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

(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

(Oct 2023) Recent Cool Star Lab graduate Roman Gerasimov has led a study investigating the lower Main Sequence of the globular cluster 47 Tucanae. Using a suite of low-temperature atmosphere models he computed, and a novel analysis method, Roman was able to explain the spread of the lower Main Sequence of the 47 Tucanae population in HST color-magnitude diagrams as arising in variations in Oxygen abundances, and was able to infer the distribution of Oxygen from photometry alone. He also inferred the luminosity and mass functions of the lowest mass stars in this ancient system (read the preprint by Gerasimov et al.)

(Oct 2023) Cool Star Lab members contributed to the discovery of a new Y dwarf identified by the Backyard Worlds Team. The source, CWISE J105512.11+544328.3, was confirmed and classified with Keck/NIRES near-infrared spectroscopy, and has an estimated temperature of 500 K. It's extremely blue mid-infrared suggests it may have an unusual, possibly metal-poor atmosphere. The publication was led by U. Florida undergraduate Grady Robbins (see the preprint by Robbins et al.)

(Oct 2023) Undergraduate researcher Alexia Bravo worked with collaborator Adam Schneider to analyze three peculiar brown dwarf spectra obtained as part of the Backyward Worlds project. She identified two spectral blend binaries and one potentially variable brown dwarf. The binaries may prove to be closely-separated systems for which mass measurements can be made, while the variable brown dwarf allows study of cloud formation and dynamics in low temperature atmospheres (see the preprint by Bravo et al. and the AAS Nova highlight)

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]