(Apr 2024) Cool Star Lab PI Adam Burgasser led a cruise expedition on board the Holland America Koningsdam to view the total solar eclipse off the coast of Mexico. The crew were met with clear skies and over 4 minutes of totality! Adam also held several outreach talks on brown dwarfs, searches for life, and exciting results from JWST. See some of the media coverage at USA Today, Fox 5 San Diego, and ABC 10 San Diego.

(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...)

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!

(April 2024) Adam Burgasser contributed to analysis of the host star of the newly-discovered mini-Neptune exoplanet TOI-4336A b. The star is part of a hierarchical M dwarf triple system with nearly identical masses, mirroring the alien host star system in the Three Body Problem. The planet, which is about twice the size of Earth and receives 50% more light than Earth, is a promising target for transmission spectroscopy of a habitable zone world (read the preprint by Timmermans et al.)

(April 2024) Cool Star Lab members contributed to a detailed census of the local Solar Neighborhood. The volume-limited census of about 3600 individual objects, including components of multiple systems, extends from giant "planets" (≈ 5 Jupiter masses) to massive stars (≈8 solar masses). This comprehensive study reports the most accurate measurement of the stellar initial mass function to date, and finds that roughly 20% of all "stars" are substellar brown dwarfs. (read the ApJS article by Kirkpatrick et al.)

(March 2024) 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.)

(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)

(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 ApJ paper by Gerasimov et al.)

(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]