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This article is contribution 125 of Tara Oceans.-- 13 pages, 5 figures, supplementary materials https://doi.org/10.1126/sciadv.abj9309.-- Data and materials availability: The raw sediment sequencing data have been deposited to the ENA under project accessions PRJEB48517 (deep_sea) and PRJEB33873 (eDNAbyss). Accession numbers of additional raw sequencing data of pelagic and sediment samples analyzed in this study can be found in respective publications listed in table S2. All the metadata and R code to process the raw sequencing data and to reproduce the results and figures are available through a GitHub repository: https://github.com/trtcrd/DOS_V9 ; Remote deep-ocean sediment (DOS) ecosystems are among the least explored biomes on Earth. Genomic assessments of their biodiversity have failed to separate indigenous benthic organisms from sinking plankton. Here, we compare global-scale eukaryotic DNA metabarcoding datasets (18S-V9) from abyssal and lower bathyal surficial sediments and euphotic and aphotic ocean pelagic layers to distinguish plankton from benthic diversity in sediment material. Based on 1685 samples collected throughout the world ocean, we show that DOS diversity is at least threefold that in pelagic realms, with nearly two-thirds represented by abundant yet unknown eukaryotes. These benthic communities are spatially structured by ocean basins and particulate organic carbon (POC) flux from the upper ocean. Plankton DNA reaching the DOS originates from abundant species, with maximal deposition at high latitudes. Its seafloor DNA signature predicts variations in POC export from the surface and reveals previously overlooked taxa that may drive the biological carbon pump ; We further thank the following sponsors for support: the Swiss National Science Foundation (grants 31003A_159709, 31003A_1791259, and P2GEP3_171829), the Swiss Network for International Studies award (20170024), the European Research Council (grant 818449 AGENSI), CNRS (in particular, FR022), Sorbonne University, the French Government "Investissement d'Avenir" program OCEANOMICS (ANR-11-BTBR-0008), France Génomique, the Genoscope-CEA (ANR-10-INBS-09) for the project eDNAbyss (AP2016-228), Ifremer for the project Merlin "Pourquoi pas les Abysses," the German Research Foundation (grants BR1121/20-1 and BR1121/41-1 and the Center/Cluster of Excellence "The Ocean Floor—Earth's Uncharted Interface"), the German Ministry for Science and Education (grants 03G0223A and 03G0227A), EU JPIO-Oceans project MinigImpact-2 (German BMBF contract 03F0812E), Spanish Ministry of Economy and Competitiveness (CTM2016-75083-R), European Union's Horizon 2020 Research and Innovation Program (grant 678760 ATLAS), and the Gordon and Betty Moore Foundation (grant GBMF5257 UniEuk). Samples from the UK-1 and OMS license areas in the Clarion-Clipperton Zone were collected as part of the ABYSSLINE project, funded by UK Seabed Resources Development Ltd. (contract SRDL SRD100100) ; With the institutional support of the 'Severo Ochoa Centre of Excellence' accreditation (CEX2019-000928-S) ; Peer reviewed

Context. We initiated a deep-imaging survey of Scorpius-Centaurus A-F stars in 2015. These stars are predicted to host warm inner and cold outer belts of debris reminiscent of the architecture of emblematic systems such as HR 8799. Aims. We present resolved images of a ring of debris around the F5-type star HD 141011 that was observed as part of our survey. We aim to set constraints on the properties of the disk, compare them to those of other resolved debris disks in Sco-Cen, and detect companions. Methods. We obtained high-contrast coronagraphic observations of HD 141011 in 2015, 2016, and 2019 with VLT/SPHERE. We removed the stellar halo using angular differential imaging. We searched for scattered light emission from a disk in the residuals and applied a forward-modeling approach to retrieve its morphological and photometric properties. We combined our radial velocity and imaging data to derive detection probabilities for companions co-planar with the disk orientation. Results. We resolve a narrow ring of debris that extends up to ∼1.100 (∼141 au) from the star in the IRDIS and IFS data obtained in 2016 and 2019. The disk is not detected in the 2015 data which are of poorer quality. The disks is best reproduced by models of a noneccentric ring centered on the star with an inclination of 69.1 ± 0.9 ◦ , a position angle of −24.6 ± 1.7 ◦ , and a semimajor axis of 127.5 ± 3.8 au. The combination of radial velocity and imaging data excludes brown-dwarf (M > 13.6 MJup) companions coplanar with the disk from 0.1 to 0.9 au and from 20 au up to 500 au (90% probability). Conclusions. HD 141011 adds to the growing list of debris disks that are resolved in Sco-Cen. It is one of the faintest disks that are resolved from the ground and has a radial extent and fractional width (∼12.5%) reminiscent of Fomalhaut. Its moderate inclination and large semimajor axis make it a good target for the James Webb Space Telescope and should allow a deeper search for putative companions shaping the dust distribution. ; French National Research Agency (ANR) ANR-14-CE33-0018 ANR-20-CE31-0012 France from the CNRS-D2P PICS grant France from the Programmes Nationaux de Planetologie et de Physique Stellaire (PNP) France from the Programmes Nationaux de Planetologie et de Physique Stellaire (PNPS) European Research Council (ERC) 885 593 Istituto Nazionale Astrofisica (INAF) Agenzia Spaziale Italiana (ASI) 2018-16-HH.0 PRIN-INAF 2019 "Planetary systems at young ages (PLATEA)" Australian Research Council FT170100040 DP180104235 ANID, -Millennium Science Initiative Program NCN19_171 Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT) CONICYT FONDECYT 1180395 French National Research Agency (ANR) ANR10 LABX56 Spanish Government AyA2017-84089 European Commission 776403 Universidad de Valparaiso ; Versión publicada - versión final del editor

Context. A large portion of stars is found to be part of binary or higher-order multiple systems. The ubiquity of planets found around single stars raises the question of whether and how planets in binary systems form. Protoplanetary disks are the birthplaces of planets, and characterizing them is crucial in order to understand the planet formation process. Aims. Our goal is to characterize the morphology of the GG Tau A disk, one of the largest and most massive circumbinary disks. We also aim to trace evidence for binary-disk interactions. Methods. We obtained observations in polarized scattered light of GG Tau A using the SPHERE/IRDIS instrument in the H-band filter. We analyzed the observed disk morphology and substructures. We ran 2D hydrodynamical models to simulate the evolution of the circumbinary ring over the lifetime of the disk. Results. The disk and also the cavity and the inner region are highly structured, with several shadowed regions, spiral structures, and streamer-like filaments. Some of these are detected here for the first time. The streamer-like filaments appear to connect the outer ring with the northern arc. Their azimuthal spacing suggests that they may be generated through periodic perturbations by the binary, which tear off material from the inner edge of the outer disk once during each orbit. By comparing observations to hydrodynamical simulations, we find that the main features, in particular, the gap size, but also the spiral and streamer filaments, can be qualitatively explained by the gravitational interactions of a binary with a semimajor axis of similar to 35 au on an orbit coplanar with the circumbinary ring. ; European Research Council under the Horizon 2020 Framework Program via the ERC Advanced Grant Origins 83 24 28 French National Research Agency (ANR) ANR-16-CE31-0013 Australian Research Council FT170100040 DP180104235 European Union's Horizon 2020 research and innovation programme under the Marie Skodowska-Curie grant 823823 Comisión Nacional de Investigación Científica y Tecnológica (CONICYT) CONICYT FONDECYT 11190837 ESO Centre National de la Recherche Scientifique (CNRS) MPIA (Germany) Istituto Nazionale Astrofisica (INAF) FINES (Switzerland) NOVA (The Netherlands) European Union (EU) RII3-Ct2004-001566 European Union (EU) 226604 312430