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Amy Mainzer, From Dust Motes to Icy Mountains: Asteroids and Comets
Our solar system teems with asteroids and comets, which range in size from tiny dust particles to gigantic mountains that are worlds in their own right. While most of these objects remain in stable orbits that whirl them around the Sun for billions of years, every now and again something changes: Some objects can be perturbed into orbits that encounter Earth. In the last few decades, astronomers have begun systematic searches for potentially Earth-impacting asteroids and comets, and in the process have learned much about Earth’s nearest cosmic neighbors. As study of the distant universe has advanced, so has our understanding of the contents of our own solar system, and its potential to affect life on Earth.
Catherine Espaillat, Baby Planets and their Nurseries
We know that planets are born in the protoplanetary disks that surround stars when they are young. How these disks evolve into planetary systems is a fundamental question in Astronomy. Observations have revealed remarkable structures in disks that may indicate the presence of newly born planets. This talk reviews these key observations and compares them to current theoretical predictions of planet formation. Finally, Dr. Espaillat discusses possibilities for future progress.
Laurance Doyle, Humpback Whale Song as an Intelligence Filter for SETI
We have been applying the mathematics of information theory—originally developed for human communication systems and computers—to humpback whales in order to measure the complexity of their vocalizations. Is their "language" as complex as ours, or even more complex? Are there general rules for communicating knowledge that even messages from extraterrestrial intelligence (ETI) will have to obey? As astrobiology uses Antarctica as a proxy for Mars, so we are using non-human but complex communication systems as a proxy for an ETI signal if and when one may be received. Humpback whales grew up on the same planet, and around the same star, as humans did, but their communication systems are certainly not human! Thus we can deprovincialize our thinking and approach to the detection of intelligent life in space.
Belinda Wilkes, Celebrating 20 years with NASA's Chandra X-ray Observatory
The launch of NASA's Chandra X-ray Observatory in 1999 brought X-ray astronomy into the main stream, with 10 times the resolution and the ability to see objects 100 times fainter than previous x-ray satellites.
As Chandra celebrates its 20th year of operations, Dr. Wilkes will review some of the major discoveries and highlights of its scientific progress to date. This encompasses determining whether habitable exoplanets can survive the birth of their stars, to finding very distant supermassive black holes when the Universe was 10 percent of its current age, and everything in between: the birth and death of stars, merging galaxies and black holes, and unexpectedly chaotic clusters of galaxies.
What does the future hold for new Chandra scientific opportunities now and over the next decade, and what might follow Chandra when it ends its illustrious career?
Michael Busch, Near Earth Asteroids, Space Missions, and the Impact Hazard
The near-Earth asteroids (NEAs) are a population of objects on orbit around the Sun that cross or come near the orbit of Earth; remnants of material from the early solar system that never accreted into planets. NEAs are accessible targets for space missions, but also pose a hazard due to potential future impacts onto Earth. Dr. Busch, of SETI Institute, will review the near-Earth population and efforts to address the asteroid impact hazard. He will also discuss past, current, and future missions to near-Earth asteroids, including missions by NASA, ESA, JAXA, the Chinese National Space Agency, and potentially other groups.
Juna Kollmeier, Mapping the Universe, The Sloan Digital Sky Survey
The Sloan Digital Sky Survey is an unprecedented all-sky spectroscopic survey of over six million objects. It is designed to decode the history of the Milky Way galaxy, trace the emergence of the chemical elements, reveal the inner workings of stars, and investigate the origin of planets. SDSS will also create a contiguous spectroscopic map of the interstellar gas in the Milky Way and nearby galaxies that is 1,000 times larger than the state of the art.