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The Space Telescope Science Institute (STScI) Director has decided to devote up to 1000 orbits of Director.s Discretionary time in observing Cycles 27-29 to a new Hubble Ultraviolet Legacy program focused on star formation and associated stellar physics. This new program comma ULLYSES (UV Legacy Library of Young Stars as Essential Standards) comma will provide a UV spectroscopic reference sample of young (< 10 Myr) high- and low-mass stars. It will target over virgul150 OB stars in the Magellanic Clouds and lower metallicity galaxies in the Local Group comma and virgul40 T Tauri stars and brown dwarfs in the Milky Way. In addition comma ULLYSES will monitor 4 typical T Tauri stars over different rotational phases through at least three rotation periods comma and over timescales of months to years. The resulting library will provide template spectra of massive stars at metallicities substantially below the well studied comma while the low mass sample will cover a wide range of ages comma accretion rates comma and masses comma including objects down to well below 0.5 M_sun. The legacy of this large UV dataset on the first 10 Myr of stellar evolution will be enhanced by complementary datasets obtained by the scientific community. In addition to the core goals of the program related to stellar astrophysics of low and high mass stars comma this data will also enable exciting science in the fields of ISM comma CGM comma jets comma and exoplanets. ULLYSES will be modeled after the Frontier Fields programdoublePoint all data obtained will be non-proprietary. The implementation team at STScI is developing high-level science data products and a sophisticated database and website for disseminating data from the ULLYSES program and ancillary datasets for the ULLYSES target sample from space and ground-based facilities.

空间望远镜科学研究所（Space Telescope Science Institute，STScI）所长已决定，在第27至29号观测周期中，将最多1000个主任酌情分配观测轨道，用于一项全新的哈勃紫外遗产项目，该项目聚焦恒星形成及相关恒星物理研究。这项名为ULLYSES（青年恒星核心标准紫外遗产库，UV Legacy Library of Young Stars as Essential Standards）的新项目，将构建年龄小于10百万年（Myr）的高、低质量恒星的紫外光谱参考样本。观测目标涵盖麦哲伦星云中的约150颗O型与B型星（OB星）、本星系群内金属丰度更低的星系，以及银河系内的约40颗金牛T星（T Tauri stars）与褐矮星（brown dwarfs）。此外，ULLYSES将对4颗典型金牛T星开展监测：覆盖至少3个完整自转周期的不同自转相位，监测时长跨度为数月至数年。最终得到的光谱库将提供金属丰度远低于已被充分研究的大质量恒星的模板光谱；而低质量恒星样本则将覆盖广泛的年龄、吸积率与质量范围，包括质量远低于0.5倍太阳质量（M_sun）的天体。本数据集针对恒星演化最初10百万年的研究遗产价值，还将通过科学界获取的互补数据集进一步提升。除了围绕低质量与大质量恒星的恒星天体物理学核心目标外，该数据集还将助力星际介质（ISM）、星系周介质（CGM）、喷流（jets）与系外行星（exoplanets）等领域的前沿科学研究。ULLYSES将参照哈勃前沿视野项目（Frontier Fields program）的模式开展，所有获取的数据均将无专属权开放。STScI的实施团队正在开发高级科学数据产品、一套完善的数据库与专属网站，用于发布ULLYSES项目的数据以及该项目目标样本的空间与地面观测辅助数据集。

搜集汇总

背景与挑战

背景概述

该数据集是欧洲空间局提供的哈勃太空望远镜科学观测提案，专注于大麦哲伦云中O7型超巨星的紫外和可见光光谱研究，使用COS和STIS仪器于2022年底进行观测。它旨在支持低金属丰度环境下恒星风结构和电离外流的量化分析，相关成果已发表在科学文献中。数据集包含校准后的光谱数据，适用于恒星演化、星际介质等天文领域的研究。