Substellar mass function of the field

Preliminary Trigonometric Parallaxes of 184 Late-T and Y Dwarfs and an Analysis of the Field Substellar Mass Function into the "Planetary" Mass Regime

We present preliminary trigonometric parallaxes of 184 late-T and Y dwarfs using observations from Spitzer (143), USNO (18), NTT (14), and UKIRT (9). To complete the 20-pc census of $\ge$T6 dwarfs, we combine these measurements with previously published trigonometric parallaxes for an additional 44 objects and spectrophotometric distance estimates for another 7.

https://arxiv.org/abs/1812.01208

A method to analyse velocity structure

We present a new method of analysing and quantifying velocity structure in star forming regions suitable for the rapidly increasing quantity and quality of stellar position-velocity data. The method can be applied to data in any number of dimensions, does not require the centre or characteristic size (e.g.

https://arxiv.org/abs/1812.05628

Consistent modelling of proto-planetary disks

Consistent dust and gas models for protoplanetary disks III. Models for selected objects from the FP7 DIANA project

The European FP7 project DIANA has performed a coherent analysis of a large set of observations from protoplanetary disks by means of thermo-chemical disk models. The collected data include extinction-corrected stellar UV and X-ray input spectra (as seen by the disk), photometric fluxes, low and high resolution spectra, interferometric data, emission line fluxes, line velocity profiles and line maps.

http://arxiv.org/abs/1812.02741

A super-Earth orbiting Barnard's star

A super-Earth orbiting Barnard's star
https://phys.org/news/2018-11-astronomers-super-earth-barnard-star.html

First light for SPECULOOS

https://phys.org/news/2018-12-speculoos.html