Qicheng Zhang et al 2019 AJ 157 201

Threatening comets may be deflected via artificial heating (e.g., by a laser) that causes sublimation jets to change the comet’s course. Strategies must also be employed to avoid comet fragmentation during deflection.

Nobuyuki Sakai et al 2019 ApJ 876 30

Methanol masers in the outer regions of the Perseus arm reveal motions consistent with models for spiral arm formation that involve gas entering an arm to be shocked and then to form stars.

Prabal Saxena et al 2019 ApJL 876 L16

The observed degree of depletion of sodium and potassium in lunar samples and the evolution of activity of solar analogs over time suggest that the primordial Sun is highly likely to have been a slow rotator.

Ashley Chontos et al 2019 AJ 157 192

KOI 4.01, Kepler’s first discovered planet candidate, has finally been confirmed via a combination of asteroseismology and radial velocities; it is the closest known planet in terms of orbital period to an evolved star.

Alexandre Emsenhuber and Erik Asphaug 2019 ApJ 875 95

In similar-sized planetary collisions, a significant part of the impactor often continues downrange. Roughly 50% of these “runners” reimpact their target planets; the others remain in orbit for tens of millions of years.

Dong-Woo Kim et al 2019 ApJS 241 36

In a new project, spatially resolved 2D spectral maps have been created of the hot gas from 70 individual early-type galaxies; they are available for general use at the Chandra Galaxy Atlas (CGA) website.