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Overview of the Solar Radiation and Climate Experiment (SORCE) Seventeen-Year Mission
Woods, Thomas N.; Kopp, Greg; Harder, Jerald W. +4 more
The Solar Radiation and Climate Experiment (SORCE) was a NASA mission that operated from 2003 to 2020 to provide key climate-monitoring measurements of total solar irradiance (TSI) and solar spectral irradiance (SSI). Three important accomplishments of the SORCE mission are i) the continuation of the 42-year-long TSI climate data record, ii) the c…
A Blueprint for the Milky Way's Stellar Populations. II. Improved Isochrone Calibration in the SDSS and Pan-STARRS Photometric Systems
Beers, Timothy C.; An, Deokkeun
We improve the identification and isolation of individual stellar populations in the Galactic halo based on an updated set of empirically calibrated stellar isochrones in the Sloan Digital Sky Survey and Pan-STARRS 1 photometric systems. Along the Galactic prime meridian (l = 0° and 180°), where proper motions and parallaxes from Gaia DR2 can be u…
The Cosmic Ultraviolet Baryon Survey (CUBS). II. Discovery of an H2-bearing DLA in the Vicinity of an Early-type Galaxy at z = 0.576
Faucher-Giguère, Claude-André; Johnson, Sean D.; Petitjean, Patrick +18 more
We report the serendipitous detection of an H2-bearing damped Lyα absorber at z = 0.576 in the spectrum of the QSO J0111-0316 in the Cosmic Ultraviolet Baryon Survey. Spectroscopic observations from Hubble Space Telescope-COS in the far-ultraviolet reveal a damped absorber with log[N(H I)/cm-2] = 20.1 ± 0.2 and log[N(H2<…
The Young Massive Star Cluster Westerlund 2 Observed with MUSE. III. A Cluster in Motion—The Complex Internal Dynamics
Sabbi, Elena; Nota, Antonella; Zeidler, Peter +1 more
Analyzing the dynamical state of nearby young massive star clusters is essential for understanding star cluster formation and evolution during their earliest stages. In this work we analyze the stellar and gas kinematics of the young massive star cluster Westerlund 2 (Wd2) using data from the integral field unit Multi Unit Spectroscopic Explorer (…
First observations and performance of the RPW instrument on board the Solar Orbiter mission
Müller, D.; Hellinger, P.; André, M. +107 more
The Radio and Plasma Waves (RPW) instrument on the ESA Solar Orbiter mission is designed to measure in situ magnetic and electric fields and waves from the continuum up to several hundred kHz. The RPW also observes solar and heliospheric radio emissions up to 16 MHz. It was switched on and its antennae were successfully deployed two days after the…
The Far-away Blues: Exploring the Furthest Extents of the Boötes I Ultra-faint Dwarf Galaxy
Wyse, Rosemary F. G.; Filion, Carrie
Establishing the spatial extents and the nature of the outer stellar populations of dwarf galaxies is necessary for the determination of their total masses, current dynamical states, and past evolution. We here describe our investigation of the outer stellar content of the Boötes I ultra-faint dwarf galaxy, a satellite of the the Milky Way. We ide…
The Spatial and Temporal Variations of Turbulence in a Solar Flare
Kontar, Eduard P.; Jeffrey, Natasha L. S.; Stores, Morgan
Magnetohydrodynamic plasma turbulence is believed to play a vital role in the production of energetic electrons during solar flares, and the nonthermal broadening of spectral lines is a key sign of this turbulence. Here, we determine how flare turbulence evolves in time and space using spectral profiles of Fe XXIV, Fe XXIII, and Fe XVI, observed b…
ν Gem: A Hierarchical Triple System with an Outer Be Star
Gies, Douglas R.; Klement, Robert; Rivinius, Thomas +17 more
Time series of spectroscopic, speckle-interferometric, and optical long-baseline-interferometric observations confirm that ν Gem is a hierarchical triple system. It consists of an inner binary composed of two B-type stars and an outer classical Be star. Several photospheric spectral lines of the inner components were disentangled, revealing two st…
An enquiry on the origins of N-rich stars in the inner Galaxy based on APOGEE chemical compositions
Bizyaev, Dmitry; Brownstein, Joel R.; Pan, Kaike +10 more
Recent evidence based on APOGEE data for stars within a few kpc of the Galactic Centre suggests that dissolved globular clusters (GCs) contribute significantly to the stellar mass budget of the inner halo. In this paper, we enquire into the origins of tracers of GC dissolution, N-rich stars, that are located in the inner 4 kpc of the Milky Way. Fr…
A search for trends in spatially resolved debris discs at far-infrared wavelengths
Marshall, J. P.; Wang, L.; Kennedy, G. M. +2 more
Debris discs around main-sequence stars are belts of planetesimals - asteroids and comets - formed in the protoplanetary discs around young stars. Planetesimals comprise both the building blocks of planets around young stars and the source of dusty debris around older stars. Imaging observations of dust continuum emission and scattered light revea…