Kyle Kremer et al 2019 ApJ 885 2
N-body models show that 10%–50% of primordial planetary systems in dense star clusters can be broken through dynamical encounters over a cluster’s full lifetime, populating clusters with “free-floating” planets.
Hadis Goodarzi et al 2019 ApJS 244 37
Analysis of the light curves of 1740 flare stars indicates that flare frequency and the total power of flares correlates with increasing relative magnetic feature coverage and contrast in F–M-type stars.
Daniel R. Weisz et al 2019 ApJL 885 L8
Investigation of 20 faint M31 satellites indicates they all quenched 3–9 billion years ago, in contrast to Milky Way satellites that are either faint with ancient quenching times, or luminous with recent quenching times.
P. M. Shober et al 2019 AJ 158 183
An extremely slow fireball was recently observed travelling at just 11 km/s. This object was a “minimoon”, or a temporarily captured orbiter — an object gravitationally captured by the Earth-Moon system.
Carl J. Grillmair 2019 ApJ 884 174
From photometry and proper motions from the Gaia Data Release 2, a 50° long stream of about 70 stars have been detected extending westward from the halo globular cluster M5.
M. R. Combi et al 2019 ApJL 884 L39
SOHO observations of the hydrogen coma of comet C/2017 S3 (PanSTARRS) allow for an estimate of the size of the nucleus of the comet just before its final outburst and apparent disintegration.