Planetary Science Directorate

SOUTHWEST RESEARCH INSTITUTE, BOULDER OFFICE

Upcoming SwRI Boulder Colloquia

Colloquia are normally on Tuesdays at 11:00 am in the 4th-floor conference room, except as indicated below in bold text.
Show previous colloquia
Suggest a New Speaker

For questions or suggestions for speakers, please contact the SwRI colloquium organizers:
Raluca Rufu, 303-226-0879 or raluca(at)boulder.swri.edu
Julien Salmon, 720-208-7203 or julien(at)boulder.swri.edu
Kelsi Singer, 303-226-5910 or ksinger(at)boulder.swri.edu
Sierra Ferguson, sierra.ferguson(at)swri.org
Rogerio Deienno, rogerio.deienno(at)swri.org
Sam Van Kooten, 303-226-5909 or svankooten(at)boulder.swri.edu

To be added to the SwRI Boulder Colloquia email list, please contact Kelsi Singer, ksinger(at)boulder.swri.edu

Suggest a New Speaker HERE
Tue Apr 16, 2024
In CR5+webex
11:00 am Sean Raymond Laboratoire d'Astrophysique de Bordeaux Orbital trajectories of the Solar System including stellar flybys: paleoclimate, chaos, and potential system disruption
Due to our move, this colloquium talk may potentially be transferred to the Amenity Center Conference room at the Canyon Center at 9th and Walnut.
Abstract: The Sun continually undergoes flybys with other stars as it orbits within the Milky Way. I will present simulations of the dynamical effect of stellar passages in two different contexts. First, I will show how close-passing field stars alter our entire planetary system's orbital evolution via their gravitational perturbations on the giant planets (Kaib & Raymond 2024). This shortens the timespan over which Earth's orbital evolution can be definitively known by a further ~10% compared with the planets in isolation. In simulations that include an exceptionally close passage of the Sun-like star HD 7977 2.8 Myr ago, new sequences of Earth's orbital evolution become possible in epochs before ~50 Myr ago, which includes the Paleocene–Eocene Thermal Maximum. Thus, simulations predicting Earth's past orbital evolution before ~50 Myr ago must consider the additional uncertainty from passing stars, which can open new regimes of past orbital evolution not seen in previous modeling efforts. Second, I will present the extreme case of a stellar passage within 100 au of the Sun, which has a 1% probability of happening per Gyr. In some cases, such a close stellar passage can disrupt the Solar System, by directly perturbing the planets' orbits or by triggering a dynamical instability. The most probable destructive pathways for Earth are to undergo a giant impact (with the Moon or Venus) or to collide with the Sun. Each planet may find itself on a very different orbit than its present-day one, in some cases with high eccentricities or inclinations. There is a small chance that Earth could end up on a more distant (colder) orbit, through re-shuffling of the system's orbital architecture, ejection into interstellar space (or into the Oort cloud), or capture by the passing star.
Tue Apr 23, 2024
In CR5+webex
11:00 am Adolfo Carvalho California Institute of Technology How FU Ori-type Accretion Outbursts Can Alter the Planet-Forming Environment of the Inner Disk
Due to our move, this colloquium talk may potentially be transferred to the Amenity Center Conference room at the Canyon Center at 9th and Walnut.
Tue Apr 30, 2024
In CR5+webex
11:00 am Andy López-Oquendo Northern Arizona University TBD
Due to our move, this colloquium talk may potentially be transferred to the Amenity Center Conference room at the Canyon Center at 9th and Walnut.
Thu Aug 22, 202411:00 am Barbara Thompson NASA Goddard Next generation communication challenges