(October 2025) Cool Star Lab researcher Marylin Loritsch has been awarded a USRA Distinguished Undergraduate Award Honorable Mention. USRA is an independent, nonprofit research corporation that advances space science and technology through industry, government, and university partnerships; UCSD is one of 121 participating universities. The annual USRA Award recognizes undergraduate students with a career interest in space science or engineering with a distinguished academic and research portfolio. Marylin's Honorable Mention recognizes her as among the top 10% of this year's applicant pool. Congratulations Marylin!

(October 2025) Cool Star Lab PI Adam Burgasser led a study in Science reporting the detection of abundant phosphine in the atmosphere of a cold brown dwarf named Wolf 1130C. Based on JWST observations, the study would phosphine at the level expected for vertical mixing chemistry, and reverses the pattern of "missing phosphine" in other brown dwarf and exoplanet atmospheres, and raises new questions about our understanding of phosphorous chemistry. The result was the subject of a press release and reported widely in the New York Times, the Conversation, and other venues (see the UCSD press release and the published Science article)

(August 2025) Cool Star Lab PI Adam Burgasser led spectral analysis of a rare "double-double" system composed of low-mass stars and brown dwarfs. Discovered by collaborator Prof. Zenghua Zhang at Nanjing University, the system is named UPM J1040−3551 AabBab and appears on the sky as a wide M dwarf + T dwarf binary. However, closer scrutiny reveals both components to be overluminous, are likely both comprised of two objects each in close orbits. This discovery adds new empirical insight into how low-mass multiple star systems form, and received wide press coverage including a story in the New York Times Science Section (read the MNRAS article by Zhang et al.).

(August 2025) Holland America has announced that Cool Star PI Adam Burgasser will be part of the line-up for its “Mediterranean Solar Eclipse” cruise on the Oosterdam as its catches the total solar eclipse on August 12, 2026. Adam had previously served as "ship astronomer" during the April 2024 eclipse off the coast of Mexico. All Aboard! (read the Holland America press release)

(April 2025) Cool Star Lab PI Adam Burgasser was featured in local news coverage of the n the 2025 Barrio Logan Science and Art Festival. Members of the Department of Astronomy & Astrophysics hosted a booth at the event which featured astronomy demonstrations – including an opportunity to "stare at the Sun" –  and students created a solar system that spanned the festival (see the full NBC 7 San Diego coverage). 

(January 2025) Cool Star Lab graduate researcher Julia Haynes was featured in an article in the San Diego Tribune, highlighting her excellence in tennis and aspirations in astrophysics. Julia is the first nationally-ranked tennis player at UC San Diego since it joined Division I, and joined the team after completing her astrophysics degree at Columbia University. Now Julia is working on finding brown dwarfs in JWST deep survey fields using machine learning tools she's developing in the UCSD Data Science Masters program (see the San Diego Tribune story).

(December 2025) Cool Star Lab used observations obtained with the Shane 3m Kast spectrograph to characterize the host star of a newly-discovered habitable zone mini-Neptune exoplanet. The host star TOI-7166 is an mildly active M4.5 dwarf near the mass threshold for fully convective interiors. SPECULOOS transit observations show that the planet TOI-7166b is twice the size of Earth and on a 13-day orbit, and receives almost exactly the same flux from its star as Earth receives from the Sun. The source is a prime target for future atmospheric characterization with JWST (read the MNRAS article by Barkaoui et al.).

(November 2025) Recent UCSD graduate Sara Morrissey has reported the findings of her Honors thesis, the discovery of 7 distant L and T dwarfs in deep JWST spectroscopy by the RUBIES survey. Sara used the 1-5 µm spectra to classify her discoveries and determine their temperatures, metallicities, and distances, the last reaching out to 3,000 pc from the Sun. Two of the sources show evidence of being metal-poor brown dwarfs. Congratulations on your first peer-reviewed article Sara! (see the preprint by Morrissey et al.)

(November 2025) South Pasadena high school researcher Wings Zhang reported the discovery of over 100 new high proper stars detected in the UKIRT Hemisphere Survey (UHS), as part of the Backyard Worlds collaboration. Shane 3m Kast spectroscopy obtained by Cool Star Lab members confirmed two sources as metal-poor M subdwarfs 100-200 pc from the Sun, and color and absolute magnitude measurements indicate these sources encompass a wide range of previously unknown, ancient metal-poor low-mass stars (see the AJ article by Zhang et al.).

(October 2025) Observations conducted by Cool Star Lab members with the Shane 3m Kast spectrograph have contributed to the discovery and characterization of five new massive exoplanets orbiting low-mass stars. All fives planets are Jovian-sized worlds orbiting low-mass, early M dwarfs, a rare configuration in current exoplanet surveys. Two of the stellar systems are also binaries. This is the second study in a series called MANGOS (M dwarfs Accompanied by close-iN Giant Orbiters with SPECULOOS; read the preprint by Dransfield & Timmermans et al.).

(October 2025) Cool Star Lab PI Adam Burgasser reported the detection of abundant phosphine in the atmosphere of a cold brown dwarf named Wolf 1130C, based on JWST observations obtained as part of the Arcana of the Ancients program. The detection of phosphine, measured by co-author Dr. Eileen Gonzales to at the 100 ppb level, reverses the pattern of "missing phosphine" in other brown dwarf and exoplanet atmospheres, and raises new questions about our understanding of phosphorous chemistry. The result was widely reported in the press (see the Science article and preprint by Burgasser et al.)

(September 2025) Cool Star Lab undergraduate researcher Tianxing Zhou has led a new study investigating machine learning classification methods for low-temperature dwarfs. Drawing on a set of low-resolution near-infrared spectra from the SPLAT archive, Tianxing explored multiple ML models, and found that a k-nearest neighbors algorithm was able to classify 96% of sources to with one subtype and assign gravity and metallicity classifications with 90% accuracy. Tianxing's work advances tools for studying large samples of spectra now emerging from space telescopes such as Euclid and JWST (see the ApJ article by Zhou et al.)

(November 2025) Cool Star Lab PI Adam Burgasser presented the latest results obtained with JWST at the Mira Astronomy Club Quarterly Meeting, highlighting amazing images and measurements from the Solar System to the most distance galaxies (see the slide deck). 

(October 2025) Cool Star Lab PI Adam Burgasser participated in an Astrophysics Panel hosted by UCSD's Society of Asian Science and Engineers (SASE).  Adam, faculty Brian Keating and Ethan Nadler, and postdoctoral scholar Julie Inglis shared their experiences on becoming astrophysicists, and how to pursue research opportunities in the field.

(October 2025) Cool Star Lab PI Adam Burgasser shared his experience using the Palomar Observatory as a graduate student as part of Fleet Science's Sky Tonight: Palomar Observatory Experience.  Adam also updated the group on current results in brown dwarf astrophysics. The next Palomar Experience is April 2026 (see the slide deck).

(September 2025) Cool Star Lab members are volunteering in the Cosmic Tours program, an outreach project that brings a portable planetarium to local K-12 schools and community sites. The inflatable planetarium provides an interactive astronomical experience of the night sky, including a tour of constellations in different cultures and a tour of the Solar System. Since its founding, Cosmic Tours has held 150 events across the San Diego region (read more about Cosmic Tours, including how to support and coordinate an event at your institution)

(August 2025) STARTastro scholar Ethan Baker and PI Adam Burgasser facilitated a star party in the Anza Borrego desert with students and community members of Kumeyaay Community College. The event was part of a teaching Kumeyaay cosmology course led by tribal elder Michael Connolly Miskwish, author of Maay Uuyow: Kumeyaay Cosmology. The dark moonless skies afforded beautiful views of the Milky Way (Hatotkeur); the constellations Scorpius (Shuluk), Cassiopaeia (Llykuushirra), and the Big Dipper (Shallymat); Mars and Saturn; and various star clusters and the Andromeda Galaxy.

(August 2025) Cool Star Lab undergraduates Madison Fierro, Marylin Loritsch, and Evan Pritchard were among 20 STARTastro scholars who presented at the 2025 UCSD Summer Research Conference. Madison presented her work on new ultracool dwarf spectra from the IRFT/SpeX archive, and Marylin and Evan presented their discovery and characterization of distant brown dwarfs from JWST spectroscopic surveys. Graduate student Emma Softich co-mentored all three projects. Congratulations to our research scholars!