Search Publications
A measurement of the Hubble constant from angular diameter distances to two gravitational lenses
Fassnacht, Christopher D.; Hilbert, Stefan; Suyu, Sherry H. +3 more
The local expansion rate of the Universe is parametrized by the Hubble constant, H0, the ratio between recession velocity and distance. Different techniques lead to inconsistent estimates of H0. Observations of Type Ia supernovae (SNe) can be used to measure H0, but this requires an external calibrator to convert relative distances to absolute one…
Close Cassini flybys of Saturn's ring moons Pan, Daphnis, Atlas, Pandora, and Epimetheus
Brown, R. H.; Baines, K. H.; Buratti, B. J. +35 more
Saturn's main ring system is associated with a set of small moons that either are embedded within it or interact with the rings to alter their shape and composition. Five close flybys of the moons Pan, Daphnis, Atlas, Pandora, and Epimetheus were performed between December 2016 and April 2017 during the ring-grazing orbits of the Cassini mission. …
Close-range remote sensing of Saturn's rings during Cassini's ring-grazing orbits and Grand Finale
Nicholson, Philip D.; Hedman, Matthew M.; Sotin, Christophe +22 more
Saturn's rings are an accessible exemplar of an astrophysical disk, tracing the Saturn system's dynamical processes and history. We present close-range remote-sensing observations of the main rings from the Cassini spacecraft. We find detailed sculpting of the rings by embedded masses, and banded texture belts throughout the rings. Saturn-orbiting…
Galactic archaeology with Gaia
Wyse, Rosemary
The past and present merger activity of the Milky Way galaxy has recently been put into sharp focus through the analysis of data from the Gaia astrometric satellite. These data were released by the European Space Agency in 2016 (DR1) and 2018 (DR2). The emerging picture created is one of persistent disequilibrium, with high merger activity some 10…