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A new radio catalogue for M83: supernova remnants and H II regions
DOI: 10.1093/mnras/staa1177 Bibcode: 2020MNRAS.495..479R

Soria, Roberto; White, Richard L.; Blair, William P. +3 more

We present a new catalogue of radio sources in the face-on spiral galaxy M83. Radio observations taken in 2011, 2015, and 2017 with the Australia Telescope Compact Array at 5.5 and 9 GHz have detected 270 radio sources. Although a small number of these sources are background extragalactic sources, most are either H II regions or supernova remnants…

2020 Monthly Notices of the Royal Astronomical Society
eHST 14
A giant galaxy in the young Universe with a massive ring
DOI: 10.1038/s41550-020-1102-7 Bibcode: 2020NatAs...4..957Y

Kacprzak, Glenn G.; Glazebrook, Karl; Labbé, Ivo +12 more

In the local (redshift z ≈ 0) Universe, collisional ring galaxies make up only ~0.01% of galaxies1 and are formed by head-on galactic collisions that trigger radially propagating density waves2-4. These striking systems provide key snapshots for dissecting galactic disks and are studied extensively in the local Universe5…

2020 Nature Astronomy
eHST 14
A novel approach for optimal trajectory design with multiple operation modes of propulsion system, part 2
DOI: 10.1016/j.actaastro.2020.02.047 Bibcode: 2020AcAau.172..166T

Taheri, Ehsan; Junkins, John L.; Kolmanovsky, Ilya +1 more

Equipping a spacecraft with multiple solar-powered electric engines (of the same or different types) compounds the task of optimal trajectory design due to presence of both real-valued inputs (power input to each engine in addition to the direction of thrust vector) and discrete variables (number of active engines). Each engine can be switched on/…

2020 Acta Astronautica
Rosetta 14
On the Production of He+ of Solar Origin in the Solar Wind
DOI: 10.3847/1538-4357/aba4a9 Bibcode: 2020ApJ...899...11R

Landi, Enrico; Rivera, Yeimy J.; Lepri, Susan T. +1 more

Solar wind measurements in the heliosphere predominantly comprise protons, alphas, and minor elements in a highly ionized state. The majority of low-charge states, such as He+, measured in situ are often attributed to pick-up ions of nonsolar origin. However, through inspection of the velocity distribution functions of near-Earth measur…

2020 The Astrophysical Journal
Ulysses 14
Quantifying the structure of strong gravitational lens potentials with uncertainty-aware deep neural networks
DOI: 10.1093/mnras/staa3201 Bibcode: 2020MNRAS.499.5641V

Vernardos, Georgios; Tsagkatakis, Grigorios; Pantazis, Yannis

Gravitational lensing is a powerful tool for constraining substructure in the mass distribution of galaxies, be it from the presence of dark matter sub-haloes or due to physical mechanisms affecting the baryons throughout galaxy evolution. Such substructure is hard to model and is either ignored by traditional, smooth modelling, approaches, or tre…

2020 Monthly Notices of the Royal Astronomical Society
eHST 14
Titan's neutral atmosphere seasonal variations up to the end of the Cassini mission
DOI: 10.1016/j.icarus.2019.113413 Bibcode: 2020Icar..34413413C

Flasar, F. M.; Lavvas, P.; Coustenis, A. +4 more

In this paper we report new results concerning the seasonal atmospheric evolution near Titan's poles and equator in terms of temperature and composition using nadir spectra acquired by the Cassini Composite Infrared Spectrometer (CIRS) at high spectral resolution during the last year of the Cassini mission in 2017 complementing previous investigat…

2020 Icarus
Cassini 14
Detection of Pb II in the Ultraviolet Spectra of Three Metal-poor Stars
DOI: 10.3847/2041-8213/abbc21 Bibcode: 2020ApJ...902L..24R

Beers, Timothy C.; Placco, Vinicius M.; Holmbeck, Erika M. +8 more

We report the first detection of the Pb II line at 2203.534 Šin three metal-poor stars, using ultraviolet spectra obtained with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope. We perform a standard abundance analysis assuming local thermodynamic equilibrium (LTE) to derive lead (Pb, Z = 82) abundances. The Pb II line …

2020 The Astrophysical Journal
eHST 14
The large-scale magnetic field of the eccentric pre-main-sequence binary system V1878 Ori
DOI: 10.1093/mnras/staa1993 Bibcode: 2020MNRAS.497..632L

Hussain, G. A. J.; Alecian, E.; Kochukhov, O. +4 more

We report time-resolved, high-resolution optical spectropolarimetric observations of the young double-lined spectroscopic binary V1878 Ori. Our observations were collected with the ESPaDOnS spectropolarimeter at the Canada-France-Hawaii Telescope through the BinaMIcS large programme. V1878 Ori A and B are partially convective intermediate mass wea…

2020 Monthly Notices of the Royal Astronomical Society
XMM-Newton 14
Tracking the year-to-year variation in the spectral energy distribution of the narrow-line Seyfert 1 galaxy Mrk 335
DOI: 10.1093/mnras/staa2817 Bibcode: 2020MNRAS.499.1266T

Komossa, S.; Gallo, L. C.; Grupe, D. +5 more

Multiwavelength monitoring of Mrk 335 with Swift between 2007 and 2019 are used to construct annual spectral energy distributions (SEDs) and track year-to-year changes. Non-contemporaneous archival data prior to 2007 are used to build a bright state SED. In this work, the changes are examined and quantified to build the foundation for future SED m…

2020 Monthly Notices of the Royal Astronomical Society
XMM-Newton eHST 14
Detection of green line emission in the dayside atmosphere of Mars from NOMAD-TGO observations
DOI: 10.1038/s41550-020-1123-2 Bibcode: 2020NatAs...4.1049G

Aoki, S.; Vandaele, A. C.; Daerden, F. +13 more

The oxygen emission at 557.7 nm is a ubiquitous component of the spectrum of the terrestrial polar aurora and the reason for its usual green colour1. It is also observed as a thin layer of glow surrounding the Earth near 90 km altitude in the dayside atmosphere2,3 but it has so far eluded detection in other planets. Here we r…

2020 Nature Astronomy
ExoMars-16 14