Wednesday, May 6, 2009

SETI Institute YouTube Channel

SETI Institute YouTube Channel is now live at http://www.youtube.com/setiinstitute

Our most recent lecture videos are now available at SETI Institute's YouTube Channel.

You can subscribe to lecture videos via YouTube or follow me on twitter to get the scoop on video uploads.

Monday, May 4, 2009

04/29/2009 - Experimental determination of the effect of salts, regolith, and wind on the stability of water under Martian conditions

Julie Chittenden

Many fundamental processes on Mars require an understanding of the temperature and pressure conditions at the Martian surface. In particular, the stability of liquid water is a key factor in formation of gully features, and is significant to the possibly for life on Mars. Dr. Chittenden will discuss her experimental work on the stability of water under martian conditions, performed at the University of Arkansas in the Mars planetary simulation chamber. Her results suggests concentrated brine water may remain liquid on the Martian surface longer than previously thought. She will also report the effect of a regolith layer on subsurface ice sublimation and the effect of wind on the stability of surface water ice on Mars.

watch video ( at the SETI Institute Channel from YouTube )

4/22/2009 - First Things in the Universe

Tom Abel, Kavli Institute for Particle Astrophysics and Cosmology Laboratory, Stanford University

The first structure to form in the Universe can now be predicted from ab initio simulations starting with the known initial conditions of our Universe. What is found is a rich history with massive stars, black holes, UV radiation, and hydrogen molecules among others playing significant roles. Using supercomputer simulations allows us to visually show the origin of the first stars, their demise and impact on their future, which is our past, in the Universe' first billion years.

play video

Monday, April 27, 2009

04/15/2009 - The Dynamic Lunar Environment

Jasper Halekas, UC Berkeley Space Sciences Laboratory

The lunar environment, serene and unchanging to the naked eye, seethes with plasma and electromagnetic activity. Plasma, photons, micrometeorites and energetic particles constantly bombard the lunar surface, producing a tenuous exosphere and a dynamic wake region, and charging the surface to electrostatic potentials reaching kilovolts, producing surface electric fields large enough to affect lunar ions and dust. Meanwhile, plasma interacts directly with crustal magnetic fields, producing perhaps the smallest magnetospheres in the solar system. Dr. Halekas will talk about how the Moon provides an ideal laboratory to study a variety of fundamental physics processes which are both interesting in their own right, and potentially applicable to Mars and other planets in the solar system.

play video

Wednesday, April 15, 2009

4/8/2009 - Convergent evolution of our own and extra-terrestrial intelligence

John McCarthy, Professor Emeritus, Computer Science Stanford University

Convergent evolution is the phenomenon of two or more species of widely different origins evolving extremely similar features in response to the same environmental opportunity. Our intelligence and that of aliens with whom we might communicate are likely to have converged considerably and to converge further in the future. Much of this future convergence is likely to be artificial, i.e. electronic. Professor McCarthy will discuss some possibilities.

play video

Wednesday, April 8, 2009

04/01/2009 - Weathering on Icy Satellites: Probing the Near Surface Using Infrared Spectroscopy

Rachel Mastrapa, NASA Ames Space Sciences Division and SETI Institute

Infrared spectra of icy satellites contain information about the surface composition and the phase state of those materials. For example, the phase of H2O-ice can be used to interpret the temperature and radiation history of an icy surface. Optical constants derived from laboratory data are needed to create model spectra for comparison to observations and may lead to a new understanding of surface processes.

play video

Wednesday, April 1, 2009

03/18/2009 - Discovery of Strong Cycles in Fossil Diversity

Richard Muller, Lawrence Berkeley Laboratory, UC Berkeley

Richard Muller and his collaborators have recently analyzed the most complete record of marine animal fossils ever compiled, the "Compendium" of Jack Sepkoski, which lists all known fossil marine animal genera back 542 million years. When the fossil diversity (number of distinct genera) is plotted, it shows a very strong 62 Myr cycle. The cycle is particularly evident in the species that endured for relatively short times, as shown in the diagram below (published in Nature, vol 434, 208-210, 10 March 2005).

play video

Wednesday, March 18, 2009

03/11/2009 - Tools for Probing the Universe: from the Smallest to Largest and All Scales In Between

Jeffrey Scargle, NASA Ames Space Science Division

Jeff Scargle will describe non-standard data analysis methods for extracting scientific information from time series and other data. Examples include large scale structure in the distribution of galaxies, detection of extrasolar planets, "meta-analysis" of clinical studies and psychic phenomena, variability of Fermi Gamma Ray Space Telescope sources, and the search for quantum gravity effects at the smallest possible space-time scales.

play video

Wednesday, March 11, 2009

03/04/2009 - Google Earth, now with Mars!

Ross A. Beyer, SETI Institute and NASA Ames

Google, Inc., has released Google Earth 5.0 which contains a Mars 3D mode. Working with engineers at Google, we helped collect, parse, and organize the vast store of Mars geospatial data available to the public into a form that could be used by Google Earth. The Mars mode presents data acquired both from orbit and on the surface, presented fully integrated into the Google Earth geospatial browser. Ross will cover a brief history of the project, take you on a detailed tour of all of the features, and answer your questions about using Mars mode for science, education, or fun, as well as answering questions about how to view your own data in the client. The team behind this talk includes NASA Ames engineers Matt Hancher and Michael Broxton.

play video

Friday, February 27, 2009

02/25/2009 - Interstellar and Early Solar System Organics in Samples from Comet Wild 2

Scott Sandford, NASA Ames Space Science Division

The Stardust mission successfully returned samples from Comet Wild 2 in 2006. Studies of these samples have confirmed the presence of organics, some of which appear to be similar to those found in meteorites and some of which looks unlike anything seen in extraterrestrial materials before. The presence of D and 15N excesses in many of the organics suggests they have an interstellar chemical heritage. The nature of these organics, and their possible relationship to interstellar environments will be discussed.

play video

02/18/2009 - Multiple Asteroid Systems: New Techniques to Study New Worlds

Franck Marchis, UC Berkeley and the SETI Institute

Since the discovery of Ida’s companion Dactyl in 1993, the number of known multiple asteroids has been continuously increasing and ~165 of them are now known. Since 2003, Dr. Marchis and his colleagues have been conducting a large survey of these interesting and diverse populations using various ground-based telescopes and techniques, such as high angular resolution imaging, lightcurve photometry, and VIS/NIR spectroscopy, and also the Spitzer and Hubble space telescopes. Dr. Marchis ' talk will cover the latest insights into these multiple systems, such as the sizes and shapes of their components, their bulk-density and their orbital parameters, which are key to understanding how they formed and evolved.

play video

10/29/2008 - Giant Planet Formation

Dr. Jack Lissauer, Space Sciences Division, NASA Ames Research Center

The observed properties of giant planets, models of their evolution, and observations of protoplanetary disks all provide constraints on the formation of gas giant planets. The four largest planets in our Solar System contain considerable quantities of hydrogen and helium, which could not have condensed into solid planetesimals within the protoplanetary disk. The preponderance of evidence supports the core nucleated gas accretion model of formation of the giant planets. According to this model, giant planets begin their growth by the accumulation of small solid bodies, as do terrestrial planets. However, unlike terrestrial planets, the growing giant planet cores become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates. During this talk, Dr. Lissauer will present the first models of giant planet formation that account for both the planet's internal energy budget and gas flows within the protoplanetary disk.

play video

Wednesday, February 25, 2009

01/28/2009 - Surface modifications by winds on Earth, Mars, Venus, and Titan

Ron Greeley, Regent's Professor, Arizona State University


Windblown dunes, ripples, and erosional features are seen on Earth, Venus, and Titan, while on Mars these features are ubiquitous and reflect the dominant agent of surface modification. Although the fundamental process is similar, the environments on these planetary objects are substantially different. Simulations conducted in the Planetary Aeolian Laboratory at NASA-Ames, coupled with field work and modeling, enable analyses of wind-related features and processes on planetary surfaces.



play video

11/05/2008 - The Allen Telescope Array: A Radio Survey Telescope for the 21st Century

Don Backer and Jill Tarter

Jill Tarter will talk about the large survey SETI observing programs to be undertaken by our in-house team over the next decade, the SETI observing projects from external proposers that have been allocated array time during this current observing period, some recently suggested 'far out' SETI observing strategies (not all relating to the ATA), our first thoughts about beginning OpenSETI, our recent successful demonstrations with SonATA0, and our plans for moving forward towards a Software Defined Radio Telescope (SDRT).

Don Backer will talk about early science with the ATA, which has focused on transient source searches, broad-band spectra of Active Galactic Nuclei objects (AGNs) and diffuse atomic hydrogen in clusters of galaxies. Exploratory observations of the linear polarization of AGNs have been done in a program that will probe intergalactic magnetic fields. A special transient source program was conducted -- the Fly's Eye -- to look for giant pulses from distant galaxies.

play video

10/22/2008 - MIPSGAL: MIPS/Spitzer Survey of the Galactic Plane

Dr. Sachindev Shenoy

MIPSGAL is a survey of the Galactic plane at 24 and 70 microns using Multiband Imaging Photometer for Spitzer (MIPS) Space Telescope. This is one of the most sensitive survey in the mid-infrared of our Galactic plane. In this talk, Dr. Shenoy shall describe the science requirements, strategies, and data reduction of the survey program. He will outline some of the science topics that can be explored by the community using his team's data. In particular he will talk about the discovery of over 8000 Debris Disk candidates in the Galactic plane using the MIPSGAL 24 micron point source catalog.


play video

09/24/2008 - Black Holes: End of Time or a New Beginning?

Prof. Roger Blandford, Stanford Linear Accelerator and Physics, Stanford University

Black holes are popularly associated with death and destruction (excluding romances dealing with the redemptive properties of wormholes). However, their conventional astrophysical role is now seen as regenerative and they play a major role in the formation and evolution of galaxies stars and, arguably, organic molecules. Some possible ways in which they may impact the research of the SETI Institute will be discussed and ways in which they may have played a role in the history of our solar system will be briefly discussed.

play video

Wednesday, February 18, 2009

02/05/2008 - The Hunt for Hidden Dimensions

JoAnne Hewett, Professor at SLAC, Stanford University

Extra dimensions of space may be present in our universe. Their discovery would dramatically change our view of the cosmos and would prompt many questions. How do they hide? What is their shape? How many are there? How big are they? Do particles and forces feel their presence? This lecture will explain the concept of dimensions and show that current theoretical models predict the existence of extra spatial dimensions which could be in the discovery reach of present and near-term experiments. The manner by which these additional dimensions reveal their existence will be described.

Watch video

01/21/2009 - Roundup at the Kepler Corral: the Race to Detect the First Earth-sized Planet in the Habitable Zone of a Sunlike Star

Dr. Jeffrey Van Cleve, Ball Aerospace & Technologies Corp

The Kepler Mission http://www.kepler.arc.nasa.gov is designed to detect transits of Earth-size planets orbiting in the "habitable zone" (HZ) around main-sequence stars of apparent visual magnitude 9 through 14, of F through M spectral type, by means of differential photometry of ~100,000 stars in the constellation Cygnus. Jeff will discuss the box in temperature-diameter space ("The Corral") that Kepler was designed to search, and show the population of extrasolar planets known from ground-based radial velocity and gravitational lensing observations. He will present a calculation of the distance between Earth and the nearest transiting planet likely to be discovered by Kepler, and compare it to results of an all-sky planetary transit survey mission similar to TESS (The TESS PI has commented that "...when starships transporting colonists first depart the solar system, they may well be headed toward a TESS-discovered planet as their new home"). He will end with some speculation on why the end of the nominal Kepler mission coincides with the end of the Mayan calendar (and possibly the end of the world as we know it) on Dec. 21, 2012.

Watch video

01/14/2009 - Laboratory Studies of Water Ice Cloud formation under Martian Conditions

Dr. Laura T. Iraci, NASA Ames Research Center

Water ice clouds are an important part of the martian hydrological cycle, influencing the water and energy budgets. Microphysical models can be used to study the connections between cloud formation and water distribution throughout the system (for example, as surface frost layers), but only if the intricacies of cloud formation and growth are understood and properly parameterized. To that end, we have performed laboratory studies of water ice nucleation on a variety of surrogate materials and have found that initiation of ice is more difficult than often presumed. We will report these results, along with preliminary growth rate observations.

Watch video

01/07/2009 - Mission to a Potentially Threatening Asteroid

David Morrison, NASA Ames Research Center

Near Earth Asteroids (NEAs) are interesting to both planetary scientists and those who are concerned about protecting against their impacts. The first step, now well underway, is to find them (with the Spacegaurd Survey). Next we need to characterize NEAs using small spacecraft missions. We are especially interested in the sub-km NEAs, since they are the most likely to hit the Earth and also the most accessible targets for human flights beyond the Moon. This talk focuses on a low-cost rendezvous mission to NEA Apophis, with the goal of characterizing both the asteroid and its orbit.

Watch video