For more than 30 years, the Hubble Space Telescope has been making groundbreaking discoveries that help us better understand the universe. Recently, a team of scientists and engineers conducted one of the largest and most ambitious Hubble missions ever executed. They collected data on nearly 500 stars over his three years, resulting in new insights into star formation, evolution, and impact on their surroundings.
In December 2023, astronomers completed the ULLYSES (Ultraviolet Legacy Library of Young Stars as an Essential Standard) survey. Provides a comprehensive spectroscopic data set for ultraviolet light. Because ultraviolet light can only be observed from space, Hubble is the only active telescope capable of conducting this research. The resulting dataset is expected to be valuable for decades to come.
The ULLYSES team conducted research on 220 stars and combined their observations with data from the Hubble archive on an additional 275 stars. The program also included information from the world’s largest and most powerful ground-based telescopes and the X-ray Space Telescope. The ULLYSES dataset contains star spectra that provide information about each star’s temperature, chemical composition, and rotation.
what are we seeing?
ULLYSES is a program that analyzes two types of stars: extremely hot giant blue stars and young stars with less mass than the Sun. Blue stars are incredibly bright and emit ultraviolet radiation that Hubble can detect. Its strong winds shape the evolution of galaxies and supply them with the elements necessary for life. These elements are produced through nuclear fusion and released into space as stars die. ULLYSES focuses on blue stars found in nearby galaxies that lack elements heavier than helium and hydrogen, which were prevalent in the early universe.
Young stars with less mass than the Sun emit high-energy radiation, such as ultraviolet light and X-rays, while they are still growing. They gain mass by collecting material from the surrounding disk of dust and gas that forms the planet. Hubble’s spectra provide important information about the process by which young stars gain mass and the amount of energy released into the surrounding planet-forming disk and nearby environment. Ultraviolet radiation emitted by young stars affects the formation of planets and their habitability. Stars in this category are located in nearby star-forming regions within the Milky Way.
Julia Roman-Duval, ULLYSES Implementation Team Leader, Space Telescope Science Institute (STScI), Baltimore, Maryland; commented.
“We believe the ULLYSES project is revolutionary and will have an impact across astrophysics, from exoplanets to the influence of massive stars on the evolution of galaxies, to understanding the early stages of the evolving universe. Apart from the program’s specific goals, stellar data can also be used in the field of astrophysics in ways we cannot yet imagine.”
[via Space.com]
