SETI Institute Weekly Colloquium
At the Microsoft Campus in Mountain view
1065 La Avenida St, Mountain View CA
FREE and open to the public. Tuesdays, noon to 1pm
The Search for Extraterrestrial Intelligence is a blind search across many dimensions—space and time being the most obvious. Every good SETI researcher does their very best to make the minimal reasonable assumptions, but time and resources are always limited, so various strategic optimizations have been adopted. A potentially more efficacious approach is to simply cover as much of the search space as possible. The SETI Institute has made this the starting point of their ambitious and groundbreaking idea to survey the entire night sky, all night, every night at optical wavelengths. This talk will further detail the motivation and planned operation of this new instrument, a panoptic eye for interstellar laser pulses.
Dwarf galaxies tend to form stars inefficiently. Yet, blue compact dwarf (BCD) galaxies are a subset of dwarf galaxies that have intense and concentrated star formation (compared to typical dwarf galaxies). BCDs are thought to require a large disturbance to trigger their burst of star formation. A common theory is that the enhanced star formation in a BCD is the result of an interaction with another galaxy or a dwarf-dwarf galaxy merger. However, many BCDs are relatively isolated from other galaxies, making an interaction or a merger a less likely starburst trigger.
As part of the atomic hydrogen dwarf galaxy survey, LITTLE THINGS*, Dr. Ashley has studied the gaseous properties of six BCDs. Atomic hydrogen data allow us to explore the velocity fields and morphologies of the gas in BCDs, which may contain signatures of star formation triggers, such as gas consumption, a past merger, and interaction with previously undetected companions. If BCDs have formed through gas consumption or dwarf-dwarf mergers, then they would be useful analogs for galaxy formation in the early universe. Also, learning which large disturbance has triggered the burst of star formation in BCDs could be useful for understanding and modeling how/whether BCDs evolve into/from other types of dwarf galaxies.
In the last few years we have found that Mars' south polar cap has as much carbon-dioxide as Mars' current atmosphere. This raises numerous questions about how this massive deposit formed and what Mars was like when it was in the atmosphere. Using a combination of methods including spacecraft imagery, radar, and modeling we can start to answer some of these questions. Carver Bierson will discuss evidence that these deposits may have formed over several cycles of Mars atmosphere collapsing onto the surface and then sublimating back into the atmosphere.
History of Clays on Mars: How We Found Them and Why They are Important for Astrobiology