2009 Annual Science Report
Astrobiology Roadmap Objective 1.1 Reports Reporting | JUL 2008 – AUG 2009
Roadmap Objective 1.1—Formation and evolution of habitable planets.
Project Reports
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AIRFrame Technical Infrastructure and Visualization Software Evaluation
To create visualizations of interdisciplinary relationships in the field of astrobiology, this component of the AIRFrame project involves creating a data model for source documents, a database structure, and evaluating off-the-shelf visualization software for possible application to the final project.
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 -
Project 1: Interstellar Origins of Preplanetary Matter
Astronomers have found interstellar space to be rich in the raw materials required for planets and life, including the essential chemical elements (C, N, O, Mg, Si, Fe, etc.) and compounds (water, organic molecules, and planet-building minerals). Our research is aimed at characterizing the composition and structure of these materials and the chemical pathways by which they form and evolve. The ultimate goal is to determine the inventories of protoplanetary disks around young sun-like stars, leading to a clear understanding of the processes that led to our own origins and insight into the probability of life-supporting environments emerging around other stars.
ROADMAP OBJECTIVES: 1.1 3.1 -
AbGradCon 2009
The Astrobiology Graduate Student Conference (AbGradCon) was held on the UW campus July 17 – 20 2009. AbGradCon supports NAI’s mission to carry out, support and catalyze collaborative, interdisciplinary research, train the next generation of astrobiology researchers, provide scientific and technical leadership on astrobiology investigations for current and future space missions, and explore new approaches using modern information technology to conduct interdisciplinary and collaborative research amongst widely-distributed investigators. This was done through a diverse range of activities, ranging from formal talks and poster sessions to free time for collaboration-enabling discussions, social activities, web 2.0 conference extensions, public outreach and grant writing simulations.
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 -
Coupled Evolution of Mars’ Surface Water and Interior
The delivery and availability of water on the Martian surface depends on the coupled evolution of the Martian interior and atmosphere. We developed models for the history of volcanism on Mars. We also determined the conditions under which the location of the Martian spin axis remains stable. We find that some true polar wander — motion of the spin axis — may have occurred, but not enough to explain the observed deformation of hypothesized shorelines that circumscribed a large paleo-ocean.
ROADMAP OBJECTIVES: 1.1 2.1 -
Astrobiology of Icy Worlds
Icy worlds such as Titan, Europa, Enceladus, and others may harbor the greatest volume of habitable space in the Solar System. For at least five of these worlds, considerable evidence exists to support the conclusion that oceans or seas may lie beneath the icy surfaces. The total liquid water reservoir within these worlds may be some 30 to 40 times the volume of liquid water on Earth. This vast quantity of liquid water raises two questions: Can life emerge and thrive in such cold, lightless oceans beneath many kilometers of ice? And if so, do the icy shells hold clues to life in the subsurface? We will address these questions through four major investigations namely, the habitability, survivability, and detectability of life of icy worlds coupled with “Path to Flight” Technology demonstration. We will also use a wealth of existing age-appropriate educational resources to convey concepts of astrobiology, spectroscopy, and remote sensing; develop standards-based, hands-on activities to extend the application of these resources to the search for life on icy worlds.
ROADMAP OBJECTIVES: 1.1 2.1 2.2 3.1 3.2 3.3 3.4 4.1 5.1 5.3 6.1 6.2 7.1 7.2 -
Task 1.1.1 Numerical Simulation of the Mixing of Organics and Ice During an Impact
On the Titan surface, organics can mix and react with liquid water created during an impact. A model simulation of an impact on the Titan surface will be used to estimate how long liquid water might exist after an impact, which will suggest how much reaction-forming prebiotic compounds may have occurred.
ROADMAP OBJECTIVES: 1.1 2.2 3.1 3.2 3.3 -
Astrophysical Controls on the Elements of Life, Task 1: High-Precision Isotopic Studies of Meteorites
The evolution of habitable planets may be affected by the injection of short-lived radionuclides, produced by supernova explosions, early in solar system history. In this task we are finding evidence of such injection in some of the earliest Solar System materials (calcium-aluminum-rich inclusions) and constraining the timing of early Solar System events.
ROADMAP OBJECTIVES: 1.1 3.1 -
Astrobiological Exploration of Mars
NASA spacecraft have discovered both chemical and physical evidence that liquid water once flowed on the martian surface. Close examination of the images and spectroscopic data from these spacecraft, and understanding what they tell us, are critical to selecting the best sites for future rover missions. This project aims to maximise the knowledge gained from orbiting and landed spacecraft and apply it effectively in future planning and execution of new missions.
The key questions for astrobiology are not so much “was water present?” as “what were its properties?” and “How long did it persist?” Using thermodynamic calculations, one can approach both questions, using mineral identifications made by the MER rovers and CRISM. We find that waters at Gusev and Meridiani planum grew extremely salty as evaporation proceeded, reaching conditions that would challenge known life on Earth. We also learn that in a number of places on the martian surface, minerals deposited billions of years ago as a result of water-rock interactions have seen little or no water since that time.
ROADMAP OBJECTIVES: 1.1 2.1 -
Biosignatures in Ancient Rocks
The Earth’s Archean and Proterozoic eons offer the best opportunity for investigating a microbial world, such as might be found elsewhere in the cosmos. The ancient record on Earth provides an opportunity to see what geochemical signatures are produced by microbial life and how these signatures are preserved for geological time. Researchers have recognized a variety of mineralogical and geochemical characteristics in ancient rocks (sedimentary and igneous rocks; paleosols) that may be used as indicators of: (i) specific types of organisms that lived in the oceans, lakes and on land; and (ii) their environmental conditions (e.g., climate; atmospheric and oceanic chemistry). Our project addresses the following questions: Are some or all of these characteristics true or false signatures of organisms and/or indicators of specific environmental conditions? Do a “biosignature” in a specific geologic formation represent a local or global phenomenon? How are the biosignatures on Mars and other planets expected to be similar to (or different from) those in ancient terrestrial rocks?
ROADMAP OBJECTIVES: 1.1 3.2 4.1 4.2 4.3 5.1 5.2 5.3 6.1 6.2 7.1 7.2 -
Cosmic Distribution of Chemical Complexity
This project seeks to improve our understanding of the connection between chemistry in space and the origin of life on Earth and possibly other worlds. Our approach is to trace the formation and development of chemical complexity in space, with particular emphasis on understanding the evolution from simple to complex species focusing on those that are interesting from a biogenic perspective and also understanding their possible roles in the origin of life on habitable worlds. We do this by first measuring the spectra and chemistry of materials under simulated space conditions in the laboratory. We then use these results to interpret astronomical observations made with ground-based and orbiting telescopes. We also carry out experiments on simulated extraterrestrial materials to analyze extraterrestrial samples returned by NASA missions or that fall to Earth in meteorites.
ROADMAP OBJECTIVES: 1.1 2.1 2.2 3.1 3.2 3.4 4.3 7.1 7.2 -
Biosignatures in Extraterrestrial Settings
This project looks at the evolution of the composition of gases in the cold disk from which planets form; the evolution of the atmosphere after planet formation, in particular, the role of trace gases in the early greenhouse effect; and, some aspects of the the formation and later dynamical evolution of extrasolar planets.
ROADMAP OBJECTIVES: 1.1 1.2 2.1 4.1 -
Astrophysical Controls on the Elements of Life, Task 2: Model the Chemical and Dynamical Evolution of Massive Stars
In order to understand the distribution of elements both on the scale of the Galaxy and individual solar systems we must understand the production of elements in stars and the dispersal of newly synthesized elements in supernova explosions. We are especially interested in the production and distribution of the radioactive isotope 26Al because the amount of this element present in the early Solar System may have affected the heating of planetesimals and hence their ability to retain water and deliver it to early planets. This task uses computational models of stellar evolution and supernovae with the most accurate treatments of physics available to predict the production elements by individual stars and by populations of stars over time.
ROADMAP OBJECTIVES: 1.1 3.1 -
Project 1: Looking Outward: Studies of the Physical and Chemical Evolution of Planetary Systems
We study the origin of life through a wide variety of approaches, beginning here with theoretical investigations of protoplanetary disks, the environments in which simple organic molecules first appeared and were concentrated in planetary bodies. We also study the survival of this organic matter during subsequent evolution through observations of circumstellar disks around both young and mature stars, extrasolar planetary systems, and small bodies in our Solar System, and through detailed models of planetary system formation.
ROADMAP OBJECTIVES: 1.1 1.2 2.2 3.1 -
Amino Acid Alphabet Evolution
All life on earth uses a standard “alphabet” of just 20 amino acids. Members of this alphabet links together into different sequences to form proteins that then interact to produce living metabolism (rather like the English of 26 letters can be linked into words that interact in sentences and paragraphs to produce meaningful writing). However, a wealth of scientific research from diverse disciplines points to the idea that many other amino acids are made by non-biological processes throughout the universe: put simply, we have no idea why life has “chosen” the members of its standard alphabet. Our project seeks to gather and organize the disparate information that describes these non-biological amino acids, to understand their properties and potential for making proteins and thus to understand better whether the biology that we know is a clever, predictable solution to making biology – or just one of countless possible solutions that may exist elsewhere.
ROADMAP OBJECTIVES: 1.1 3.1 3.2 3.4 4.1 4.3 5.1 5.3 6.2 7.1 7.2 -
Disks and the Origins of Planetary Systems
This task is concerned with understanding the evolution of complexity as primitive planetary bodies form in habitable zones. The planet formation process begins with fragmentation of large molecular clouds into flattened protoplanetary disks. This disk is in many ways an astrochemical “primeval soup” in which cosmically abundant elements are assembled into increasingly complex hydrocarbons and mixed in the dust and gas envelope within the disk. Gravitational attraction among the myriad small bodies leads to planet formation. If the newly formed planet is a suitable distance from its star to support liquid water at its surface, it lies within the so-called “habitable zone.” The goal of this project is to understand the formation process and identification of such life-supporting bodies.
ROADMAP OBJECTIVES: 1.1 1.2 2.1 4.3 -
Project 2: Processing of Precometary Ices in the Early Solar System
The discovery of numerous planetary systems still in the process of formation gives us a unique opportunity to glimpse how our own solar system may have formed 5 billion years ago. We use computers to simulate events called shock waves which are common in young planetary systems. These shock waves “light up” the gas and dust in young planetary systems, making it possible to observe molecules that would not be visible otherwise. Our goal is to determine whether some of the essential building blocks of life can be detected by exploiting this effect.
ROADMAP OBJECTIVES: 1.1 3.1 3.2 -
Mars in the Context of Planetary Evolution
Explaining the persistence of volcanism on Mars is a challenging target for geodynamic models. Mars and other planets within our solar system form the basis for understanding plate tectonics and habitability on rocky planets around other stars.
ROADMAP OBJECTIVES: 1.1 1.2 -
Task 1.1.2 Models of the Internal Dynamics: Formation of Liquids in the Subsurface and Relationships With Cryovolcanism
Prebiotic compounds can be formed on the Titan surface when organics mix and react with liquid water in a cryovolcanic context, where subsurface water “erupts” onto the cold surface.
ROADMAP OBJECTIVES: 1.1 2.2 3.1 3.2 3.3 -
Delivery of Volatiles to Terrestrial Planets
Terrestrial planets are too small to trap gas from the circumstellar disk in which they formed and so must be built from solid materials (rock and ices). In this task, we explore how and when Earth, Mars and other potentially-habitable worlds accumulated water and organic carbon. The main challenge is that water and organic carbon are relatively volatile elements (compared to rock and metal). Therefore, during the period of time in which solids condensed at the current position of Earth, water and carbon would have been mainly in the gas phase. Getting these materials to earth required that inward transportation of material from further out in the disk.
ROADMAP OBJECTIVES: 1.1 3.1 4.1 4.3 -
Astrophysical Controls on the Elements of Life, Task 3: Model the Injection of Supernova Material Into Star-Forming Molecular Clouds
The influence of supernova-generated material on the evolution of a solar system depends on the effectiveness with which supernova ejecta can enter the molecular clouds from which solar systems are formed. In this task, we are using computational codes to model the injection of supernova-generated material.
ROADMAP OBJECTIVES: 1.1 3.1 -
Analytical and Theoretical Studies on Origin of Earth’s Oceans and Atmosphere
Origin of Earth’s oceans and atmosphere is an outstanding problem in Earth science. Given the importance of the oceans and atmosphere to Earth’s habitability, it is a critical question for astrobiology as well. Did these features of our planet, so critical for life, originate by regular processes that are likely to be duplicated frequently in other stellar systems, or was there a large element of chance involved? We are approaching this problem by investigating the occurrence of water in the interstellar medium, in the early solar system, and in the deep Earth, using a variety of chemical and isotopic techniques to characterize Earth’s water and to identify the processes that brought it here.
ROADMAP OBJECTIVES: 1.1 3.1 3.2 -
Task 1.2 Interaction of Methane/ethane With Water Ice
The degree of mixing on the Titan surface between liquid hydrocarbons and the icy water surface establishes a potential for reactions that could form prebiotic compounds.
ROADMAP OBJECTIVES: 1.1 2.2 3.1 3.2 3.3 -
Project 3: Pathways for Exogenous Organic Matter to the Early Earth and Mars
Comets are rich in ices and organic molecules and were almost certainly important sources of biogenic elements to early Earth and Mars. However, because of their relatively high encounter speeds (averaging some 50 km/s), comets may be relatively inefficient sources of organic compounds to these planets. In contrast asteroids, although less rich in organics, may have been more important because their much lower encounter speeds (15 – 20 km/s) allow significant quantities of unaltered material to reach the surfaces of the terrestrial planets. A major question we propose to investigate is the relative contributions of the thermally-altered asteroidal organics versus relatively pristine cometary organics to early Earth and Mars.
ROADMAP OBJECTIVES: 1.1 3.1 -
Task 2.1.2 Atmospheric State and Dynamics
An understanding of the structure of the Titan atmosphere provides the context for the formation of complex organic compounds in the atmosphere.
ROADMAP OBJECTIVES: 1.1 2.2 3.1 3.2 3.3 -
Water Delivery to the Surface of Icy Satellites
Oceans below the icy surface of the moons of Saturn and Jupiter may be habitable. Sampling this ocean directly is difficult. This ocean water may, however, erupt onto the surface of these moons and there are active and fossil features that suggest this is possible. We show, however, that cracks are unlikely to penetrate all the way through the ice shell. We also develop models for the coupled orbital and interior evolution of icy satellites.
ROADMAP OBJECTIVES: 1.1 2.2 -
Detectability of Biosignatures
This goal of this project is to study our ability to remotely detect life on planets. Primarily, this applies to extrasolar planets – those that exist outside our solar system. The way we will search for life on these planets is by attempting to detect gases produced by life. For example, we could detect the life on modern-day Earth if we detected gases the presence of molecular oxygen (O2, the gas we breathe that is produced by plants and bacteria) and methane (CH4, which is produced by bacteria). These two gases can co-exist only with production rates so high that they are unsustainable without the presence of life on the planet.
ROADMAP OBJECTIVES: 1.1 1.2 4.1 6.2 -
Project 3: The Origin, Evolution, and Volatile Inventories of Terrestrial Planets
The origin and Sustenance of life on Earth strongly depends on the fact that volatile elements H-C-O-N where retained in sufficient abundance to sustain an ocean-atmosphere. The research in this project involves studies of how terrestrial planets form, why differences exist among the terrestrial planets, how volatiles behave deep within the Earth, and how volatiles and life influence the large and small scale composition of the near surface Earth.
ROADMAP OBJECTIVES: 1.1 3.1 4.1 -
Astrophysical Controls on the Elements of Life, Task 4: Model the Injection of Supernova Material Into Protoplanetary Disks
Supernova-generated material can affect the evolution of a solar system when supernova ejecta enter protoplanetary disks. We are particularly interested in the injection of 26Al, a short-lived radioactive isotope that can affect the delivery of water to Earth-like planets when they are formed. In this task, we are conducting numerical calculations to model such injections in our Solar System, and to understand the consequences for oxygen isotope compositions that can be measured in meteorites.
ROADMAP OBJECTIVES: 1.1 3.1 -
Bioastronomy 2007 Meeting Proceedings
The 9th International Bioastronomy coneference: Molecules, Microbes and Extraterrestrial Life was organized by Commission 51 (Bioastronomy) of the International Astronomical Union, and by the UH NASA Astrobiology team. The meeting was held in San Juan, Puerto Rico from 16-20 July 2007. During the reporting period the Proceedings were finalized and will have a publication date of 2009.
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 -
Astrophysical Controls on the Elements of Life, Task 5: Model the Variability of Elemental Ratios Within Clusters
This task involves a comprehensive study of the chemical evolution of star forming regions arising from stellar processes, and its astrobiological implications. Our approach starts from the point of star formation and models the subsequent production, dissemination, and accretion of 92 chemical elements, with a special focus on bioessential elements and short-lived radionucides. Our goal is to capture the full evolution of over which molecular clouds – the primary units of star-forming gas – are converted into open clusters – the primary units of formed stars. We will then be able to determine the probability distribution of all elements that are important in the formation of terrestrial planets and life.
ROADMAP OBJECTIVES: 1.1 3.1 -
Project 5: Vistas of Early Mars: In Preparation for Sample Return
To understand the history of life in the solar system requires knowledge of how hydrous minerals form on planetary surfaces, and the role these minerals play in the development of potential life forms. One hydrous mineral found on Earth and inferred from in situ measurements on Mars, is the mineral Jarosite, KFe3(SO4)2(OH)6. We are investigating whether radiometric ages, specifically 40Ar/39Ar ages on jarosite can be interpreted to accurately record climate change events on Mars. This project not only requires understanding the conditions required for jarosite formation and preservation on planetary surfaces, but also assessing under what conditions its “radiometric clock” can be reset (e.g., during changes in environmental conditions such as temperature). By studying jarosites formed by a variety of processes on Earth, we will be prepared to analyze and properly interpret ages measured from jarosite obtained from future Mars sample return missions.
ROADMAP OBJECTIVES: 1.1 2.1 7.1 -
CASS Planning
The computational astrobiology summer school (CASS) is a two week program, followed by a semester of mentored independent work, which has the following goals:
- To introduce computer science and engineering (CS&E) graduate students to the field of astrobiology, – To introduce astrobiologists to the tools and techniques that current methods in CS&E can provide, and – To encourage interdisciplinary projects that will result in advances in astrobiology.
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 -
Task 2.1.3 Aerosol Nucleation and Growth
Organic macromolecular aerosols in the Titan atmosphere may contribute to the orange haze seen in the visible spectrum and can serve as the initial stage of prebiotic chemistry on Titan.
ROADMAP OBJECTIVES: 1.1 2.2 3.1 3.2 3.3 -
Characterizing Formation Pathways for 1st Generation Ices
Molecular chemistry can provide insight into the physical processes at the earliest stages of star birth, when molecular cloud cores collapse to form protostellar condensations. Dust particles in the dense clouds accrete molecules from the gas, resulting in the growth of ice mantles that eventually get transported into the protostellar environment. It is here, that the warm and dense environments of star forming regions promote a rich chemistry that creates complex prebiotic compounds and a small fraction of this material ends up as planets. Understanding the dominant chemical pathways and the composition of the first ice mantles formed in starless molecular
clouds allows to better interpret the physical effects of star formation (i.e., temperature, radiation, etc.) on molecular cloud material.ROADMAP OBJECTIVES: 1.1 3.1 -
Task 2.2.1 Characterization of Aerosol Nucleation and Growth
Aerosol nucleation in the Titan atmosphere may form the orange material seen in visible images.
ROADMAP OBJECTIVES: 1.1 2.2 3.1 3.2 3.3 -
Project 6: The Environment of the Early Earth
Our project entitled “Environment of the Early Earth” involves the development of capabilities that will allow scientists to obtain information about the conditions on early Earth (3.0 to 4.5 billion years ago) by performing chemical analyses of crystals (minerals) that have survived since that time. When they grow, minerals incorporate trace concentrations of ions and gaseous molecules from the local environment. We are conducting experiments to calibrate the uptake of these “impurities” that we hope will serve as indicators of temperature, moisture, oxidation state and atmosphere composition. To date, our focus has been mainly on zircon (ZrSiO4), but we have recently turned our attention to quartz as well.
ROADMAP OBJECTIVES: 1.1 4.1 4.3 -
Astrophysical Controls on the Elements of Life, Task 6: Determine Which Elemental or Isotopic Ratios Correlate With Key Elements
In our “follow the elements” strategy we work to refine searches for planetary systems likely to host life by identifying systems with favorable elemental compositions. Because some relevant elements or isotopes (for example 26Al) are difficult or impossible to observe due to low abundances or short lifetimes, we wish to find easily observable indicators of their presence. In most cases this involves identifying elements or isotopes that are either produced primarily by the same process as the isotope of interest or produced in unique ratios to other isotopes by that process. This requires simulating the synthesis of isotopes in stars and supernovae and their ejection into space and incorporation into forming planetary systems.
ROADMAP OBJECTIVES: 1.1 3.1 -
Hydrodynamic Escape From Planetary Atmospheres
We use computer models to simulate the behavior of the upper atmospheres of different planets (Earth, Venus, Mars, Earth-like exoplanets, etc.) during their early evolutionary stages. Young stars produce more flares and other stellar activity than older stars, and the young Sun emitted a greater amount of energetic photons than it does today, which heated the upper atmospheres of the planets. This atmospheric heating led to fast atmosphere escape, which probably controlled the atmospheric composition of early planets. The atmospheric composition on early Earth provides critical constraints on the origin and early evolution of life on this planet. The atmospheric composition of other planets provide important constraints on their habitability.
ROADMAP OBJECTIVES: 1.1 2.1 3.1 -
Modelling Planetary Albedo
What kind of environments could provide opportunities for life in general and for the advent of complex life specifically to emerge? If there were complex life present, what features would it produce? Could we remotely characterize such habitats and the features of complex life on extrasolar planets light-years away with current and future NASA missions?
These are the three main questions we work on in this part of the project.ROADMAP OBJECTIVES: 1.1 1.2 4.1 4.2 6.2 7.2 -
Astrophysical Controls on the Elements of Life, Task 7: Update Catalog of Elemental Ratios in Nearby Stars
We are making 3D maps of the elements in stars within 1000 light-years of the Sun. When completed, these maps will be useful for discovering whether there are neighborhoods or streams of stars more favorable to Earth-like planets and life as we know it.
ROADMAP OBJECTIVES: 1.1 7.2 -
Limits of Habitability
The study of planetary habitability necessitates an interdisciplinary approach. The factors that can affect the habitability of planetary environments are numerous, and the disciplines that can contribute to their investigation and interpretation include, physics, chemistry, geology, biology, and astronomy to name a few.
ROADMAP OBJECTIVES: 1.1 1.2 2.1 4.3 6.2 -
Task 2.2.2.1 Ultraviolet/infrared Spectroscopy of Ice Films
Condensed phase chemistry in organic aerosols can produce large organic macromolecules.
ROADMAP OBJECTIVES: 1.1 2.2 3.1 3.2 3.3 -
Planetary Surface and Interior Models and SuperEarths
In this project, we model the processes that continually reshape the interiors and the surfaces of terrestrial (rocky) planets. The models we develop and use give us insight into how these processes (e.g. weathering, volcanism, and plate tectonics) affect a planet’s habitability as the planet evolves. In addition to Earth- and Mars-like planets, we now seek to model two sorts of planets not observed in our Solar System: 1) “super-Earths” (rocky planets up to 10 times as massive as Earth) and 2) planets so close to their star that the tides actually heat the interior of the planet.
ROADMAP OBJECTIVES: 1.1 1.2 4.1 5.2 6.1 -
Task 2.2.2.3 Aerosol Photoprocessing and Analysis
Organic aerosols produced in the laboratory can be photoprocessed to simulate actual Titan tholin-producing chemistry.
ROADMAP OBJECTIVES: 1.1 2.2 3.1 3.2 3.3 -
Planet Formation and Dynamical Modeling
We examine how various formation processes may impact the potential development of an habitable world, and how subsequent orbital evolution can affect habitability. We explore these phenomena through numerical simulations that allow us to determine the compositions, orbits, and sometimes the internal properties of terrestrial in the Solar System and beyond.
ROADMAP OBJECTIVES: 1.1 3.1 4.3 -
Fingerprinting Late Additions to the Earth and Moon via the Study of Highly Siderophile Elements in Lunar Impact Melt Rocks
Lunar impact melt rocks have been examined for absolute and relative abundances of the highly siderophile elements. This suite of iron-loving elements can potentially be used to fingerprint the large impactors that struck the Earth and Moon during late stages of bombardment. Results for a variety of Apollo and meteoritic impact melt rocks suggest that some impactors were similar to chondritic meteorites but others were not, suggesting an origin via a type of impactor that is no longer sampled by the Earth. Synthesis of these data, as well as data for terrestrial and martian mantle suggests that late accretion was involved in the establishment of the abundances of these elements in their planetary mantles, but could not have been the only process. Pristine lunar crust has very low abundances of all HSE and cannot account for any of the inter-element variations that have been recorded in some lunar impact melt rocks.
ROADMAP OBJECTIVES: 1.1 -
Habitability of Water-Rich Environments, Task 2: Model the Dynamics of Icy Mantles
A major aim of future missions to Jupiter’s moon Europa will be to determine whether or not a subsurface ocean exists beneath the icy surface, and assess its habitability. Such investigations require that we understand how features visible at the surface are related to the ocean that may lie below. A major process governing this interaction is convection within ice. To this end, we are developing a new model of Europa ice convection.
ROADMAP OBJECTIVES: 1.1 2.2 -
Task 3.1 Reactions of Organics With Ices and Mineral Grains
The formation of prebiotic chemical compounds on the Titan surface may be catalyzed by the presence of mineral grains.
ROADMAP OBJECTIVES: 1.1 2.2 3.1 3.2 3.3 -
Habitability of Water-Rich Environments, Task 3: Evaluate the Habitability of Europa’s Subsurface Ocean
We are assessing the habitability of Europa’s ocean by integrating geologic mapping of the Europa surface with geodynamic models of ice convection and geochemical models of ocean and ice composition.
ROADMAP OBJECTIVES: 1.1 2.2 -
Task 3.3 Solubility of Organics in Methane
Liquid methane can serve as a solvent medium in which organic chemistry may occur in sites on the Titan surface.
ROADMAP OBJECTIVES: 1.1 2.2 3.1 3.2 3.3 -
Postdoctoral Fellow Report: Mark Claire
I am interested in how biological gases affect the atmosphere of Earth (and possibly other planets.) Specifically, I use computer models to investigate how biogenic sulfur gases might build up in a planetary atmosphere, and if this would lead to observable traces in Earth’s rock record or in the atmospheres of planets around other stars. I’m also working on how anaerobic oxidizers of methane affected the rise of oxygen on Earth, and if evolutionary changes in nitrogen-using bacteria may have changed global N2 levels and planetary climate.
ROADMAP OBJECTIVES: 1.1 1.2 4.1 7.2 -
The Commonality of Life in the Universe
Is life a common outcome of physical and chemical processes in the universe? Around other stars, Titan-like environments are key astrobiology targets.
ROADMAP OBJECTIVES: 1.1 2.2 3.1 3.2 3.3 -
Origin and Evolution of Organics in Planetary Systems
The central goal of the Blake group effort in the NASA GSFC Astrobiology node (Origin and Evolution of Organics in Planetary Systems (Mike Mumma, P.I.) is to determine whether complex organics such as those seen in meteorites are detectable in the circumstellar accretion disks that encircle young stars and in the comae of comets. Our program has both observational and laboratory components. We use state-of-the-art telescopes from microwave to optical frequencies, and we have developed novel high frequency and temporal resolution instruments that seek to utilize the unique properties of the terahertz (THz) modes of complex organics. The astronomical searches for such modes will begin with Herschel PACS and HIFI observations in early 2010, and will continue with SOFIA and ALMA studies as these observatories become operational in CY2011 and CY2012. The overall suite of laboratory and observational research promises to revolution our understanding of prebiotic chemistry in both our own and other solar systems.
ROADMAP OBJECTIVES: 1.1 1.2 3.1 -
Stellar Effects on Planetary Habitability
Habitable environments are most likely to exist in close proximity to a star, and hence a detailed and comprehensive understanding of the effect of the star on planetary habitability is crucial in the pursuit of an inhabited world. We model how stars with different masses, temperatures and flare activity affect the habitability of planets. We also address the effect that tides between a star and a planet have on planetary habitability, including the power to turn potentially habitable planets like Earth into extremely volcanically active bodies like Io.
ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 4.1 4.3 5.3 6.1 7.2 -
D/H Measurements in Samples From Mantle Hotspots
The origin of Earth’s water is an open question. We are trying to constrain the origin of Earth’s water by measuring the D/H ratios of glass inclusions inside olivine grains from lavas erupted at the Hawaiian and Icelandic hot spots. The hope is that these glass inclusions retain hydrogen from the deep mantle of the Earth, hydrogen that may preserve the original hydrogen isotopic composition of the Earth.
ROADMAP OBJECTIVES: 1.1 -
Understanding Past Earth Environments
This project examines the evolution of the Earth over time. This year we examined and expanded the geological record of Earth’s history, and ran models to help interpret those data. Models were also used to simulate what the early Earth would look like if viewed remotely through a telescope similar to NASA’s Terrestrial Planet Finder mission concept. We focused our efforts on the Earth as it existed in prior to and during the rise of atmospheric oxygen 2.4 billion years ago, as this was one of the most dramatic and important events in the evolution of the Earth and its inhabitants.
ROADMAP OBJECTIVES: 1.1 1.2 2.1 4.1 4.2 4.3 5.1 5.2 5.3 6.1 -
Formation of Carbon and Nitrogen-Rich Organics in Solar System Ices
carbon and nitrogen-rich organics are essential to life as we know it, but how readily available were they on the primordial earth? clues about the composition of primordial material thar could be present come from irradiation experiments on the precursors already identified on interstellar ices
ROADMAP OBJECTIVES: 1.1 2.2 3.1 3.2 -
Understanding the Early Mars Environment
The surface of Mars today is a cold dry desert on which liquid water cannot exist. Evidence from rovers and orbiters indicate that liquid water may have existed on the surface of Mars in the distant past. This project aims to understand how it could have been warm enough for liquid water by creating computer models of the ancient Mars surface, atmosphere, and climate, and comparing the results with the available data. In a nutshell, we are trying to warm up a computer version of Mars, which is not as easy as it sounds.
ROADMAP OBJECTIVES: 1.1 2.1 -
VPL Databases, Model Interfaces and the Community Tool
The Virtual Planetary Laboratory develops modeling tools and provides a collaborative framework for scientists from many disciplines to coordinate research on the environments of extrasolar planets. As part of this framework, the VPL acts as a central repository for planetary models and the inputs required to generate those results. Developing a comprehensive storehouse of input data for computer simulations is key to successful collaboration and comparison of the models. As part of the on-going VPL Community Tools, we have are developing a comprehensive database of molecular, stellar, pigment, and mineral spectra useful in developing extrasolar planet climate models and interpreting the results of NASAs current and future planet-finding missions. The result, called the Virtual Planetary Spectral Library, will provide a common source of input data for modelers and a single source of comparison data for observers.
ROADMAP OBJECTIVES: 1.1 1.2 -
Formation of Higher Carbon Oxides in CO2 Rich Solar System Ices
The interstellar medium contains large dark cold clouds which are full of sub-micrometer interstellar grains. These icy grains are found to contain large amounts of both carbon monoxide and carbon dioxide, however only carbon monoxide is found to be abundant in the gas phase. It is therefore likely that the production of carbon dioxide occurs through the processing of condensed carbon monoxide with irradiation from high energy cosmic rays. It is also likely that more exotic carbon oxides can be produced in this manner, a number of which have been detected for the first time as part of our studies.
ROADMAP OBJECTIVES: 1.1 3.1 -
Giant Planet Formation (Late Stage of the Formation of Jupiter)
Measurements of the abundance of elements in Jupiter’s atmosphere have indicated that high-density materials are several times more abundant in Jupiter’s envelope than in the Sun. To understand the reason for this anomaly, we have started a project on the interactions of planetesimals with Jupiter’s gaseous envelope at the last stage of the formation of this planet.
Results indicate that the deposition of sublimated materials from planetesimals due to gas drag can in crease the metalicity giant planets.ROADMAP OBJECTIVES: 1.1 -
Hydrogen in Nominally Anhydrous Minerals
The amount of water in the Earth’s interior is not known. Experiments have shown that at high pressure, the high-pressure forms of the minerals that make up the Earth’s mantle can contain significant hydrogen substituting for magnesium. We are carrying out a series of experiments to determine how much hydrogen (=water) can be contained in these high-pressure minerals. Mineral samples produced at mantle pressures in the presence of water are being measured using the Cameca ims 1280 ion microprobe at the Unversity of Hawaii to determine the maximum amount of water that each mineral can hold at high pressure, providing a constraint on the possible water content of the mantle.
ROADMAP OBJECTIVES: 1.1 -
Irradiation of Lunar Samples
We are irradiating silicate samples with 1 keV energetic protons (H+) to simulate weathering of silicate rocks on the moon from the solar wind. Here, the goal is to demonstrate the production of water through interaction of the impinging particles with oxygen atoms within the silicate material. This should help explain the recent discoveries from the Indian Chaandrayan-1 spacecraft mission which recently discovered water within the upper layers of the surface.
ROADMAP OBJECTIVES: 1.1 -
Keck Astrochemistry Laboratory
The overall goal of this project is to comprehend the chemical evolution of the Solar System. This will be achieved through an understanding of the formation of carbon-, hydrogen-, oxygen-, and nitrogen-bearing (CHON) molecules in ices of Kuiper Belt Objects (KBOs) by reproducing the space environment in a specially designed experimental setup. KBOs are small planetary bodies orbiting the sun beyond the planet Neptune, which are considered as the most primitive objects in the Solar System. A study of KBOs is important because they resemble natural ‘time capsules’ at a frozen stage before life developed on Earth. Our methodology is based on a comparison of the molecules formed in the experiments with the current composition of KBOs; such approach provides an exceptional potential to reconstruct the composition of icy Solar System bodies at the time of their formation billions of years ago. The significance of this project is that our studies elucidate the origin of biologically relevant molecules and help unravel the chemical evolution of the Solar System. Since KBOs are believed to be the main reservoir of short-period comets, which are considered as ‘delivery systems’ of biologically important molecules to the early Earth, our project also brings us closer to the understanding of how life might have emerged on Earth.
ROADMAP OBJECTIVES: 1.1 2.1 2.2 3.1 3.2 -
Light Curve of Main Belt Comet 176P/LINEAR
Comet 176P/Linear belongs to the new class of main belt comets (MBCs) which show both, asteroid and comet like behavior. As these solar system bodies reside in the asteroid belt between Mars and Jupiter, they are easier to reach for a spacecraft compared to comets in the Oort cloud or the Kuiper belt. We are proposing a NASA Discovery-Class mission to such a main belt comet. Currently only four MBSs are known and it is crucial that we learn as much as possible about their physical properties. The aim of this project is to obtain a rotational light curve from recent observations with the UH2.2m telescope on Mauna Kea. The light curve will allow us to determine the how fast the comet’s nucleus is rotating.
ROADMAP OBJECTIVES: 1.1 3.1 -
Main Belt Comet Origin, Formation and Activation
Main Belt Comets are a new class of objects that have recently been detected in the asteroid belt. These objects carry sub-surface water ice that may have played an important role in the delivery of water to the Earth. This project aims to understand the origin of MBCs, their contribution to Earth’s water budget, and the regions in the asteroid belt where many of these bodies can be found.
ROADMAP OBJECTIVES: 1.1 -
Main Belt Comet P/2008 R1 Garradd Characterization
We identified P/2008 R1 as a main-belt comet (previously mis-classified as an ordinary Jupiter-family comet) and mounted an observational program to assess its physical properties, and a dynamical campaign to understand its orbit.
ROADMAP OBJECTIVES: 1.1 2.2 3.1 -
Mars Bulk Composition
The bulk composition of Mars, including its total inventory of water, is central to understanding how planets form and to fully understanding the role of water in Martian geological evolution.
ROADMAP OBJECTIVES: 1.1 2.1 -
MBC Mission Development
The distribution of water and volatiles in our solar system may be a primary determinant of solar system habitability. Main Belt Comets (MBCs), a newly discovered class of volatile-containing objects in the asteroid belt, present a sub-class of particular significance both to the water history, and to the history of other important volatiles in our solar system. As comets in near-circular orbits within the asteroid belt, these objects may harbor water condensed and frozen out from the primordial ‘snow line’ of the young solar system. Studying MBC water and volatile inventory will advance our understanding of both the origin of Earth’s ocean and of volatile inventories throughout the Solar System. The UH NAI team is developing a concept for a Discovery class mission to study the Main Belt Comets.
ROADMAP OBJECTIVES: 1.1 2.2 3.1 -
Origin of the Parent Bodies of Iron Meteorites and Constraint on Giant Planet Formation
Understanding the origin of the parent bodies of iron meteorites is essential to the theories of planet formation. These objects are formed less then two million years after the formation of the first bodies in the solar system. As a result understanding their formation may reveal clues to the time of the formation of giant planet. We are continuing our project on this topic, and are studying the effects of the growth of giant planets on the dynamics of planetesimals, and their chosmochemical properties.
ROADMAP OBJECTIVES: 1.1 -
PanSTARRS MBC Stamp Server and Detection Limits
We have been developing the architecture to search for main belt comets (MBCs) in the upcoming Pan-STARRS1 all sky survey. MBCs are an important new reservoir of water in the inner solar system, and we hope to be detecting a steady stream of them in PS1 beginning in late 2009 or early 2010.
ROADMAP OBJECTIVES: 1.1 2.2 6.2 -
Quantification of the Disciplinary Roots of Astrobiology
The questions of astrobiology span many scientific fields. This project analyzes databases of scientific literature to determine and quantify the diverse disciplinary roots of astrobiology. This is one component of a wider study to build a map of relationships between the constituent fields of astrobiology, so relevant knowledge in diverse fields can be most efficiently inform the study of life in the universe.
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 -
Terrestrial and Habitable Planet Formation in Binary Stars
We are studying the formation of Earth-like/habitable planets in binary star systems, in particular those that host a giant planet. We are simulating the formation of these bodies for different distribution of water in a circumstellar disk. With more than 50% of stars in binary systems, it is quite possible that Kepler space telescope may soon find many of such binary-planetary systems.
ROADMAP OBJECTIVES: 1.1 -
Ultra-Violet Processing of Ices in the Rosette Molecular Cloud
Ices and organics in the molecular clouds are subjected to a plethora of harsh conditions such as thermal, ultraviolet- (UV), and particle-irradiation that destroy, sputter or modify the material. As a result, it is likely that the molecular compounds found in the initial cloud and those observed in circumstellar disks may not, at first glance, be very similar but instead are linked via complex chemical networks. the Sun formed in a high mass star-forming cloud where at least one, and most likely many, supernova events occurred, resulting in intense UV radiation throughout the cloud complex. The Rosette molecular cloud provides the perfect laboratory analog for the early solar nebula molecular cloud. This project is a comparative study of the UV processing of the ices toward several embedded stellar clusters in the Rosette molecular cloud.
ROADMAP OBJECTIVES: 1.1 3.1 -
VYSOS Construction
The VYSOS project aims at surveying all the major star forming regions
all across the entire northern and southern sky for variable young
stars. Two small survey telescopes have been purchased and provide
large area shallow observations, and two larger telescopes allow
deeper more detailed observations. All observations are done
robotically.ROADMAP OBJECTIVES: 1.1 1.2 2.2