UC San Diego Cool Star Lab

Welcome to the homepage of the UC San Diego Cool Star Lab! Feel free to use the links below to learn about our research, teaching, and community activities, and meet our present and past members.

In the News

(Jan 2024) Cool Star Lab undergraduate Tiffany Liou was awarded a Chambliss Astronomy Achievement Student Award at the AAS 243 Winter Meeting in New Orleans, LA. The Chambliss awards recognize exemplary research by undergraduate and graduate students who present at one of the poster sessions at the AAS meetings, and are honored with a Chambliss medal. Tiffany earned her Chambliss from her presentation "Rest-UV Properties of MUSE DR2 Galaxies". Congratulations Tiffany! [read more at AAS...]

(Oct 2024) Cool Star Lab members Bretton Simpson, Joman Wong, and Adam Burgasser led an outreach event on the Holland America cruise ship Volendam while it was in port, introducing 6th grade students from the Perkins school in Barrio Logan to the upcoming October 14th annular solar eclipse. The students got to "stare at the Sun" through eclipse glasses and their own homemade solar pinhole projection box [see the news coverage on CBS8]

(Sep 2023) The Cool Star Lab is remembering Prof. Laura Quaynor, a research collaborator on graduate reading skill development. Dr. Quaynor was department chair of Advanced Studies in Education at Johns Hopkins University and one of the lead authors of the CERIC method. Dr. Quaynor will be remembered as a kind and effective mentor, and a valued colleague. We share our grief and condolences with her family (read more...).

Adam Burgasser has been inducted into the UCSD Athletics Hall of Fame. Adam was a NCAA Division III National Champion diver at UCSD, and received NCAA's Diver of the Year, Top VIII Scholar-Athlete, and  Silver Anniversary awards. (read more...)

Adam Burgasser will be leading an eclipse viewing from a cruise ship next year! The April 2024 "Eclipse America" will pass across Mexico and the US, and Adam will be helping sea voyagers on Holland America get the best view (read more.. and also the AAS Eclipse page).

Christopher Theissen has accepted a position as Assistant Professor in the new Department of Astronomy & Astrophysics. He is the first hire to be made in the Department, and will be leading work on mining large astronomical datasets. Welcome Prof. Theissen!

Research Highlights

(March 2024) Former Cool Star Lab graduate Dino Hsu has published a study of radial and rotational velocities of late-M and L dwarfs observed with the SDSS/APOGEE instrument. The high spectral resolution of APOGEE combined with a forward-modeling approach results in radial velocity precisions of 400 m/s. The study identified 3 new members of young moving groups, and 37 sources with significant radial velocity variations, including binaries with orbital periods measured in days. It also found an expected decline in radius (inferred from rotational velocity and variability period) with age. (read the preprint by Hsu et al.)

(March 2024) Cool Star Lab members contributed to a massive haul of benchmark ultracool dwarf companions to nearby stars identified by the Backyard Worlds Team. CUNY graduate student Austin Rothermich identified 89 new systems with G2-M9 primaries and M7-T9 companions with diverse spectral properties, and many of these systems appear to be triples and quadruples. These systems span exceptionally wide separations and low mass ratios, in the latter case with similar values as exoplanet systems.  (read the preprint by Rothermich et al. and watch his AAS 243 press conference)

(March 2023) Former Cool Star Lab graduate Roman Gerasimov contributed a new set of spectral and evolutionary models to accurately characterize the three distinct stellar populations of the NGC 6752 globular cluster imaged by HST. Roman's modeling framework spanning the entirety of the Main Sequence was able to show that these populations can be accurately modeled by varying sodium, carbon, oxygen, and aluminum abundances, and further show distinct luminosity functions that could be explained by dynamical scattering. (read the preprint by Scalco et al.)

(Jan 2024) current and former Cool Star Lab members were out in full force at AAS 243 Winter meeting in New Orleans, LA, presenting research spanning a broad range of science, art, education and community issues. Presentations included: 

Adam Burgasser also co-led a booth on the Sound Planetarium project with Tara Knight and participated in a panel discussion on effective partnerships with HBCUs; Genevive Bjorn and Dino Hsu led a workshop on the CERIC method; and CLS alumna Jackie Faherty and her colleagues were featured in a press conference. Undergraduate past/present members Hunter Brooks, Malina Desai, Juan Diego Draxl Giannoni, Tiffany Liou, and Brigette Vazquez-Segovia also presented, with Tiffany Liou winning a Chambliss Award

In the Community

(Jan 2024) Cool Star Lab members participated in the Southern California Workshop for Cal-Bridge Scholars, hosted at UCSD. In addition to running lab tours for visiting Scholars, Genevive Bjorn & Adam Burgasser led a 3-hour workshop on the CERIC method for reading the primary literature.

(Jan 2024) Members of the UCSD Astronomy & Astrophysics and Physics community participated in the 2024 CUWIP conference, hosted regionally by the University of San Diego. Faculty and students participated in discussion panels, workshops, and graduate program information sessions. UCSD is gearing up to host the 2025 CU*IP conference in January 2025!

(Nov 2023) Adam Burgasser joined UCSD community members to share lunch with members of the crew of the Hōkūleʻa, an event hosted by the Birch Aquarium and the Polynesian Voyaging Society. This famous Polynesian traditional voyaging vessel, or wa'a, was ending its first leg of the Moananuiākea voyage before going back to Hawai'i.

(Oct 2023) UCSD Astronomy & Astrophsyics students, faculty, and researchers came out to celebrate and educate the partial eclipse of the Sun on October 14th at the Fleet Museum at Balboa Park. We brought various telescopes for viewing and projecting the eclipse for several hundred community members, some of whom got to hold the crescent Sun in their hands! [see the news coverage...]

Adam Burgasser welcomed IR astronomy colleague and Physics PhD alum Bill Forrest (1974) back to UCSD for his 50th reunion. Bill leads work on infrared detector technologies and studies dust, the ISM, and brown dwarfs. In addition to visiting the Physics and Astronomy & Astrophysics Departments, Bill got to check in on his favorite haunt, the Che Cafe (formerly the Coffee Hut), where his band Soledad Mountain Ramblers played, and he shared a recording of a concert his band played there in 1970 with Che Cafe staff. Bill organized the UCSD Mini Folk Fest in the early 1970s at the "Grassy Knoll", still located just east of the Main Gym [listen to Soledad Mountain Ramblers at the Coffee Hut, 1970

Cool Star Lab members Bretton Simpson, Joman Wong, and Adam Burgasser led an outreach event on the Holland America cruise ship Volendam while it was in port, introducing 6th grade students from the Perkins school in Barrio Logan to the upcoming October 14th annular solar eclipse. The students got to "stare at the Sun" through eclipse glasses and their own homemade solar pinhole projection box [see the news coverage on CBS8]