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We present Multi-Unit Spectroscopic Explorer (MUSE) integral-field spectroscopy of ESO 253-G003, which hosts a known active galactic nucleus (AGN) and the periodic nuclear transient ASASSN-14ko, observed as part of the All-weather MUse Supernova Integral-field of Nearby Galaxies survey. The MUSE observations reveal that the inner region hosts two AGN separated by 1.4±0.1 kpc (≍1 ′′. 7). The brighter nucleus has asymmetric broad permitted emission-line profiles and is associated with the archival AGN designation. The fainter nucleus does not have a broad emission-line component but exhibits other AGN characteristics, including vFWHM≈700 km~s−1 forbidden line emission, log10([OIII]/Hβ)≈1.1 , and high-excitation potential emission lines, such as [Fe VII] λ6086 and He II λ4686. The host galaxy exhibits a disturbed morphology with large kpc-scale tidal features, potential outflows from both nuclei, and a likely superbubble. A circular relativistic disc model cannot reproduce the asymmetric broad emission-line profiles in the brighter nucleus, but two non-axisymmetric disc models provide good fits to the broad emission-line profiles: an elliptical disc model and a circular disc + spiral arm model. Implications for the periodic nuclear transient ASASSN-14ko are discussed. ; MAT acknowledges support from the DOE CSGF through grant no. DE-SC0019323. BJS and CSK are supported by NSF grant no. AST-1907570. BJS is also supported by NASA grant no. 80NSSC19K1717 and NSF grants AST-1920392 and AST-1911074. CSK is supported by NSF grant no. AST-181440. KAA is supported by the Danish National Research Foundation (DNRF132). Support for JLP is provided in part by FONDECYT through grant n.1191038 and by the Ministry for the Economy, Development, and Tourism's Millennium Science Initiative through grant no. IC120009, awarded to The Millennium Institute of Astrophysics, MAS. LG acknowledges financial support from the Spanish Ministry of Science, Innovation and Universities (MICIU) under the 2019 Ramón y Cajal program RYC2019-027683 and from the Spanish MICIU project PID2020-115253GA-I00. Parts of this research were supported by the Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE170100013. LG was funded by the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 839090, and partially supported by the Spanish grant no. PGC2018-095317-B-C21 within the European Funds for Regional Development (FEDER). Support for TW-SH was provided by NASA through the NASA Hubble Fellowship grant no. #HST-HF2-51458.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555. Based on observations collected at the European Organization for Astronomical Research in the Southern Hemisphere under ESO programme 096.D-0296(A). ; Peer reviewed

Honorary degrees and particularly doctorates are important instruments to enhance the standing of universities and professors, in addition to receiving these as a measure of a scientist's recognition. Jacobus C. Kapteyn from the University of Groningen in the Netherlands, one of the most prominent astronomers of his times, received three of these and has persuaded his university to award at least three, possibly five. I examine the background of the selection of the latter in view of developments in Kapteyn's time in his career, international astronomy and political and cultural circumstances.

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society © 2012 RAS © 2012 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. ; In this work we present a detailed analysis of the global and fine structure of four middlemass disc galaxies obtained from hydrodynamic simulations in a cold dark matter ( CDM) scenario. These objects have photometric disc-to-total ratios in good agreement with those observed for late-type spirals, as well as kinematic properties in agreement with the observational I-band Tully–Fisher relation.We identify the different dynamical components at redshift zero on the basis of both orbital parameters and the binding energy of stars in the galaxy. In this way, we recognize a slowly rotating centrally concentrated spheroid, and two disc components supported by rotation: a thin discwith stars in nearly circular orbits, and a thick disc with orbital parameters transitional between the thin disc and the spheroid. The spheroidal component is composed mainly by old, metal-poor and α-enhanced stars. The distribution of metals in this component shows, however, a clear bimodality with a low-metallicity peak, which could be related to a classical bulge formed from rapid collapse at early times, and a high-metallicity peak, which could be related to a pseudo-bulge formed from instabilities of the inner disc. The thin disc appears in our simulations as the youngest and most metal-rich component, with median stellar ages ranging from 3.8 to 6.7 Gyr. The radial distribution of ages and colours in this component is U-shaped: the new stars are forming in the inner regions, where the galaxy is bluer, and then migrate through secular processes reaching the outer parts. Finally, we also find in all simulated galaxies a thick disc containing about 16 per cent of the total stellar mass and with properties that are intermediate between those of the thin disc and the spheroid. Its low-metallicity stars are α-enhanced when compared to thin disc stars of the same metallicity. The structural parameters (e.g. the scale height) of the simulated thick discs suggest that such a component could result from the combination of different thickening mechanisms that include merger-driven processes, but also long-lived internal perturbations of the thin disc. ; This work was partially supported by the DGES (Spain) through the grants AYA2009-12792-C03-02 and AYA2009-12792- C03-03 from the PNAyA, MICINN, Spain. We also thank the ASTROMADRID network (CAM S2009/ESP-1496) from the Madrid regional government, and the 'Supercomputación y e-Ciencia' Consolider-Ingenio 2010 project (CSD2007-0050), MICINN, Spain.