"If the moon were smaller than it is, would total eclipses of the sun be impossible?"
Welcome to the NAI Newsletter! The Newsletter is a compendium of announcements, events, updates, and news items related to the NAI and its research. If you have news items or suggestions you can send them to the editor, Marco Boldt at: Marco.Boldt@nasa.gov.
Newsletter for November 4, 2009
- 11/30 NAI Director's Seminar: Andrew Pohorille, "Is Water Necessary for Life?"
- UH Team Member Tobias Owen Receives 2009 Gerard P. Kuiper Prize in Planetary Sciences
- 11/10 University of Washington Astrobiology Seminar: Kevin Hand, "Joule Heating of the South Polar Terrain on Enceladus"
- Oxygen Production in Earth's Early Oceans Predates the Great Oxidation Event
- 'Ultra-Primitive' Particles Found in Comet Dust
- Ribosomes as Ancient Molecular Fossils
- Astrobiology Graduate Conference (AbGradCon) 2010
- NASA Earth and Space Science Fellowship (NESSF) Program
- Two Post-doc Positions in Astrobiology Available at JPL, Caltech
- Teachers from Around the World Examine Life in Extreme Environments
- Astrobiology Teachers Academy
- Ice in the Solar System...in Your Classroom
11/30 NAI Director's Seminar: Andrew Pohorille, "Is Water Necessary for Life?"
Date/Time: Monday, November 30, 2009 11:00AM Pacific
Speaker: Andrew Pohorille (NASA Ames Research Center)
Abstract:
“Follow the water” is the canonical strategy in searching for life in the universe. Conventionally, discussion of this topic is focused on the ability of a solvent to support organic chemistry sufficiently rich to seed life. Although this is a necessary condition for the emergence of life it is far from being sufficient. Perhaps more importantly, solvent must promote self-organization of organic matter into functional structures capable of responding to environmental changes. In biology, they are mostly based on non-covalent interactions (interactions that do not involve making or breaking chemical bonds), strength of which must be properly tuned. If non-covalent interactions were too weak, the system would exhibit undesired, uncontrolled response to natural fluctuations of physical and chemical parameters. If they were too strong kinetics of biological processes would be slow and energetics costly.
Non-covalent interactions are very strongly mediated by the solvent. In particular, potential solvents for life must be characterized by a high dielectric constant to ensure solubility of polar species and sufficient flexibility of biological structures stabilized by electrostatic interactions. Among these solvents, water exhibits a remarkable trait that it also promotes solvophobic (hydrophobic) interactions between non-polar species, typically manifested by a tendency of these species to aggregate and minimize their contacts with the aqueous solvent. Hydrophobic interactions are responsible, at least in part, for many self-organization phenomena in biological systems, such as the formation of cellular boundary structures or protein folding. Strengths of electrostatic and hydrophobic interactions are similar and can be balanced over a wide range of temperatures, which considerably increases the repertoire of interactions that can be used to modulate biological functions.
Some properties of water, e.g. its chemical activity against polymerization reactions, are considered as unfavorable to life. In actuality, this might be a favorable trait because life requires a balance between constructive and destructive processes. For example, molecules synthesized in response to specific conditions must be degraded once these conditions change. Otherwise regulation of biological processes would be virtually impossible.
Water might not be the only liquid with favorable properties for supporting life. One example is formamide, which might be present elsewhere in the universe in sufficient quantities to warrant interest as a potential alternative to water for the origin of life. However, further studies on physical, chemical and biological properties of non-aqueous solutions are needed to draw firmer conclusions on this subject.
For more information and participation instructions: http://astrobiology.nasa.gov/nai/seminars/detail/161
UH Team Member Tobias Owen Receives 2009 Gerard P. Kuiper Prize in Planetary Sciences
The NAI extends its congratulations to University of Hawaii team member Tobias Owen for receiving the 2009 Gerard P. Kuiper Prize. The Gerard P. Kuiper Prize was established by the Division for Planetary Sciences (DPS) to recognize and honor outstanding contributors to planetary science. It is to be awarded to scientists whose achievements have most advanced our understanding of the planetary system.
For more information: http://dps.aas.org/prizes/kuiper
11/10 University of Washington Astrobiology Seminar: Kevin Hand, "Joule Heating of the South Polar Terrain on Enceladus"
Date/Time: Tuesday November 10, 2009 2:30PM Pacific
Speaker: Kevin Hand (Jet Propulsion Laboratory)
Abstract:
The plumes and observed heat flux in the South Polar Terrain of Enceladus remain a considerable mystery. We report that Joule heating in Enceladus – resulting from the interaction of Enceladus with Saturn's magnetic field – may account for several, to a few tens of megawatts of power across the observed "tiger stripe" fractures. Electric currents passing through subsurface channels of low salinity and just a few kilometres in depth could supply a source of power to the South Polar Terrain, providing a small but previously unaccounted for contribution to the observed heat flux and plume activity.
For more information and participation instructions: http://astrobiology.nasa.gov/nai/seminars/detail/164
Recently Published Research from the NAI
Oxygen Production in Earth's Early Oceans Predates the Great Oxidation Event
It is widely accepted that around 2.4 billion years ago, the Earth’s atmosphere underwent a dramatic change when oxygen levels rose sharply. Called the “Great Oxidation Event” (GOE), the oxygen spike marks an important milestone in Earth’s history, the transformation from an oxygen-poor atmosphere to an oxygen-rich one paving the way for complex life to develop on the planet.
Two questions that remain unresolved in studies of the early Earth are when oxygen production via photosynthesis got started and when it began to alter the chemistry of Earth’s ocean and atmosphere.
A research team that includes members of NAI’s Arizona State University team corroborates recent evidence that oxygen production began in Earth’s oceans at least 100 million years before the GOE, and goes a step further in demonstrating that even very low concentrations of oxygen can have profound effects on ocean chemistry. Their study is published in the current issue of Science.
To arrive at their results, the researchers analyzed 2.5 billion-year-old black shales from Western Australia, samples provided through the NAI’s Astrobiology Drilling Program. Essentially representing fossilized pieces of the ancient seafloor, the fine layers within the rocks allowed the researchers to page through ocean chemistry’s evolving history.
Specifically, the shales revealed that episodes of hydrogen sulfide accumulation in the oxygen-free deep ocean occurred nearly 100 million years before the GOE and up to 700 million years earlier than such conditions were predicted by past models for the early ocean. Scientists have long believed that the early ocean, for more than half of Earth’s 4.6 billion-year history, was characterized instead by high amounts of dissolved iron under conditions of essentially no oxygen.
Said Timothy Lyons of UC Riverside who led the study, “This is important because oxygen-poor and sulfidic conditions almost certainly impacted the availability of nutrients essential to life, such as nitrogen and trace metals. The evolution of the ocean and atmosphere were in a cause-and-effect balance with the evolution of life.”
'Ultra-Primitive' Particles Found in Comet Dust
Dust samples collected by high-flying aircraft in the upper atmosphere have yielded an unexpectedly rich trove of relicts from the ancient cosmos, report scientists from NAI’s Carnegie Institution of Washington team in Earth and Planetary Science Letters. The stratospheric dust includes minute grains that likely formed inside stars that lived and died long before the birth of our sun, as well as material from molecular clouds in interstellar space. This “ultra-primitive” material likely wafted into the atmosphere after the Earth passed through the trail of an Earth-crossing comet in 2003, giving scientists a rare opportunity to study cometary dust in the laboratory.
At high altitudes, most dust in the atmosphere comes from space, rather than the Earth’s surface. Thousands of tons of interplanetary dust particles (IDPs) enter the atmosphere each year. “We’ve known that many IDPs come from comets, but we’ve never been able to definitively tie a single IDP to a particular comet,” says study coauthor Larry Nittler, of Carnegie’s Department of Terrestrial Magnetism. “The only known cometary samples we’ve studied in the laboratory are those that were returned from comet 81P/Wild 2 by the Stardust mission.” NASA’s Stardust mission collected samples of comet dust, returning to Earth in 2006.
Comets are thought to be repositories of primitive, unaltered matter left over from the formation of the solar system. Material held for eons in cometary ice has largely escaped the heating and chemical processing that has affected other bodies, such as the planets. However, the Wild 2 dust returned by the Stardust mission included more altered material than expected, indicating that not all cometary material is highly primitive.
The IDPs used in the current study were collected by NASA aircraft in April 2003, after the Earth passed through the dust trail of comet Grigg-Skjellerup. The research team, which included Carnegie scientists Nittler, Henner Busemann (now at the University of Manchester, U.K.), Ann Nguyen, George Cody, and seven other colleagues, analyzed a sub-sample of the dust to determine the chemical, isotopic and microstructural composition of its grains.
“What we found is that they are very different from typical IDPs” says Nittler. “They are more primitive, with higher abundances of material whose origin predates the formation of the solar system.” The distinctiveness of the particles, plus the timing of their collection after the Earth’s passing through the comet trail, point to their source being the Grigg-Skjellerup comet.
“This is exciting because it allows us to compare on a microscopic scale in the laboratory dust particles from different comets,” says Nittler. “We can use them as tracers for different processes that occurred in the solar system four-and-a-half billion years ago.”
The biggest surprise for the researchers was the abundance of so-called presolar grains in the dust sample. Presolar grains are tiny dust particles that formed in previous generations of stars and in supernova explosions before the formation of the solar system. Afterwards, they were trapped in our solar system as it was forming and are found today in meteorites and in IDPs. Presolar grains are identified by having extremely unusual isotopic compositions compared to anything else in the solar system. But presolar grains are generally extremely rare, with abundances of just a few parts per million in even the most primitive meteorites, and a few hundred parts per million in IDPs. “In the IDPs associated with comet Grigg-Skjellerup they are up to the percent level,” says Nittler. “This is tens of times higher abundances than we see in other primitive materials.”
Also surprising is the comparison with the samples from Wild 2 collected by the Stardust mission. “Our samples seem to be much more primitive, much less processed, than the samples from Wild 2,” says Nittler, “which might indicate that there is a huge diversity in the degree of processing of materials in different comets.”
Ribosomes as Ancient Molecular Fossils
Members of NAI’s team at Georgia Tech have a new paper in Molecular Biology and Evolution describing an analysis of ribosomal structure and sequence. Their approach chronicles the ribosome’s evolution, effectively interpreting the ribosome as a fossil. Using the highest resolution structures available, of two species that represent disparate regions of the evolutionary tree, they have sectioned the large subunit of each ribosome into concentric shells, like an onion, using the site of peptidyl transfer as the origin. Their results suggest that the structure and interactions of both RNA and protein can be described as changing, in an observable manner, over evolutionary time.
For Students and Young Investigators
Astrobiology Graduate Conference (AbGradCon) 2010
Tällberg, Sweden - June 14-18, 2010.
In 2010, AbGradCon, the foremost astrobiology meeting for early-career researchers, will be held in Europe for the first time in its history. Graduate students and early-career postdocs from all over the world will come together to present their research in a comfortable environment, to learn of the latest developments in astrobiology, to network and to forge new collaborations. The meeting will comprise oral and poster presentations, half-day workshops and a one-day field trip to geologically instructive sites in the astrobiologically interesting Siljan impact crater. Attendees are encouraged from the very wide range of subjects pertinent to astrobiology. Financial assistance will be available to invited attendees.
Further information is available at the conference website: http://www.abgradcon2010.org
NASA Earth and Space Science Fellowship (NESSF) Program
NASA announces a call for graduate fellowship proposals to the NASA Earth and Space Science Fellowship (NESSF) program for the 2010-2011 academic year. This call for fellowship proposals solicits applications from accredited U.S. universities on behalf of individuals pursuing Master of Science (M.Sc.) or Doctoral (Ph.D.) degrees in Earth and space sciences, or related disciplines. The purpose of NESSF is to ensure continued training of a highly qualified workforce in disciplines needed to achieve NASA's scientific goals. Awards resulting from the competitive selection will be made in the form of training grants to the respective universities.
The deadline for NEW applications is February 1, 2010, and the deadline for RENEWAL applications is March 15, 2010.
The NESSF call for proposals and submission instructions are located at the NESSF 09 solicitation index page at http://nspires.nasaprs.com/ - click on "Solicitations" then click on "Open Solicitations" then select the "NESSF 10" announcement. Also refer to "Proposal Submission Instructions" listed under "Other Documents" on the NESSF 10 solicitation index page.
All proposals must be submitted in electronic format only through the NASA NSPIRES system. The advisor has an active role in the submission of the fellowship proposal. To use the NSPIRES system, the advisor, the student, and the university must all register. Extended instructions on how to submit an electronic proposal package are posted on the NESSF 10 solicitation index page listed above. You can register in NSPIRES at http://nspires.nasaprs.com/.
For further information contact Russell Deyoung, Program Administrator for NESSF Earth Science Research, Telephone: (757) 864-1472, E-mail: larc-nessf-Earth@lists.nasa.gov or Dolores Holland, Program Administrator for NESSF Heliophysics Research, Planetary Science Research, and Astrophysics Research, Telephone: (202) 358-0734, E-mail: hq-nessf-Space@nasa.gov.
Two Post-doc Positions in Astrobiology Available at JPL, Caltech
The California Institute of Technology (Caltech) Postdoctoral Scholars Program at the Jet Propulsion Laboratory (JPL) invites applicants to apply for two postdoctoral research positions at JPL in the Planetary Science Section of the Science Division. Each opportunity is supported by a NASA grant to two separate, small, collaborative teams. The successful candidates, while having their own projects, will be expected to work with team members in other institutions.
Topic 1, Mineral biosignatures.
This topic forms part of the work supported by the NASA Astrobiology Institute through its Wisconsin Astrobiology Research Consortium team (U. Wisconsin, JPL and U. Georgia).
The aim of the research is to develop new biosignatures and paleoenvironmental proxies, with a focus on sulfate evaporate minerals. The planned work has two main strands. It will involve comparing the isotopic compositions of minerals formed by microbial oxidation of sulfides and the abiotic equivalents and also to make laboratory simulations of evaporation sequences and to use the isotopic data to constrain amount of water involved and the paleo-atmospheric-humidity. The biosignatures and paleoenvironmental indicators will be tested by application to the Rio Tinto system, Spain.
Topic 2, The Earth's deepest hydrothermal vents.
This research is funded by the NASA program, Astrobiology Science and Technology for Exploring Planets (ASTEP). The work is a collaboration between Woods Hole Oceanographic Institution (WHOI), JPL, the Marine Biological Laboratory (MBL) and Duke University Marine Laboratory (DUML).
We will be using WHOI's new Hybrid-ROV, Nereus, to investigate hydrothermal systems (past and present) along Earth's deepest mid-ocean ridge: the ~110km long ultra-slow spreading Mid-Cayman Spreading Center. Sampling is scheduled for Oct-Nov 2009. The results of the work will be used to plan astrobiological exploration of any planetary body that can host hydrothermal circulation (for example, Jupiter's moon, Europa). The research will involve characterization of minerals and their geochemical and stable isotope compositions to contribute to understanding the present and past energy budgets of the system. The post-doc also will be involved in the application of the integrated results to planning future NASA planetary exploration missions.
The selected candidates will both be guided by the JPL advisor, Dr. Max Coleman, to ensure that the research work will result in publications in the peer-reviewed literature.
Candidates should have a Ph.D. in geochemistry, astrobiology, biogeochemistry, geology, chemistry, environmental science (or other sciences) with a strong background in stable isotope analysis. The appointment is contingent upon evidence of completion of a Ph.D.
For more information: http://postdocs.jpl.nasa.gov/researchapplicants/jobpostings/index.cfm?FuseAction=ShowJobPosting&JobPostingID=179
Teachers from Around the World Examine Life in Extreme Environments
This summer, sixteen teachers from around the world convened with NAI’s team at Montana State University for a week-long class called “Examining Life in Extreme Environments: Insights into Early Earth and Beyond.” Students in the course gained an understanding of the relation of extreme environments to early Earth, learned about the latest research conducted in these areas, and worked on how to teach and discuss these topics within their own classrooms.
Part of the class included a field trip to Yellowstone National Park in which the teachers sampled and characterized extreme environments. Joe Deluca, who teaches in the Netherlands, was amazed by Yellowstone and was most surprised by “how drastically and quickly the changes in microbe gradients were in the thermal features.” Paula Wang, a teacher from Sidwell Friends School in Washington, D.C. called the class “fun, convenient, and practical.”
The class was offered by MSU as part of the Master of Science in Science Education Program (MSSE) and is only one of the many MSSE courses that involve field work in Yellowstone and the surrounding areas. The course provided graduate credit in chemistry and/or biology for professional development purposes. This interdisciplinary course featured NAI scientists John Peters, PI of the NAI MSU team, and John Priscu, professor of Land Resources and Environmental Sciences and member of the NAI Icy Worlds team. More information about MSU’s Astrobiology Biogeocatalysis Research Center can be found at abrc.montana.edu and the MSSE program can be found at montana.edu/msse.
Astrobiology Teachers Academy
NAI’s New York Center for Astrobiology held its first Teachers Academy at RPI on July 13-16, 2009. Nine high school science teachers from four local school districts collaborated with six NAI scientists to learn about topics in astrobiology. The participants represent disciplines across the sciences: biology, chemistry, earth science, forensic science, and physics. The goal of the Academy was to develop a learning module infused with astrobiology and aligned with New York State standards and NASA Astrobiology Science Goals. The teachers used science lectures, existing astrobiology curriculum materials, and consistent interaction with the scientists to develop their learning modules, which ranged in topic from the physiochemical limits to sustainable life, to colors of photosynthetic organisms on exoplanets, to nucleosynthesis of biologically-relevant elements. The teachers are implementing their modules in their classrooms this school year, and the Academy will be featured at the annual regional meeting of the Science Teachers Association of New York State in March, 2010.
Ice in the Solar System...in Your Classroom
Exploring Ice in the Solar System is a series of lessons for K-5 classrooms developed by the NAI Carnegie Institution of Washington Team and the NASA MESSENGER mission. Twelve lessons span topics from ice in everyday life, to exploring ice in the polar regions of Earth, to icy places on Mars and Europa, to life in ice. Each standards-aligned lesson consists of substantive background information, inquiry-based activities, teaching tips, resources, a photo gallery, and strategies for differentiated instruction and evaluation.
For more information: http://urbansciencecorps.org/index.php?contentID=2761
For the Astrobiology Community
Call for Nominations for the 2010 Kavli Prize
The Kavli Prize is a partnership between The Norwegian Academy of Science and Letters, The Kavli Foundation (US) and The Norwegian Ministry of Education and Research.
The Prize was established to:
- Recognise outstanding scientific research
- Honour highly creative scientists
- Promote public understanding of scientists and their work
- Foster international cooperation among scientists
The Kavli Prize is awarded every second year by The Norwegian Academy of Science and Letters at a Ceremony in Oslo, Norway. The Call for Nominations for the 2010 Kavli Prize will be open from September 1 – December 15, 2009.
For more information: http://www.kavliprize.no/artikkel/vis.html?tid=27137
Lunar and Planetary Laboratory (LPL) Faculty Position Openings
Assistant, Associate, OR full Professor
The Department of Planetary Sciences/Lunar and Planetary Laboratory at the University of Arizona expects to fill up to three tenure track faculty positions. Candidates in all areas of planetary science are encouraged to apply. Current faculty and research staff are involved in the scientific exploration of the Solar System including the Sun and heliosphere, comparative planetary studies, exoplanetary systems, origins of planetary systems, and inquiry into the presence of life elsewhere in the cosmos. They employ tools such as theoretical studies and data analysis, laboratory and field investigations, telescopic observations, remote sensing, spacecraft instrumentation, and spacecraft mission development and operations. The faculty, research staff, and graduate student body are drawn from the diverse backgrounds of planetary science, astronomy, chemistry, geology, physics, and engineering. Additional information concerning the Department/Laboratory is available at http://www.lpl.arizona.edu .
Duties and Responsibilities:
Successful candidates will teach at all levels, from freshman through advanced graduate classes. They will establish and maintain a distinguished research program and will supervise graduate students.
Minimum Qualifications:
Ph.D. in a related field. To be considered for an appointment above the rank of Assistant Professor, candidates must have an internationally recognized record of distinguished scientific achievement, leadership, and teaching ability in the planetary sciences. To be considered for appointment at the rank of Assistant Professor, candidates must demonstrate clear promise of such achievement. Review of materials will begin immediately (October 2009) and will continue until positions are filled. Full position details and online application are available at http://www.hr.arizona.edu; reference job #43641. Applicants MUST apply through the above URL, but should also send an original set of application materials (including a curriculum vitae, letter of interest, and statement of research and teaching interests) to: Professor Michael J. Drake, Head and Director, Department of Planetary Sciences/Lunar and Planetary Laboratory, 1629 E. University Blvd., The University of Arizona, Tucson, AZ 85721-0092.
See full page flyer at http://www.lpi.usra.edu/features/positions/lpl/fllyer.pdf
