Dr. Terry Oswalt's Presentations
Digging in the Stellar Graveyard: How Astronomers Measure the Age of the Universe
Physics Department Colloquium, Thursday, February 5, 4:00 pm, Brace 211
The Universe 13.7 billion years old. We know this age to better than 5 percent uncertainty. It's pretty amazing that such an enormous age, spanning vastly more time than human beings have existed can even be measured. The Hubble Space Telescope was designed to specifically to determine that age of the Universe. As it turned out, ground-based techniques played an even more important role in pinning down this number. In this talk, Dr. Oswalt will discuss how astronomers measure ages of astronomical objects in general, and how dead stars called white dwarfs helped determine the age of the Universe and contributed to the discovery of dark matter and energy.
Chicken Little Was Right, the Sky IS Falling!
General Public Talk, Thursday, February 5, 7:30 pm, Union Auditorium, UNL City Campus
Asteroids and comets may preserve the only records of the physical and chemical processes which marked the beginning of the solar system 4.6 billion years ago. Most asteroids revolve about the sun between the planets Mars and Jupiter and are believed to be the rocky remnants of the minor bodies from which all planets accrete. Comets are bodies that come from far outside the orbit of Pluto, in a dark realm called the Oort Cloud, a large icy debris zone which surrounds the Sun. Over the last decade, the risk of impacts from comets and asteroids has been recognized as substantial and a number of research programs have been undertaken to find and categorize the most dangerous Near Earth Objects (NEOs). Dr. Oswalt will discuss how NEOs are found, the way impact risks are assessed, what the effects of an impact can be, and how the human species might respond to the threat of a major impact.
Searching for Life in the Universe: Where is Everyone?
General Public Talk, Friday, February 6, 8:00 pm, Behlen Observatory, Mead, NE
Is there life elsewhere in the universe? Over 300 planets outside the solar system are already known. How many of these other worlds might be home to simple living organisms? Have any planets developed intelligent life? And if intelligence is common in the universe, where is everyone? Over the next 20 years a radically new instrument, the Allen Telescope Array, will scrutinize the vicinities of millions of stars looking for faint radio signals. NASA plans space-based instruments capable of detecting the spectroscopic signatures of life on Earth-like planets during the same period. In this talk we will explore some of the factors that determine whether we are alone in the universe.
This talk is part of a public night at Behlen Observatory. The 30-inch telescope will be open for viewing celestial objects, weather permitting. Directions to Behlen Observatory
- Dr. Oswalt is Head of the Department of Physics & Space Sciences and Associate Provost for Research at the Florida Institute of Technology.