Calendar

Oct
5
Mon
Pizza Lunch: Tom Harrison
Oct 5 @ 12:30 pm – 1:30 pm
Pizza Lunch: Tom Harrison

V1500 Cyg and the Progenitors of SNIa

Dec
4
Fri
Colloquium: Brian Jackson
Dec 4 @ 3:15 pm – 4:15 pm
Colloquium:  Brian Jackson @ BX102

On the Edge: Exoplanets with Orbital Periods Shorter Than a Peter Jackson Movie

Brian Jackson, Boise State Univeristy

From wispy gas giants to tiny rocky bodies, exoplanets with orbital periods of several days and less challenge theories of planet formation and evolution. Recent searches have found small rocky planets with orbits reaching almost down to their host stars’ surfaces, including an iron-rich Mars-sized body with an orbital period of only four hours. So close to their host stars that some of them are actively disintegrating, these objects’ origins remain unclear, and even formation models that allow significant migration have trouble accounting for their very short periods. Some are members of multi-planet system and may have been driven inward via secular excitation and tidal damping by their sibling planets. Others may be the fossil cores of former gas giants whose atmospheres were stripped by tides.

In this presentation, I’ll discuss the work of our Short-Period Planets Group (SuPerPiG), focused on finding and understanding this surprising new class of exoplanets. We are sifting data from the reincarnated Kepler Mission, K2, to search for additional short-period planets and have found several new candidates. We are also modeling the tidal decay and disruption of close-in gaseous planets to determine how we could identify their remnants, and preliminary results suggest the cores have a distinctive mass-period relationship that may be apparent in the observed population. Whatever their origins, short-period planets are particularly amenable to discovery and detailed follow-up by ongoing and future surveys, including the TESS mission.

Apr
8
Fri
Colloquium PhD Defense: Meredith Rawls
Apr 8 @ 3:00 pm – 4:00 pm
Colloquium PhD Defense: Meredith Rawls @ BX102

Red Giants in Eclipsing Binaries as a Benchmark for Asteroseismology

Meredith Rawls, NMSU

Apr
15
Fri
Colloquium: Warren Skidmore (Host: Jim Murphy)
Apr 15 @ 3:15 pm – 4:15 pm
Colloquium:  Warren Skidmore     (Host: Jim Murphy) @ BX102

The Thirty Meter Telescope:   The Next Generation Ground Based Optical/InfraRed Observatory

Dr. Warren Skidmore, Thirty Meter Telescope Corp.

 

Abstract: After a construction status update, I will describe how the telescope design was developed to support a broad range of observing capabilities and how the observatory is being engineered. I’ll discuss some of the observational capabilities that the Thirty Meter Telescope will provide and some of the areas of study that will benefit from the TMT’s capabilities, specifically synergistic areas with new and future proposed astronomical facilities. Finally I will describe the avenues through which astronomers can have some input in the planning of the project and potential NSF partnership, prioritizing the development of 2nd generation instruments and directing the scientific aims for the observatory.

Mar
28
Tue
Joint Physics/Astronomy Colloquium: William Newman
Mar 28 @ 4:00 pm – 5:00 pm
Joint Physics/Astronomy Colloquium: William Newman @ Gardiner Hall 229, Physics. Dept. | Ames | Iowa | United States

Giant Planet Shielding of the Inner Solar System Revisited: Blending Celestial Mechanics with Advanced Computation

Dr. William Newman, UCLA

The Earth has sustained during the last billion years as many as five catastrophic collisions with asteroids and comets which led to widespread species extinctions. Our own atmosphere was literally blown away 4.5 billion years ago by a collision with a Mars-sized impactor. However, collisions with comets originating in the outer solar system accreted much of the present-day atmosphere. Relatively advanced life on our planet is the beneficiary of a number of impact events during Earth’s history which built our atmosphere without destroying a large fraction of terrestrial life. Using very high precision Monte Carlo integration methods to explore the orbital evolution over hundreds of millions of years followed by the application of celestial mechanical techniques, the presentation will explain directly how Earth was shielded by the combined influence of Jupiter and Saturn, assuring that only 1 in 100,000 potential collisions with the Earth will materialize.