April 2014

Monday, Apr 21
4:00 pm
2014 Yetadel Lecture: Sir Roger Penrose
Sir Roger Penrose
Emeritus Rouse Ball Professor of Mathematics
University of Oxford

Seeing Signals from Before our Big Bang?
Current cosmology presents the following picture: the origin of the entire universe was a vast explosion known as the "Big Bang", immediately followed by a brief period of exponential expansion called "inflation"; after this was a more sedate expansion which continued nearly until our current epoch, but now a second phase of exponential expansion, driven by "dark energy" is taking over.

In this talk I present a modified extension this picture whereby the universe consists of an infinite succession of "aeons", each of which started with its own "big bang" and ultimately continued to an exponential expansion to infinity - so our own Big Bang was not actually the ultimate beginning, but was the continuation of a previous aeon. Instead of having an inflationary phase, each aeon's ultimate exponential expansion plays a role that appears like inflation in the next.

I shall endeavour to explain how this confusing picture actually makes good geometrical and physical sense. Moreover, we see how signals can even pass through from one aeon to the next providing observational effects, some of which we do appear to be actually seeing, coming from an aeon preceding our own.

TAP Colloquia
Steward Observatory: Room N210
Tuesday, Apr 22
3:45 pm
LPL Colloquium: Dr. Stuart Bale
Dr. Stuart Bale
Space Sciences Laboratory
University of California, Berkeley

The kinetic solar wind and the NASA Solar Probe Plus mission
The solar wind expands into interplanetary space, from its origin in the superhot solar corona. The underlying physics responsible for coronal heating isn't clear, although mechanisms such as Alfven wave heating, magnetic reconnection, and shock heating have all been proposed and have merits. As the wind evolves into space, it continues to be heated as it expands - presumably by some wave-heating process. Recent measurements at 1AU show clearly the signatures of kinetic plasma physics and suggest that these effects are dominant at the wind source. In this talk, I'll give an overview of the problem, describe some of these recent measurements, and conclude with a discussion of NASA's Solar Probe Plus (SPP) mission. SPP will launch in 2018 and fly directly into the solar corona to make in situ measurements of the physical processes of coronal heating.

Host: Joe Giacalone
Kuiper Space Sciences: Room 312
Monday, Apr 28
12:00 pm — 1:00 pm
Brown Bag Colloquium: Dr. Bashar Rizk
Dr. Bashar Rizk
OCAMS Instrument Scientist
University of Arizona - Lunar and Planetary Laboratory
Kuiper Space Sciences: Room 309
Tuesday, Apr 29
3:45 pm
LPL Colloquium: Dr. Bashar Rizk
Dr. Bashar Rizk
OCAMS Instrument Scientist
University of Arizona - Lunar and Planetary Laboratory

Imaging Science, OCAMS and Bennu
Modern planetary imagers operate at ever-greater resolution, throughput and data loading. Their scientific goals remain the same: 1) reveal new solar system phenomenon, 2) document the visual history of its surfaces and 3) provide a context for physical and chemical anyalysis of meteorites and in situ samples. The trio of imagers in the OSIRIS-REx Camera Suite-OCAMS-are reviewed from that point of view. OCAMS' expected scientific return is discussed while noting the suite's critical function as a mission system to enable the selection of a primary sample site. In addition, Bennu's status as a microgravity object is emphasized. It will serve as a high-fidelity and readily observable physical analog to the many million billion planetesimals that contributed to the formation of the planets and that, directly or indirectly, currently populate the Kuiper Belt, Oort Cloud, Jovian Trojan points and, perhaps, the Main Belt and Near-Earth Asteroid populations.
Kuiper Space Sciences: Room 312