UWAB hosts a biannual colloquium series every spring and fall, featuring speakers from both UW and other institutions presenting on a wide range of astrobiology related topics. Here, you can find the schedule for upcoming colloquia and seminars, as well as an archive of abstracts and live recordings of past events.
If you would like to be notified about upcoming events, you can email us
and request to be added to our events mailing list.
You can also watch a live broadcast of our events by logging in remotely
during the scheduled colloquium time!
**Events are held in PAA A118, Tuesdays at 3:00PM**
The UWAB colloquium is not currently in session, but will return in Fall 2014.
Choose Your Own Adventure: Multiplicity of Planets among the Kepler M Dwarfs
The Kepler data set has furnished more than 130 exoplanetary candidates orbiting M dwarf hosts, nearly half of which reside in multiply transiting systems. I investigate the proposition of self-similarity in this sample: whether a single stellar system architecture explains the multi-planet yield of Kepler. In fact, the data much prefer a model with two distinct modes of planet formation around M dwarfs, which occur in roughly equal measure. One mode is one very similar to the Solar System in terms of multiplicity and coplanarity, and the other is very dissimilar. I investigate astrophysical explanations for this feature of Kepler's multiple planet population orbiting small stars, and discuss the relative unlikelihood of selection bias or unusually high false positive rates as an explanation. By folding in recent analyses about planet multiplicity versus eccentricity, I conclude with a description of how this two-mode model informs both our understanding of planet formation and our search for habitable worlds.
(Associate Professor of Physics, University of Idaho)
Life, Jim, but Not as We Know It: Prospects for Life in Titan's Hydrocarbon Seas
The prerequisites for life are thought to be: (1) a liquid solvent; (2) chemical building blocks; and (3) an energy source. Life like we have on the Earth uses water for its solvent and organic molecules for its building blocks. Hence searches for Earth-like life can focus on habitable zones around stars where liquid water can be stable on planetary surfaces. But is water the only solvent in which life can exist? Though more exotic solvents (like ammonia, liquid nitrogen, or supercritical carbon dioxide) may exist in extrasolar systems, the only surface liquids outside of Earth that we know about today occur on Saturn's smoggy moon Titan. I will describe these seas, their chemistry, and hydrology, with an eye toward whether they could serve as possible abodes for life. Recent Cassini discoveries show evaporitic bathtub rings and 'salt' flats around seas, which indicates that at least some materials do dissolve in the lakes. I will also discuss new Cassini RADAR evidence for compositional variations between the seas, and VIMS observations that may show the first sea-surface waves ever seen outside of Earth.
Kevin Zahnle (NASA Ames Research Center)
Veteran's Day. No colloquium.
(PostDoctoral Fellow, University of Illinois at Urbana-Champaign)
The origin of microbial species: Peering into microbial genomes to understand microbial adaptation into new ecological niches
The evolution and spread of microbial communities into new ecological niches has profoundly shaped our planet’s biogeochemical cycles and habitability over geological time. However, the molecular mechanisms of microbial adaptation to the environment are not well understood, yet understanding these processes can give us insights into how microorganisms have co-evolved with the planet throughout its history. We are examining archaeal genomes isolated from Yellowstone hot springs to ask how the acquisition of new genes affects the evolutionary trajectory of a microbial lineage, and to determine what types of genes are most frequently transferred as a means to adapt to new environments. Through these techniques we can also begin to reconstruct evolutionary history, and trace these processes to the origin and spread of key metabolisms during the Archaean era. Through this we hope to shed light on the mechanisms by which microorganisms adapt to new ecological niches, and to understand how metabolic networks spread across the biosphere.
(Principal Investigator, Intrinsyx Technologies Corporation- NASA-AMES Research Center)
Metal and Metalloid Tolerance Mechanisms of Metal Hyperaccumulator Plants and their Applications for Human Extraterrestrial Colonies
Worldwide more than 400 plant species have evolved the extreme ability to hyperaccumulate the following elements in their shoots; metals (nickel, zinc, cadmium, cobalt, or manganese) the metalloids (arsenic and selenium). Of these species, almost one-quarter are Brassicaceae family members, including numerous species that hyperaccumulate metals up to 3% of shoot dry weight. Brassicaceae model species have been developed to study the molecular mechanisms of metal tolerance and hyperaccumulation and our recent findings hold promise for improving plant growth in metal enriched environments which is useful for rhizofiltration of water, phytoremediation of soils and for increasing the mineral nutrition of crop plants. The knowledge gained by researching metal hyperaccumulator plants clearly holds potential value for developing plant based applications for use in the phytoremediation of earth’s polluted environments and also for use in developing bioengineered life support systems required for long term manned space travel and for in situ resource utilization (ISRU), which are required processes for the long term human colonization of extraterrestrial planetary bodies.
Missed the last seminar series? See our archive for abstracts and video recordings of all past talks from 2003 - present.