The Astrophysical Journal (Jan 2025)
The UV Legacy Library of Young Stars as Essential Standards (ULLYSES) Large Director’s Discretionary Program with Hubble. I. Goals, Design, and Initial Results
- Julia Roman-Duval,
- William J. Fischer,
- Alexander W. Fullerton,
- Jo Taylor,
- Rachel Plesha,
- Charles Proffitt,
- TalaWanda Monroe,
- Travis C. Fischer,
- Alessandra Aloisi,
- Jean-Claude Bouret,
- Christopher Britt,
- Nuria Calvet,
- Joleen K. Carlberg,
- Paul A. Crowther,
- Gisella De Rosa,
- William V. Dixon,
- Catherine C. Espaillat,
- Christopher J. Evans,
- Andrew J. Fox,
- Kevin France,
- Miriam Garcia,
- Scott W. Fleming,
- Elaine M. Frazer,
- Ana I. Gómez de Castro,
- Gregory J. Herczeg,
- Svea Hernandez,
- Alec S. Hirschauer,
- Bethan L. James,
- Christopher M. Johns-Krull,
- Claus Leitherer,
- Sean Lockwood,
- Joan Najita,
- M. S. Oey,
- Cristina Oliveira,
- Tyler Pauly,
- I. Neill Reid,
- Adric Riedel,
- David R. Rodriguez,
- David Sahnow,
- Ravi Sankrit,
- Kenneth R. Sembach,
- Richard Shaw,
- Linda J. Smith,
- S. Tony Sohn,
- Debopam Som,
- Leonardo Úbeda,
- Daniel E. Welty
Affiliations
- Julia Roman-Duval
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- William J. Fischer
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Alexander W. Fullerton
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Jo Taylor
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Rachel Plesha
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Charles Proffitt
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- TalaWanda Monroe
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Travis C. Fischer
- ORCiD
- AURA for ESA , Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
- Alessandra Aloisi
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Jean-Claude Bouret
- ORCiD
- Aix-Marseille University , CNRS, CNES, LAM 13388 Marseille, France
- Christopher Britt
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Nuria Calvet
- ORCiD
- Department of Astronomy, University of Michigan , 1085 South University Avenue, Ann Arbor, MI 48109, USA
- Joleen K. Carlberg
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Paul A. Crowther
- ORCiD
- Department Physics & Astronomy Hounsfield Road, University of Sheffield , Sheffield S3 7RH, UK
- Gisella De Rosa
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- William V. Dixon
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Catherine C. Espaillat
- ORCiD
- Institute for Astrophysical Research, Department of Astronomy, Boston University , 725 Commonwealth Avenue, Boston, MA 02215, USA
- Christopher J. Evans
- ORCiD
- European Space Agency (ESA) , ESA Office, Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
- Andrew J. Fox
- ORCiD
- AURA for ESA , Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA; Department of Physics & Astronomy, Johns Hopkins University , 3400 N. Charles Street, Baltimore, MD 21218, USA
- Kevin France
- ORCiD
- Laboratory for Atmospheric and Space Physics, University of Colorado Boulder , Boulder, CO 80303, USA
- Miriam Garcia
- ORCiD
- Centro de Astrobiologia , CSIC-INTA, Dpto. de Astrofisica, Instituto Nacional de Tecnica Aeroespacial, Ctra. de Torrejon a Ajalvir, km 4, 28850 Torrejon de Ardoz (Madrid), Spain
- Scott W. Fleming
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Elaine M. Frazer
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Ana I. Gómez de Castro
- ORCiD
- Space Astronomy Research Group-AEGORA, Fac CC Matematicas, Universidad Complutense de Madrid , Plaza de Ciencias 3, 28040 Madrid, Spain
- Gregory J. Herczeg
- ORCiD
- Kavli Institute for Astronomy and Astrophysics, Peking University , Beijing 100871, People’s Republic of China; Department of Astronomy, Peking University , Beijing 100871, People’s Republic of China
- Svea Hernandez
- ORCiD
- AURA for ESA , Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
- Alec S. Hirschauer
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA; Department of Physics & Engineering Physics, Morgan State University , 1700 East Cold Spring Lane, Baltimore, MD 21251, USA
- Bethan L. James
- ORCiD
- AURA for ESA , Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
- Christopher M. Johns-Krull
- ORCiD
- Department of Physics and Astronomy, Rice University , 6100 Main Street Houston, TX 77005, USA
- Claus Leitherer
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Sean Lockwood
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Joan Najita
- ORCiD
- NSF’s NOIRLab950 N. Cherry Avenue Tucson , AZ 85719, USA
- M. S. Oey
- ORCiD
- University of Michigan , 1085 S. University Avenue, Ann Arbor, MI 48109, USA
- Cristina Oliveira
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Tyler Pauly
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- I. Neill Reid
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Adric Riedel
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- David R. Rodriguez
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- David Sahnow
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Ravi Sankrit
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Kenneth R. Sembach
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Richard Shaw
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Linda J. Smith
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- S. Tony Sohn
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Debopam Som
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Leonardo Úbeda
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- Daniel E. Welty
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- DOI
- https://doi.org/10.3847/1538-4357/adc45b
- Journal volume & issue
-
Vol. 985,
no. 1
p. 109
Abstract
Specifically selected to leverage the unique ultraviolet capabilities of the Hubble Space Telescope, the Hubble Ultraviolet Legacy Library of Young Stars as Essential Standards (ULLYSES) is a Director’s Discretionary program of approximately 1000 orbits—the largest ever executed—that produced a UV spectroscopic library of O and B stars in nearby low-metallicity galaxies and accreting low-mass stars in the Milky Way. Observations from ULLYSES combined with archival spectra uniformly sample the fundamental astrophysical parameter space for each mass regime, including spectral type, luminosity class, and metallicity for massive stars, and the mass, age, and disk accretion rate for low-mass stars. The ULLYSES spectral library of massive stars will be critical to characterize how massive stars evolve at different metallicities; to advance our understanding of the production of ionizing photons, and thus of galaxy evolution and the re-ionization of the Universe; and to provide the templates necessary for the synthesis of integrated stellar populations. The massive-star spectra are also transforming our understanding of the interstellar and circumgalactic media of low-metallicity galaxies. On the low-mass end, UV spectra of T Tauri stars contain a plethora of diagnostics of accretion, winds, and the warm disk surface. These diagnostics are crucial for evaluating disk evolution and provide important input to assess atmospheric escape of planets and to interpret powerful probes of disk chemistry, as observed with the Atacama Large Millimeter Array and the James Webb Space Telescope. In this paper, we motivate the design of the program, describe the observing strategy and target selection, and present initial results.
Keywords
