(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. 

(May 2024) Research led by Cool Star alum Roman Gerasimov was featured on the cover of the May 2024 edition of Astronomische Nachrichten! The cover shows the remarkable color-magnitude diagram of stars and white dwarfs in the globular cluster NGC 6752, based on HST data, and appears in Scalco et al. (2024). Roman computed the stellar models that accurately encompass the low mass stars in the upper right portion of the figure.

(May 2024) Cool Star Lab PI Adam Burgasser was awarded a UCSD Graduate and Professional Student Association Outstanding Faculty Teaching award! This annual award honors a faculty member at UCSD who is an exceptional educator at the graduate and/or professional level. Adam was nominated by Physics graduate student Thomas Wong. Congratulations Adam!

(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 preprint 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.)

(November 2024) Two new studies have probed the lowest-luminosity sources in three ancient globular clusters. Libralato et al. (2024) combined existing HST and new JWST observations of NGC 6121 and NGC 6397 to find that the lowest-mass members are more metal-rich and oxygen-poor than higher-mass stars, drawing on new evolutionary and atmosphere models generated by former CSL graduate student Roman Gerasimov. Scalco et al. (2024) explored the entirety of the white dwarf cooling sequence in Omega Centauri down to V ≈ 31 mag, finding the distribution is consistent with either a single-age population or one spread out over 5 billion years. Both studies capitalize on the incredible sensitivity, resolution, and multi-epoch astrometry from the two space telescopes (read the articles by Libralato et al. and Scalco et al. in Astronomy & Astrophysics).

(November 2024) NAU undergraduate Hunter Brooks and members of the Backyard Worlds: Planet 9 team have uncovered a swarm of ultracool stars and brown dwarfs using machine learning tools. The team used the SMDET neural network code developed by citizen scientist Dan Caselden to find 118 new low-temperature sources in a combination of PanSTARRS, UKIDSS, VISTA, and WISE/CATWISE survey data, and confirmed two objects as new T dwarfs with SpeX infrared spectroscopy. This work paves the way for larger samples constructed and characterized using deep multi-band survey data (read the article in the Astronomical Journal by Brooks et al.) 

(October 2024) One of the first known brown dwarfs and prototype T dwarf Gliese 229B has been resolved to be a binary system. Research led by Caltech graduate student Jerry Xuan combined high angular resolution observations with the Very Large Telescope Interferometer (VLTI) GRAVITY instrument with high spectral resolution observations with CRIRES to resolve the short period (12-day) orbit of its nearly equal-mass components (37 and 34 Jupiter masses). The discovery that Gliese 229B (now Gliese 229Bab) is a binary resolves many issues related to its mass and luminosity, and suggests the existence of other tight brown dwarf binaries yet to be identified (read the article in Nature by Xuan et al. and various press releases).

(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) 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.

(November 2024) CSL undergraduates Madison Fierro & Marylin Loritsch, graduate student Emma Softich, and CSL Director Adam Burgasser visited Lick Observatory to conduct observations with the Kast spectrograph. Although the run was sadly weathered out, the team was treated to an in-depth look at the 65-year old Shane 3m telescope and the innards of the Kast spectrograph by telescope operator Paul Canton, explored the space under the telescope floor, and played with the PANOSETI optics. Even a cloudy night can be educational!

(August 2024) CSL undergraduates took the 2024 UCSD Summer Undergraduate Research Conference by storm, with 13 presentations, including eight by the first STARTastro scholar cohort. The presented work spanned cool stars near the Sun to the detection of the most explosive events in the gamma rays. The summer conference capped an exciting summer of research. Some of the presentations can be found at this video, this video, or this video. Congratulations to our undergraduates on their successful research presentations! 

(August 2024) Members of the Cool Star Lab participated in the UCSD Astronomy & Astrophysics booth at the 4th Southeast Art & Science Expo at Malcolm X library in San Diego. This community event engages people of all ages in science, art, technology and exploration. Our booth featured demonstrations on optics, representations of the electromagnetic spectrum, tactile "images" of cosmic sources, and an opportunity to see the sunspots on our currently highly active Sun. 

(July 2024) The first STARTastro scholars have begun their summer program at UCSD! STARTastro, funded by the Heising Simons Foundation, is led by Adam Burgasser and Karin Sandstrom at UCSD, and Kate Rubin at SDSU, and aims to support community college transfer students bridge into their UC astronomy/physics/etc. majors. The STARTastro scholars hail from 6 CCs in San Diego, Orange, and LA counties, and will embark on an 8-week program of academic and professional development and research.