(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).
(February 2025) Cool Star Lab members were featured in a recent photo essay on Lick Observatory, during a visit on site in October 2024. Stunning photographs of the facility were taken by photographer Erik Jepsen, and feature some inside views of the observatory's inner workings (see the photo essay on UC San Diego Today).
(February 2025) The discovery of a potential fifth component to the Regulus system recently reported by Eric Mamajek and Adam Burgasser in the Astronomical Journal has been featured on AAS's Nova site! Nova curates the most interesting recent results published in AAS journals, providing astronomy researchers and enthusiasts summaries of recent research across a wide range of astronomical fields (read the Nova article: https://aasnova.org/2025/02/05/a-new-groupie-in-regulus-entourage/).
(January 2025) Cool Star Lab undergraduate researchers Marylin Loritsch and Tianxing "Sky" Zhou have received the prestigious American Astronomical Society Chambliss Astronomy Achievement Student Awards! The Chambliss Awards recognize exemplary research by undergraduate and graduate students who present a poster session at the AAS national meeting. Awardees are honored with a Chambliss medal. Marylin received her award for her presentation "Characterizing the Optical Spectra of the Nearest Stellar Neighbors: The 20 Parsec Sample". Tianxing received his award for his presentation "Cool Stars, Hot Tech: Spectral Typing of M, L, and T Dwarfs with Machine Learning" Congratulations to our award-winning undergraduates! (see the press announcement from the AAS).
(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.
(May 2025) Cool Star Lab PI Adam Burgasser partnered with U. Bern graduate student Anna Lueber to investigate machine learning approaches to modeling brown dwarf spectra. They compared the traditional "best fit" approach using the Monte Carlo Markov Chain (MCMC) algorithm to a machine learning algorithm know as Random Forest Retrievals that uses decision trees to determine best fit parameters. The study found that the MCMC approach yields betters fits and parameter constraints, while the RFR approach yields similar parameters and is considerably faster. The study proposes combining these methods for efficient exploration of multiple sets of models (read the preprint by Lueber & Burgasser.).
(May 2025) Cool Star Lab undergraduate Marylin Loritsch has led a Research Note characterizing the optical spectra of low-mass stars within 20 pc of the Sun, many of which have not been previously classified. Marylin measured spectral types, metallicity indices, and H-alpha emission, and also identified a previously unrecognized low-mass binary system LP 546-37. Marylin conducted this research as part of the STARTastro program (read the Research Note by Loritsch et al. 2025).
(April 2025) The Cool Star Lab contributed Kast optical spectra to help characterize a remarkable cold exoplanet system containing a pair of old and low-mass stars. TOI-6478b is a Neptune-like planet about 10 times more massive than the Earth. It orbits the lower-mass member of a M dwarf binary system whose motion through the Milky Way indicates it is an old member of the Galaxy's thick disk population. Measurement of the mass and radius of the planet indicates that it has a thick atmosphere whose chemical composition could be easily measured with JWST (read the MNRAS article by Madison et al.).
(March 2025) Cool Star Lab members welcomed the first ultracool dwarf datasets from Euclid by contributing to a series of papers from the surveys first quicklook data release (Q1). Zerjal et al. (2025) reports the photometric selection of over 1000 L and T dwarfs in 63 deg2 of deep photometric data, predicting >105 such sources in the final survey. Dominguez-Tagle et al. (2025) present the first analysis of Euclid spectra of ultracoo dwarfs, enabling the template sequence shown above. Both studies were facilitated by SpeX templates provided in the SpeX Prism Library Analysis Toolkit (SPLAT). Euclid will be a major discovery machine for brown dwarfs across the Galaxy over the next few years (read the preprints by Zerjal et al. and Dominguez-Tagle et al.).
(February 2025) Cool Star Lab members contributed to a study of the metallicity distribution of planet-hosting M dwarfs, using near-infrared spectra collected with IRTF/SpeX. The sample of 22 M dwarfs hosting giant planets is distinctly metal-rich compared to the overall M dwarf population, aligning with prior studies showing that gas giants are typically found around more massive metal-rich stars. There was no difference in metallicity between M dwarfs hosting "hot" and "warm" Jupiters (read the ApJS paper by Gan et al.).
(March 2024) The JWST Cycle 1 program GO-2473 has released its survey of Y dwarf photometry at 1.5 µm and 4.8 µm, the deepest collection of low-temperature brown dwarf brightness measurements to date. One source, WISE J1047+5457 appears to be unusually blue and may be a young, planetary mass brown dwarf; the secondary of the WISE J0336-0143AB system has a temperature below 300 K (23 ºC) making it the second coldest brown dwarf yet detected (read the AJ article by Albert et al.).
(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!
(May 2025) Cool Star Lab graduate researcher Emma Softich Is official a PhD candidate! Emma successfully passed her candidacy exam with her intended thesis project aiming to improve modeling of JWST spectra of brown dwarfs. Congratulations Emma!
(April 2025) Cool Star Lab member Marylin Loritsch was one of five STARTastro scholars selected to receive Summer Program for Undergraduate Research in Science (SPURS) funding for the upcoming summer. SPURS is a competitive program that supports students in a 10-week summer research project under the guidance of a UCSD faculty member. Marylin will be building on her work analyzing the optical spectra of planet host stars obtained with the Shane/Kast spectrograph. Congratulations Marylin!
(April 2025) Current and former members of the Cool Star Lab participated in the 2025 Barrio Logan Science and Art Festival. Organized by the Barrio Logan Association, UCSD CREATE, and community partners, this festival highlights science, art and culture across San Diego communities. We participated as part of a table hosted by the Department of Astronomy & Astrophysics, which featured astronomy demonstrations (including an opportunity to "stare at the Sun", and students created a solar system that spanned the festival. Adam Burgasser was even featured in local news coverage of the event.
(April 2025) Cool Star Lab undergraduate researcher Sara Morrissey has received two prestigious awards: the Physical Sciences Dean's Undergraduate Award for Excellence and the Selma and Robert Silagi Award. The Dean's Award "recognizes students who have demonstrated academic excellence and promise as researchers", while the Silagi award is presented to an outstanding senior in the natural sciences and honors the memory of Dr. Selma Silagi who made important discoveries on the molecular basis of melanoma tumor formation. Congratulations Sarah!
(February 2025) Applications are now open for the second cohort of the STARTastro program. STARTastro is a regional partnership between UC San Diego, San Diego State University, and Southern California's minority-serving community colleges that aims to support transfer student success for Astronomy and physical science majors through a Transfer Receptive Culture Model. STARTastro provides academic and research preparation during the summer, helping transfer students be ready to excel as upper division majors. The program is open to all public California Community College students who are transferring into a STEM major at UCSD, SDSU, or other UC/CSU programs. Hurry, applications close April 15 for CSU students and May 15 for UC students!
UCSD was one of 15 hosts sites for this year's Conferences for Undergraduate Women and Gender Minorities in Physics (CU*IP), organized nationally by the American Physical Society (APS). Co-organized by the Departments of Astronomy & Astrophysics and Physics, with co-Chairs Javier Duarte, Tongyan Lin, Adam Burgasser, and Robin Glefke, CU*IP@UCSD brought nearly 200 students from the southwest US, Hawaii, and (for the first time!) Mexico to a weekend of plenary talks (including one of UCSD's newest faculty members Floor Broekgaarden), workshops, and poster presentations. Cool Star Lab members Adam Burgasser and Sara Morrissey (who serves as Vice-President of UCSD's Society of Physics Students chapter) both helped to organize the meeting; Adam led two panels on Physics and Academia and served on an Education panel; and Sara, Madison Fierro, and Marylin Loritsch each presented posters at the conference. Marylin's poster received a conference prize for best poster on Stars and Stellar Populations! Congratulations to the conference team and the research presenters!
You can see all the conference posters, including those by Sara, Madison, and Marylin, at the conference poster webpage. The School of Physical Sciences also featured the conference in a photo essay.