyond the Drake Equation: Can We Find New Integrative Frameworks for Astrobiology Research?

    The Drake equation (in its current formulation) is a scheme used to estimate the number of detectable intelligent aliens around us. It does so by collecting together what is considered as the leading terms that represent what we know about astronomy, planetary science, biological evolution and social de-velopment. However, after ~50 years of rapid scientific progress, much of what we have discovered challenges us to either improve our estimates of the factors in Drake’s equation, re-work the equation according to current knowledge in the field of astrobiology, or change the question that we are asking and the way we ask them altogether.

    ROADMAP OBJECTIVES: 7.1 7.2
  • Lunar Water, Volatiles, and Differentiation

    Recent discoveries of water in the Moon have important implications for how and when water was delivered to Earth. One way of investigating this is to determine how much water the Moon had when it formed. We do this by searching for water in rocks rich in trace elementsSo far our results indicate that either Earth experienced a second gain of water after the moon formed, or there was an as-yet unexplained loss from the proto-lunar disk.

    ROADMAP OBJECTIVES: 1.1
  • Mars Bulk Composition and Aqueous Alteration

    The composition of Mars, including its total inventory of water, is central to understanding how Mars and the other inner planets formed. Comparison between the abundances of water and volatile elements in Mars, Earth, and Moon are particularly important to understand the source of water to the Earth. We study Martian meteorites, to develop criteria for distinguishing terrestrial from Martian weathering, as a step towards defining the compositions of water solutions on Mars. Our initial results indicate that the martian interior has D/H similar to terrestrial mean ocean water, suggesting similar sources of water to both planets.

    ROADMAP OBJECTIVES: 1.1 2.1
  • Water in Planetary Interiors

    We have synthesized samples of high pressure mineral phases that are likely hosts for H, and thus water, in planetary interiors, and measured physical properties including crystal structure, density, elasticity, and electrical conductivity to see if there is evidence of deep hydration in the Earth.

    ROADMAP OBJECTIVES: 1.1 2.1 3.1 3.2
  • Cosmochemical Search for the Origin of Water in Planetary Bodies

    The ultimate goal of our study is to understand the origin of water in planetary bodies (asteroids, comets and terrestrial planets). In particular we want to understand better the water-based chemis-try that happens on these bodies. This gives important insights into the role(s) played by water dur-ing the origin of our Solar System. We are taking a new approach to understanding aqueous altera-tion processes in carbonaceous chondrites by investigating the distribution and composition of or-ganic compounds in aqueously altered chondrites. This research will also shed light on the nature of organic compounds in asteroids and in planetesimals that might have delivered organic compounds to the early Earth. This research will use a variety of micro-analytical techniques (optical microscopes, scanning electron microscope, electron microprobe, transmission electron microscope, ion microprobe, Raman spectroscopy) to investigate the aqueous alteration that has affected the CR chondrites. These meteorites were chosen because they exhibit a complete series of alteration, from very lightly altered to completely altered, and they have experience almost no thermal metamorphism.

    ROADMAP OBJECTIVES: 1.1 2.1 2.2 3.1 3.2
  • AIRFrame Technical Infrastructure and Visualization Software Evaluation

    We have analyzed over four thousand astrobiology articles from the scientific press, published over ten years to search for clues about their underlying connections. This information can be used to build tools and technologies that guide scientists quickly across vast, interdisciplinary libraries towards the diverse works of most relevance to them.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 3.1 3.2 3.3 3.4 4.1 4.2 4.3 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • Amino Acid Alphabet Evolution

    We study the question why did life on this planet “choose” a set of 20 standard building blocks (amino acids) for converting genetic instructions into living organisms? The evolutionary step has since been used to evolve organisms of such diversity and adaptability that modern biologists struggle to discover the limits to life-as-we-know-it. Yet the standard amino acid alphabet has remained more or less unchanged for 3 billion years.
    During the past year, we have found that the sub-set of amino acids used by biology exhibits some surprisingly simple, strikingly non-random properties. We are now building on this finding to solidify a new insight into the emergence of life here, and what it can reveal about the distribution and characteristics of life elsewhere in the universe.

    ROADMAP OBJECTIVES: 3.1 3.2 4.1 4.2 4.3 5.2 5.3 6.2 7.1
  • Analogue Environment Deployments on the Big Island

    We are using the saddle region on the Big Island of Hawaii, in collaboration with NASA teams and the Canadian Space Agency in order to test technology related to sustainable living on the moon. My group will evaluate the utility of 3-D visualization in robotic navigation, in particular for the ex-ploration of lava tubes.

    ROADMAP OBJECTIVES: 1.1 2.1 4.1 4.3 6.1 6.2 7.1