(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.

(July 2024) Comic Con 2024 has come to San Diego! Cool Star Lab PI Adam Burgasser participated in a panel discussion on the TV series For All Mankind: Historic Fiction, Real Science with several experts in space science, engineering, biology, and sociology. The panel was hosted by the Fleet Center's Andrea Decker. Read how several UCSD folks contributed to Comic Con, and watch the For All Mankind panel discussion on YouTube.

(July 2024) The discovery of a hot Earth-sized planet orbiting the M-type star SPECULOOS-3, reported by Gillon et al. (2024), has been featured on the cover of Nature Astronomy!  Read the paper by Gillon et al. (2024) and the press release by UCSD Physical Sciences.

(June 2024) Research led by Adam Burgasser and Roman Gerasimov were both featured in press conferences at the AAS 244 meeting in Madison, Wisconsin. Adam reported the discovery of a remarkably fast-moving, metal-poor L dwarf uncovered by citizen scientists that may be on its way to escaping the Milky Way. Roman reported the first discovery of brown dwarfs in JWST observations of the globular cluster NGC 6397. Learn more by watching the AAS 244 press conferences by Adam and Roman; you can also see some of the press images for the speedy L subdwarf in the UCSD Physical Science press release. 

(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.).

(February 2025) Observations by the Cool Star Lab team contributed to the characterization of two new exoplanets orbiting low-mass stars. TOI-2015 is an active M4 dwarf that contains at least two sub-Neptune mass planets, each about 9 Earth masses, in a 5:3 orbital resonance, with the inner planet lying near the radius-period "gap" observed among short-period exoplanets. The active M6 dwarf TOI-6508 has a far more massive "planet" companion of 75 Jupiter masses, at the star/brown dwarf limit, making this system more akin to a short period (19 day) low-mass binary system (read the preprints by Barkaoui et al on TOI-2015b and TOI-6508b).

(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.).

(December 2024) NASA JPL's Eric Mamajek and CSL PI Adam Burgasser have potentially identified a fifth member of the Regulus star system. The discovery, a previously known L/T transition object 2MASS J10071185+1930563 was observed with Keck/NIRES, and the source's radial velocity, distance and proper motion all align with Regulus, suggesting a physical connection or a common origin. Remarkably, the brown dwarf is 7.5 degrees away from Regulus, about 3.9 parsecs (12.6 lightyears) in projected distance, almost 3 times the separation of the Sun and its nearest stellar companion Proxima Centauri. Regulus, or alpha Leonis, is the brightest star in the constellation Leo, and is a binary star composed of a B subgiant and a white dwarf that may have interacted. The other two stars in the system, Regulus BC (aka HD 87884), are a K dwarf/M dwarf pair, making this an extremely wide hierarchical quintuple (read the AJ article by Mamajek & Burgasser)

(November 2024) The North ecliptic pole EXtragalactic Unified Survey (NEXUS) project, a Multi-Cycle JWST Treasuary program, released its first set of data, including NIRCam images and wide-field slitless spectroscopy over a 100 square arcminute area near the North Ecliptic Pole. This area aligns with the Euclid North Deep Field, promising multi-epoch deep imaging and spectroscopy over the next 4 years. The final data will encompass deep, multi-epoch NIRCam imaging and NIRSpec PRISM spectroscopy over 400 square arcminutes down to imaging depths of 28-29 mag in 6 infrared filters. In addition to thousands of high redshift galaxies, this survey is expected to uncover dozens of brown dwarfs at kpc scales (read the preprint by Zuang et al. and access the data at https://ariel.astro.illinois.edu/nexus/edr/).  

(November 2024) CSL PI Adam Burgasser and members of the Backyard Worlds: Planet 9 team have conducted a comprehensive study of metal-poor T dwarfs, including sources discovered by citizen scientists from multi-epoch WISE data. Selecting sources based on reduced proper motion, the team identified dozens of metal-poor objects, including three "extreme" cases. They also identified three metal-rich sources with thick disk kinematics, likely ejected from the inner Milky Way. 3D kinematics enabled by Keck/NIRES observations reveal that two sources may be part of the Thamnos population, and one source part of the Helmi stream. They study also made the first metallicity classification system for T (sub)dwarfs, and defined a metallicity index for near-infrared spectra. This work helps ongoing studies that are searching for thick-disk and halo brown dwarfs in deep JWST and Euclid fields (read the preprint by Burgasser et al.)

(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!

(February 2025) Members of the UCSD A&A community, including Cool Star Lab PI Adam Burgasser, participated in the San Diego Festival of Science & Engineering, held annually at Petco Park. Adam set up a mini to-scale Solar System in the park, requiring telescopes to view Jupiter and Saturn.  Jarred Roberts set up demonstrations on exoplanet transits and gravitational orbits & waves.  Over 20,000 attendees visited 150 exhibitors at the park.

(February 2025) UCSD A&A graduate student Vincent Savignac and Cool Star Lab PI Adam Burgasser and brought science to the people at an Astronomy on Tap event at the Duck Foot Brewing Miramar. Vincent led a discussion on the habitability of planets in the Stars Wars universe, while Adam talked about his team's recent discovery of a hypervelocity star. Astronomy on Tap is an international program that brings astronomical science to communities across the globe.

(December 2024) STARTastro scholars Annika Feng and Marylin Loritsch have been awarded the AAS FAMOUS Travel Grant for the upcoming AAS 245 meeting in Washington, DC. FAMOUS (Funds for Astronomical Meetings: Outreach to Underrepresented Scientists) grants award $1,000 for a single AAS meeting to present research, with priority given to members of historically underrepresented groups. Annika will be presenting her work on "Orbital Monitoring and Atmospheric Spectroscopy of the Directly Imaged Companion 1RXS J2351+3127 b" while Marylin will be presenting her work on "Characterizing the Optical Spectra of the Nearest Stellar Neighbors: The 20 Parsec Sample". Congratulations Annika & Marylin!

(November 2024) Emma Softich had the privilege of participating in the Girls Exploring Math and Science (GEMS), an outreach program associated with Keck Observatories. The November event included 16 workshops for over 150 5th-grade girls from the western part of the Big Island of Hawai'i. Emma helped present an exhibit on Infrared Astronomy which featured an interactive infrared camera, and shared the usefulness of infrared light when it comes to looking through dust - or trash bags! Emma really enjoyed the opportunity to interact with the students and help inspire the next generation of women in STEM.

(November 2024) CSL faculty Adam Burgasser  and Chris Theissen organized a departmental table for UCSD's Native American Heritage Month (NAHM) annual luncheon. This is the kickoff event to a month of workshops, presentations, and celebrations on the continued contributions of indigenous people to the greater San Diego community. This year's speaker, Dr. Cutcha Risling Baldy (Hupa, Karuk, and Yurok) spoke on Indigenous feminism, Traditional Ecological Knowledge, and decolonization.