SETI Institute Projects and Programs (Listed Chronologically)

Modeling the Diversity of Protoplanetary Disks

Monday, November 03 2014 - 7:26 pm, PST
We propose a multiwavelength analysis of gaseous protoplanetary disks by modeling archival Spitzer, ISO and Herschel infrared line emission data using our gas disk thermo-chemical models. We will use archival infrared, optical, UV and X-ray data, supplemented with ground-based observational data from literature for a sample of 12 disks spanning a range of stellar masses, disk conditions and evolutionary epochs.

COLLABORATIVE RESEARCH: Understanding Protoplanetary Disk Winds and Planet Interactions via Disk Emission Lines

Monday, November 03 2014 - 7:15 pm, PST
This collaborative research proposal will use an integrated approach that combines theory and observations to systematically study disk winds, evolution, and dispersal. We will analyze a unique dataset of high resolution optical and mid-infrared spectra for a sample of 55 disks around low and intermediate-mass stars at different stages of evolution. We will model the observed line emission fluxes and profiles using state-of-the-art thermochemical and 2-D hydrodynamical models for a sub-sample of disks, selected to represent various evolutionary epochs, to understand photoevaporative flows and to estimate resulting mass loss rates. Using hydrodynamical models to study the impact of planetary torques on disk structure, and thermochemical models to predict observable diagnostics, our study will distinguish rim emission due to photoevaporation from that due to planet-induced gaps and holes. This study will reveal the structure of the inner disk, calculate accretion rates, and probe emission characteristics when gas accretes past a planet. We will further seek new emission line diagnostics of photoevaporative winds and planet-disk interactions and make predictions for future observations using ALMA and other high resolution, high sensitivity facilities.

Disk Evolution, Dispersal and Planet Formation

Monday, November 03 2014 - 4:02 pm, PST
We propose theoretical investigations of protoplanetary disk evolution and dispersal to study how the spatial and temporal distribution of gas and solids in disks affect their planet-forming potential. We will determine the properties of disks and host stars that are most favorable to the formation of planetary systems by conducting a parameter survey using our theoretical models. These will include stellar mass, stellar X-ray and UV luminosities, level of ionization in the disk, disk initial angular momentum, gas to dust mass ratio and dust physical and chemical properties.

Preformed Complex Organic Molecules from the Matrix of Magnetic Minerals

Monday, November 03 2014 - 3:48 pm, PST
We propose an in-depth study of the formation of Cn-H-O-N-S entities in the matrix of laboratory-grown MgO and gem-quality olivine crystals from the upper mantle, using IR spectroscopy and ultrahigh resolution mass spectrometry of solvent extracts from crushed powders. The work is relevant to prebiotic chemistry in the Exobiology Program.

A Study of the Atmospheres of Brown Dwarfs and Extra Solar Planets and the Sources of Atomic and Molecular Opacity in Their Atmospheres

Monday, November 03 2014 - 3:46 pm, PST
The research topics to be undertaken under the new agreement are mainly a continuation of the current work. This includes modeling of observations of brown dwarfs and extra solar planets and investigations of new modeling techniques that are needed to handle the demands of better and more comprehensive data. We also wish to include more realistic chemical models in our calculations as new observations seem to indicate the need for a more comprehensive set of models that includes the possibility of non-equilibrium chemical abundances and dynamically active atmospheres.

Aeolian activity in the last 400 ka driven by insolation changes: Can global and mesoscale atmospheric modeling explain when and how Meridiani Planum ripples last migrated?

Monday, November 03 2014 - 3:39 pm, PST
The climatic system of Mars, composed chiefly of the atmosphere and the uppermost meters of the planet's crust, is primarily driven by the absorption of shortwave solar radiation (and modulated by the emission of longwave radiation to space). The chief parameters which control the insolation over seasonal and longer intervals are the axial obliquity, the orbital eccentricity, and the season (Ls) of perihelion. Large variations in insolation can result from relatively modest changes in the values of one or more insolation parameter(s). Such significant insolation changes may translate into potentially large changes in atmospheric density and winds, two of the most important parameters for aeolian surface processes.

Unraveling the sedimentary history of gypsum sand in the northern polar sand seas of Mars

Monday, November 03 2014 - 3:35 pm, PST
In 2005, a large quantity of the mineral gypsum was unexpectedly identified in the high latitude dune sands of Olympia Undae. Because gypsum is formed in the presence of liquid water, the discovery of this extensive deposit has important implications for the climatic and sedimentary history of the currently cold and dry north polar region of Mars. Indeed, the presence of this mineral within Amazonian strata (< ~3.5 Ga) could have global implications, because it contradicts the current view that sulfate minerals only formed in abundance on Mars much earlier in the planet's history, during the Hesperian (or Theiikian) Epoch (> ~3.5 Ga). Images from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) indicate that gypsum sand grains appear to concentrate at dune crests, but it is not known whether aeolian processes alone could be responsible for this effect, nor what the significance of this pattern may be. Despite its potential importance in unraveling Mars' geological history, the origin of the gypsum and its role in sedimentary and polar processes is disputed and poorly constrained.

The Astrobiology Summer Science Experience for Teachers (ASSET) at the SETI Institute

Monday, November 03 2014 - 12:42 pm, PST
We propose to continue the Astrobiology Summer Science Experience for Teachers (ASSET) at San Francisco State University, California Academy of Sciences, Golden Gate National Park Crissy Field, and the SETI Institute. First held in 2004, ASSET is an on-going, exemplary professional development workshop aligned with NSES Professional Development, Content and Teaching Standards. It blends science content and pedagogy with leadership skills development. ASSET is 6 days of instruction and practice that parallel 6 astrobiology curriculum modules. The workshop offers 3 graduate science education credits (participants pay tuition), which requires the extended schedule. The ASSET workshop is intense and exciting, interactive and content rich, with presentations by leading astrobiology researchers from the SETI Institute, NASA, and the California Academy of Sciences.

Structural and Compositional Evolution of Saturn's Rings

Monday, November 03 2014 - 12:36 pm, PST
We propose to study the compositional and structural evolution of Saturn's main rings subsequent to meteoroid bombardment, with the ultimate goal of obtaining a better understanding of the rings' origin.

Dynamical Disks: Primary Accretion and Planetary Rings

Monday, November 03 2014 - 12:34 pm, PST
The main objective of this proposed research is the continued advancement in our understanding of the growth of dust to planetesimals in both nebular and subnebular environments and the structural and compositional evolution of Saturn’s rings.