Jupiter, long settled in its position as the fifth planet from our sun, was a rolling stone in its youth. Over the eons, the giant planet roamed toward the center of the solar system and back out again, at one point moving in about as close as Mars is now. The planet's travels profoundly influenced the solar system, changing the nature of the asteroid belt and making Mars smaller than it should have been. These details are based on a new model of the early solar system developed by NAI scientists at the Virtual Planetary Laboratory, the Goddard Center for Astrobiology, and their colleagues. Their paper appears in a recent issue of Nature.

"We refer to Jupiter's path as the Grand Tack, because the big theme in this work is Jupiter migrating toward the sun and then stopping, turning around, and migrating back outward," says the paper's first author, Kevin Walsh of the Southwest Research Institute in Boulder, Colo. "This change in direction is like the course that a sailboat takes when it tacks around a buoy."

According to the new model, Jupiter formed in a region of space about three-and-a-half times as far from the sun as Earth is (3.5 astronomical units). Because a huge amount of gas still swirled around the sun back then, the giant planet got caught in the currents of flowing gas and started to get pulled toward the sun. Jupiter spiraled slowly inward until it settled at a distance of about 1.5 astronomical units--about where Mars is now. (Mars was not there yet.)

For more information: http://astrobiology.nasa.gov/articles/jupiter-s-grand-tack-reshaped-the-solar-system/

Source: NAI newsletter

Posted by Keith Cowing at 8:32 PM | Permalink | Comments (0)

We are pleased to announce the dates for the second workshop on "Titan Through Time: Formation, Evolution and Fate" in 2012, following the very successful first workshop in 2010. The second meeting will have a similar format, with a 2 1/2 science program comprised of themed sessions, and featuring a mixture of invited reviews, and contributed talks and posters.

As in 2010, we welcome scientific reports and attendance from the widest possible cross-section of the scientific community, including both those studying Titan directly, but also those whose research interests have intersections with Titan science in areas such as laboratory chemistry and spectroscopy; modeling of planetary atmospheres, surfaces and interiors; terrestrial analogs and comparative planetology; and the formation and evolution of the solar system.

Further details including the program of invited talks will be publicized in due course. A link to the website (when available) can be booked-marked here: http://www.astro.umd.edu/~nixon/ttt-2012.html

Hope to see you in 2012.

Conor Nixon, Univerity of Maryland
Ralph Lorenz, Johns Hopkins APL
Co-chairs, science program.

Posted by Keith Cowing at 6:31 PM | Permalink | Comments (0)

The Lunar and Planetary Institute (LPI), part of the Universities Space Research Association, invites applications for a postdoctoral fellowship in the petrology of planetary materials.

The successful candidate will work with Dr. Allan Treiman in NASA-funded efforts, focusing on planetary crusts and magmas, and their volatiles constituents; target materials include lunar highlands rocks, Martian meteorites, and terrestrial analogs.  These efforts focus on planetary samples, starting with analyses by optical microscopy and electron microprobe; other instruments are available at nearby Johnson Space Center or with external collaborators.  The candidate will be encouraged to design and conduct their own research in planetary science, propose for external funding, participate in grant review panels and analysis groups, and become involved with spacecraft missions.

The successful candidate will have a recent Ph.D. in petrology or geochemistry; experience with planetary materials is helpful, but not required.  The position would be for two years, with possible extension to a third year.  Review of candidates will begin on November 15, 2011, with a hiring decision as soon as possible thereafter. Further information can be found on our website: http:// www.lpi.usra.edu

The Universities Space Research Association is an Equal Opportunity Employer.

Posted by Keith Cowing at 5:39 PM | Permalink | Comments (0)

Some asteroids may have been like "molecular factories" cranking out life's ingredients and shipping them to Earth via meteorite impacts. Now it appears that at least one asteroid may have been less like a rigid assembly line and more like a flexible diner that doesn't mind making changes to the menu.

Astrobiologists at NAI's Goddard Space Flight Center and Carnegie Institution of Washington teams studying the carbon-rich Tagish Lake meteorite have discovered that different pieces of it have greatly differing amounts of amino acids, the building blocks of proteins and essential ingredients to life as we know it.

In January, 2000, a large meteoroid exploded in the atmosphere over northern British Columbia, Canada, and rained fragments across the frozen surface of Tagish Lake. Because many people witnessed the fireball, pieces were collected within days and kept preserved in their frozen state. This ensured that there was very little contamination from terrestrial life.

"The Tagish Lake meteorite fell on a frozen lake in the middle of winter and was collected in a way to make it the best preserved meteorite in the world," said Dr. Christopher Herd of the University of Alberta, Edmonton, Canada, lead author of a paper about the analysis of the meteorite fragments published June 10 in the journal Science.

"The first Tagish Lake samples -- the ones we used in our study that were collected within days of the fall -- are the closest we have to an asteroid sample return mission in terms of cleanliness," adds Dr. Michael Callahan of NASA's Goddard Space Flight Center in Greenbelt, Md., a co-author on the paper.

Continue reading "Asteroid Served Up "Custom Orders" of Life's Ingredients" »

Posted by Keith Cowing at 12:40 AM | Permalink | Comments (0)

Ancient rocks are shedding new light on the timeline for life's emergence on Earth. The rocks from the Nuvvuagittuq Supracrustal Belt in Quebec, Canada, are believed to be some of the oldest on Earth. They contain carbon-based minerals that had been interpreted as evidence of the Earth's early biosphere, however, new research tells a different story. By applying cutting-edge technology to the rock samples, a team of scientists have revealed that the carbon minerals found in the rocks may be much younger than the rocks themselves.

"The characteristics of the poorly crystalline graphite within the samples are not consistent with the metamorphic history of the rock," said co-author Dominic Papineau in a news release from Boston College. "The carbon in the graphite is not as old as the rock. That can only ring a bell and require us to ask if we need to reconsider earlier studies."

The results were reported in the May 15, 2011 edition of the journal Nature Geoscience. Funding organizations for this work included the NASA Exobiology and Evolutionary Biology Program (Exo/Evo), the NASA Astrobiology Institute (NAI), the W.M. Keck Foundation, the Geophysical Laboratory of the Carnegie Institution of Washington, Carnegie of Canada, the Naval Research Laboratory, the NRC Research Associateship Program, Boston College, and the Fond Quebecois pour la recherche sur la nature et les technologies (FQRNT).

Posted by Keith Cowing at 11:35 AM | Permalink | Comments (0)

Date/Time: Monday, March 28, 2011 11:00AM Pacific
Presenter: George Cody (Carnegie Institution of Washington)

Abstract:

Primitive bodies in the Solar System contain relatively large quantities of refractory organic macromolecular material. A lack of consensus exists as to the ultimate origin of these extraterrestrial organic solids stemming largely from the fact that throughout the Galaxy there exist many regions were extensive organo-synthesis occurs. Origins theories span from the lowest temperatures in the Interstellar Medium up to 1000 K in the inner Solar System. The best constraint on the origin of refractory organic solids is obtained by detailed studies of the organic material directly. Using advanced spectroscopic techniques we have identified a plausible source for these organic solids and show that the organic solids in both comets and carbonaceous chondrites share a common origin. The broader implications of these results, both in terms of our understanding of the early history of primitive Solar System objects and the origin of life on Earth, will be discussed.

For more information and participation instructions: http://astrobiology.nasa.gov/nai/seminars/detail/190

Source: NAI Newsletter

Posted by Keith Cowing at 10:28 PM | Permalink | Comments (0)

A new study in a recent issue of Science from NAI's NASA Goddard Space Flight Center Team and their colleagues looks at late accretion in the formation of the Earth, Moon, and Mars. Puzzled by the presence of highly siderophile elements (HSUs) in the terrestrial, lunar, and martian mantles, they show that the bombardment by leftover planetesimal populations dominated by massive projectiles can explain these additions. Their inferred size distribution matches those derived from the inner asteroid belt, ancient martian impact basins, and planetary accretion models. The largest late terrestrial impactors, at 2500 to 3000 kilometers in diameter, potentially modified Earth's obliquity by ~10*, whereas those for the Moon, at ~250 to 300 kilometers, may have delivered water to its mantle. [Source: NAI Newsletter]

Posted by Keith Cowing at 12:02 AM | Permalink | Comments (0)

Exclusive Interview: Discoverer of Arsenic Bacteria, in the Eye of the Storm, Science Now

"Q: So, NASA approached you about doing a press conference, and you thought that was a good idea? F.W.-S.: I wouldn't say I thought it was a good or bad idea. I'd never been to a press conference, but it made good sense to me that my mom should know what I'd been up to, and I love teaching. So, it made sense to me at that level, in terms of, again, bringing what we did to the public. But we weren't clearly prepared, in terms of understanding how it might be, again, with the new types of media that are really rather amazing, what was exactly going to happen."

Earlier posts

Posted by Keith Cowing at 9:59 AM | Permalink | Comments (0)

The 2011 Gordon Research Conference on the Origins of Solar Systems will take place at Mt. Holyoke College in South Hadley, MA 17-22 July 2011. This unique interdisciplinary meeting includes astronomers and astrophysicists interested in star and planet formation, planetary scientists and cosmochemists interested in the early history, structure, and evolution of the Solar System, as well as scientists in related disciplines. By bringing together this mix of expertise the conference attempts to address fundamental questions that are not tractable within the confines of just one discipline. Our goal is to understand whether planetary systems like our own, and the potential for habitability that they represent are the exception or the rule in the Milky Way galaxy.

The focus of the 2011 meeting (the 11th since this series began twenty years ago) will be "Composition of Forming Planets: A Tool to Understand Processes". Topics covered will include: 1) the initial conditions for planet formation in circumstellar disks, including estimates of solar nebula composition from the Genesis mission; 2) the evolution of the physical structure of the gas and dust from which planets form; 3) progress in our theoretical understanding of the major physical processes that control planet formation; 4) the interplay between disk dynamics and disk chemistry in determining the composition of forming planets including new results from the Herschel Space Telescope; 5) meteoritic constraints on the physical and chemical conditions in the solar nebula; 6) the role of giant impacts in the structure and evolution of forming planets; 7) satellites and rings of giant planets as mini-laboratories to study the process of planet formation; 8) current census of extra-solar planets including new results from the Kepler and COROT missions as well as other facilities; 9) the essential chemical conditions for life and whether those are readily obtained through our current understanding of planet formation; and many other topics.

The conference will continue the usual format of invited lectures, extended discussion, and poster sessions. The meeting provides an excellent opportunity for young researchers to present their latest research results and to participate in the dynamic informal conversations that are typical of a Gordon Conference. We encourage young scientists, including graduate students and postdoctoral fellows, to attend. Special efforts will be made to promote interactions between invited speakers and junior participants and we expect to provide some financial support to facilitate the latter's participation.

For more information please visit the Gordon Research Conference website: http://www.grc.org/ [Source: NAI Newsletter]

Posted by Keith Cowing at 10:26 AM | Permalink | Comments (0)

7-14 February 2011
Marrakech, Morocco
Abstract Submission Deadline: 7 January 2011
Sponsored by the European Space Agency (ESA) Topical Team, Geomicrobiology for Space Settlement and Exploration.

Organizers: Charles Cockell (Open University, UK), Oliver Angerer (ESA), Gian Gabriele Ori (IRSPS, Italy and Ibn Battuta Centre, Morocco), Kamal Taj-Eddine (Universite Cady Ayyad and Ibn Battuta Centre, Morocco)

Geobiology in Space Exploration will be a meeting with talks and discussions that aim to cover the full range of the contributions of geobiology to space exploration and settlement. It will have two core purposes: 1) To contribute to building the community of people working in geobiology and applying the discipline to themes in space sciences and exploration; and 2) To develop a strategic document on the range of geobiology applications and possible space missions for ESA. The meeting will begin midday on Monday the 7th and will finish on Wednesday the 9th and will be held at the Universite Cadi Ayyad (Morocco). The meeting will then be followed by a voluntary field trip for interested participants.

Continue reading "Workshop and Fieldtrip: Geobiology in Space Exploration" »

Posted by Keith Cowing at 11:17 PM | Permalink | Comments (0)

Abstract Submission Deadline: August 10, 2010

2010 Geological Society of America National Meeting: T110, Mountain Formation and Landscape Evolution in the Solar System: Implications for the Origin of Life.

Organizers: Joseph Kula, Suzanne L. Baldwin

Session Summary: Terrestrial mountain formation in the solar system is related to thermal decay, tectonics, and impact events. The processes and timescales of landscape evolution will be explored with implications for the origin and search for life.

For more information: http://geosociety.org/meetings/2010/sessions/topical.asp?SponsorID=GSA+Planetary+Geology+Division

Posted by Keith Cowing at 9:43 PM | Permalink | Comments (0)

A NASA Astrobiology Institute-funded study led by Chris Dupont of the J. Craig Venter Institute indicates that environmental availability of trace elements over Earth's history influenced the selection of elements used by life as biological evolution progressed. Their results show that environmental concentrations of trace metals influenced which types of metal-binding proteins evolved, and the relative timing of their evolution.

The study implies that the geochemistry of the Archean ocean (>2.5 billion years ago) influenced both the evolution of metal-binding protein architectures and the selection of elements by the ancestors of modern Archaea and Bacteria (simple single cell organisms). Specifically, low Zn, Mo, and Cu concentrations in the Archean ocean likely prevented the widespread emergence and diversification of Eukaryotic life (including plants, animals, and fungi) until the oceans became oxic, relatively late in Earth's history. The study also revealed that although modern Archaea and Bacteria still predominantly use ancient metal-binding protein structures, most Eukaryotes use both early- and late- evolving structures. The paper appears in the May 24 Early Edition of PNAS.

Source: NAI Newsletter

Posted by Keith Cowing at 2:34 PM | Permalink | Comments (0)

The NAI is pleased to announce the 2010 Selections for the Lewis and Clark Fund for Exploration and Field Research in Astrobiology.

1. Knicole Colon, U Florida, travel to Spain for her project, "From Hot-Jupiters to Super Earths: Characterizing Transiting Extrasolar Planets with GTC/OSIRIS".

2. Andrew Czaja, U Wisconsin, travel to Australia for a "Field Trip to Explore Archean and Proterozoic Geology of Western Australia".

3. Jason Huberty, U Wisconsin, travel to Australia, for the "Fifth International Archean Synposium Field Trip to the Pilbara Craton, including the Fortescue and Hamersley Basins".

4. Michele Knowlton, Arizona State U, travel to Yellowstone National Park to examine nitrogen fixation occurring within microbial mats.

5. Nancy McKeown, U California, Santa Cruz, travel to Arizona, for a "Spectral Study Of the Painted Desert, AZ, to "Characterize Clay Alterations Environments and Provide Implications for Astrobiology at Mawrth Valis, Mars, a Likely Mars Science Laboratory Landing Site".

6. Elizabeth Percak-Dennet, U Wisconsin, travel to Australia, "Linking Laboratory and Field Studies of the Mineralogical and Iron Isotope Composition of Banded Iron Formations in Western Australia".

7. Matthew Urschel, Montana State U, travel to Alberta, Canada to examine "Iron Reduction in the Subglacial Sediments of Robertson Glacier, Canada".

For more information: http://astrobiology.nasa.gov/nai/funding/lewis-and-clark

Source: NAI Newsletter

Posted by Keith Cowing at 9:25 PM | Permalink | Comments (0)

This amendment delays the proposal due date for Appendix C.7, Outer Planets Research (OPR) Program. The program element in ROSES-2009, Appendix C.7, Outer Planets Research (OPR), solicits proposals for diverse scientific investigations that contribute to the understanding of the outer Solar System, including the giant planets, their satellites, and smaller solid bodies including comets, asteroids, and Kuiper Belt objects. The program includes both data analysis from NASA missions and fundamental research.

Continue reading "ROSES-09 Amendment 17: New Due Date, Start Date and Clarification for C.7, Outer Planets Research (OPR) Program" »

Posted by Keith Cowing at 9:51 AM | Permalink | Comments (0)

NAI's Deep Time Drilling Project supported the drilling of several pristine cores from ancient rocks in Western Australia in 2004, and a new paper in Science, led by University of Washington astrobiologists, outlines results from the analysis of these cores. The nitrogen isotope values in the core from the 2.5-billion-year-old Mount McRae Shale vary over 30 meters, evidently recording a temporary change from an anaerobic to an aerobic nitrogen cycle, and back again to anaerobic. Other data suggest that nitrification occurred in response to a small increase in surface-ocean oxygenation. The data imply that nitrifying and denitrifying microbes had already evolved by the late Archean and were present before oxygen first began to accumulate in the atmosphere.

[Source: NAI Newsletter]

Posted by Keith Cowing at 12:10 AM | Permalink | Comments (0)

An ecosystem discovered 2.8 kilometers underground in the Mponeng Gold Mine near Johannesburg, South Africa two years ago has now been shown to comprise only a single species of microbe, existing on energy from radioactivity, completely independently of the Sun. The community of rod-shaped bacteria of the species Desulforudis audaxviator was discovered in 2005-06 by members of the NAI's Indiana-Princeton-Tennessee Astrobiology Initiative (IPTAI) Team. Their current results are presented in the October 10th issue of Science.

Continue reading "Life Without the Sun" »

Posted by Keith Cowing at 8:17 PM | Permalink | Comments (0)

Members of NAI's University of Wisconsin, Madison team have a new paper in Earth and Planetary Science Letters presenting their analyses of 4.35 - 3.36 billion year old detrital zircons from the Jack Hills, Western Australia.

Continue reading "Jack Hills Zircons: New Information About Earth's Earliest Crust" »

Posted by Keith Cowing at 6:04 PM | Permalink | Comments (0)

Join us for the next NAI Director's Seminar on Monday, February 4th at 11am PST. The seminar, "The Effect of Protoplanetary Disk Dispersal on Planet Formation," will be given by David Hollenbach of NASA Ames Research Center. For information on how to join the seminar, go to: http://nai.arc.nasa.gov/seminars/seminar_detail.cfm?ID=117.

Continue reading "NAI Director's Seminar: The Effect of Protoplanetary Disk Dispersal on Planet Formation" »

Posted by Keith Cowing at 1:37 PM | Permalink | Comments (0)

Date: December 6-7th, 2007
Time: TBA
Venue: NASA Ames Research Center, Auditorium, Building N-245, Mountain View, CA

Organizing Committee: Ignacio Mosqueira (NASA Ames/SETI Institute), Dale Cruikshank (NASA Ames) Owing to spacecraft missions and groundbased observations, we possess a wealth of Solar System data. The richness of the observations should provide a solid foundation for our understanding of the early history of the Solar System. Yet, this abundance also means that in practice one must subdivide the problem into more manageable pieces. While this is a practical approach, before reliable conclusions can be obtained in this way, they must survive consistency checks, and a battery of tests involving a sufficiently broad observational sample. Only then can we attain a deeper understanding of the origins of planetary systems in general, and the Solar System in particular.

Continue reading "Formation, Composition and Early Evolution of Outer Giant and Dwarf Planets and of their Satellites" »

Posted by Keith Cowing at 8:28 AM | Permalink | Comments (0)

Speaker: Tim Raub (Yale University), Date/Time: Monday, February 26, 2007 11AM PST

Background: Using atmospheric chemical models of a Snowball Earth, scientists from NAI's Alumni Virtual Planetary Laboratory Team showed that, during long and severe glacial intervals, a weak hydrological cycle coupled with photochemical reactions involving water vapor would give rise to the sustained production of hydrogen peroxide. The peroxide, upon release from melting ice into the oceans and atmosphere at the end of the snowball event, could mediate global oxidation events.

Continue reading "NAI Director's Seminar "New and Emerging Perspectives on Late Precambrian 'Snowball Earth' Glaciation"" »

Posted by Keith Cowing at 1:19 AM | Permalink | Comments (0)

Philosophical Transactions of the Royal Society (B). Organised and edited by Charles Cockell, Sydney Leach and Ian Smith Published August 2006

Continue reading "Conditions for the Emergence of Life on the Early Earth: Special Issue Special Issue" »

Posted by Keith Cowing at 9:50 PM | Permalink | Comments (0)

Automated Drilling Field Demonstrations Exceed Goals, Go "Naked" in Haughton Crater 2006 DAME Tests

To look for ice or especially organics on Mars, we will need to drill below the oxidized and irradiated surface, probably at least 1-2m. Hardened subsurface ice layers aren't going to be addressed with lightweight scoops on manipulator arms, drills will be needed. But drilling is an art form on Earth, even "automated" offshore oil drilling platforms have control rooms full of people watching and adjusting the drilling.

Posted by Keith Cowing at 8:38 PM | Permalink | Comments (0)

Cassini Radar Finds Hydrocarbon Lakes on Titan

"The Cassini spacecraft, using its radar system, has discovered very strong evidence for hydrocarbon lakes on Titan. Dark patches, which resemble terrestrial lakes, seem to be sprinkled all over the high latitudes surrounding Titan's north pole. Scientists have speculated that liquid methane or ethane might form lakes on Titan, particularly near the somewhat colder polar regions."

Posted by Keith Cowing at 4:18 PM | Permalink | Comments (0)

Join NAI for the Polycom and WebEx broadcast of the second annual Summer Student Seminar Series. The talks will be given on Friday, July 28th and Friday August 11th at 12:00pm PDT (9:00am HT/1:00pm MDT/2:00pm CDT/3:00pm EDT.)

Continue reading "Second Annual Summer Student Seminar Series Begins July 28" »

Posted by Keith Cowing at 7:56 AM | Permalink | Comments (0)

Undersea Vehicles to Study Formation of Gold and Other Precious Metals On the Pacific Ocean Floor, WHOI

"The joint expedition includes a 32-day WHOI research program funded by the U.S. National Science Foundation to the Pacmanus vent sites in the Eastern Manus Basin. The remotely operated vehicle Jason will be used to survey and map the vent areas around an Ocean Drilling Program hole drilled in 2000."

Posted by Keith Cowing at 12:46 AM | Permalink | Comments (0)

NAI congratulates Dr. Sean C. Solomon, Principal Investigator of Carnegie Institution of Washington's NASA Astrobiology Institute and Director of the Department of Terrestrial Magnetism of CIW, on his receipt of the Caltech Distinguished Alumni Award on May 20.

Continue reading "Solomon Receives Caltech Distinguished Alumni Award" »

Posted by Keith Cowing at 11:55 PM | Permalink | Comments (0)

The ISBOX-II expedition lead by Eric Gaidos of the University of Hawaii NAI team will drill and sample a subglacial lake for microbiology and geochemistry. The expedition takes place June 6-13, 2006. Details and progress of "ISBOX 2" can be found at: http://www.ifa.hawaii.edu/UHNAI/isbox2.htm [Source: NAI Newsletter]

Posted by Keith Cowing at 11:51 PM | Permalink | Comments (0)

The Center for Meteorite Studies at Arizona State University is pleased to announce the 40th Anniversary of the Nininger Award for undergraduate and graduate students pursuing research in meteoritical sciences.

Continue reading "ASU Award for Students Pursuing Research in Meteoritical Sciences" »

Posted by Keith Cowing at 12:34 AM | Permalink | Comments (0)

The NAI is sponsoring an expedition to one of the Earth's most active volcanic regions. Jake Maule of the Carnegie Institution of Washington, will lead the expedition to the Klyuchevsky Volcano group in eastern Russia, from August to October of 2006. Developed under guidance of the Kamchatka Tiger Team, including representatives of the NAI, the Russian Astrobiology Center and the Australian Centre for Astrobiology, the expedition will obtain microbial mats, gas, water, mud, and rock samples from drill sites and vents in the hot springs and permafrost of the Kamchatkan peninsula. (POC: Jake Maule: j.maule@gl.ciw.edu)

Posted by Keith Cowing at 5:38 PM | Permalink | Comments (0)