(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!

(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). 

(April 2025) Cool Star Lab members were featured in a recent photo essay on the 2025 Conferences for Undergraduate Women and Gender Minorities in Physics (CU*IP) hosted by UCSD in January (see the photo essay on UC San Diego Today).

(August 2024) Our speedy little star was featured in the New York Times! NYT Science Reporter Katrina Miller highlighted the contributions of citizen scientists like Tom Bickle who was one of three amateur astronomers to identify the source as part of the Backyard Worlds: Planet 9 project.

(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.)

(September 2025) Cool Star Lab members helped to characterize the host stars of four new Super-Earth and Warm Neptune worlds uncovered by the TESS survey and confirmed by ground-based SPECULOOS monitoring. The stars were characterized using the Lick Observatory Shane 3m Kast Double spectrograph and the Magellan Observatory Baade 6.5m MagE spectrograph, and found to be M0-M4 dwarfs with a range of metallicities. The planets have masses of 4x to 26x the mass of Earth, with one super-Earth (TOI-5799c) being on the inner edge of its star's habitable zone. The planets continue to fill in gaps in the radius/period distribution of exoplanets, including a new "Neptunian ridge (read the preprint by Yalçınkaya et al.).

(September 2025) Cool Star Lab researchers have contributed to the first detection of silane (SiH4) in an extrasolar world with JWST. The world is named WISEA J153429.75-104303.3, or more colloquially "The Accident", and is a very metal-poor and low-temperature brown dwarf that is likely the lowest-mass member of the Galactic halo currently known. The detection of silane gas provides a unique window into silicon chemistry in low-temperature atmospheres, in particular the formation silicate condensates present in warmer L-type brown dwarfs. The study was led by Dr. Jackie Faherty, an alumna of the Cool Star Lab (see the Nature article by Faherty et al.)

(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. The system, named UPM J1040−3551 AabBab, was discovered by collaborator Prof. Zenghua Zhang at Nanjing University, and appears on the sky as a wide M dwarf + T dwarf pair. However, closer scrutiny reveals both components to be overluminous, are likely 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.).

(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!

(August 2025) Research scholars Alejandra Reynoso Olachea and Victor Daniel Rameriz Soto presented their summer research project at the 2025 ENLACE Symposium. The scholars, both from Mexico, joined the Cool Star Lab through the ENLACE program, a bi-national program that encourages the participation of high school and university students in research in STEM, while promoting cross-border friendships between Latin America and the United States. Alejandra & Victor presented their work reducing and analyzing the infrared spectra of supernovae from the IRTF/SpeX archive, and were co-mentored by graduate student Emma Softich. Congratulations on a successful summer Alejandra & Victor! 

(June 2025) Cool Star Lab members Adam Burgasser and Emma Softich presented research at the 246th American Astronomical Society meeting in Anchorage, AL. Adam gave a talk about the detection of strong phosphine in the atmosphere of Wolf 1130C, and a poster about the SpeX Spectral Archive. Emma presented her work on moderate-resolution FIRE spectra of T-type brown dwarfs. Former CSL members Dino Hsu and Aishwarya Iyer also presented, as well as Kielan Hoch who led a press conference.

(May 2025) Cool Star Lab undergraduate researcher Kongcheng Liu has been inducted into the into Phi Beta Kappa National Honor Society. Phi Beta Kappa was founded in 1776, and is the oldest academic society in the US. Nominees represent no more than 10% of the student population, and requires a minimum GPA of 3.85, a broad academic curriculum, and completion of a foreign language. Congratulations Kongcheng!