Nature vs. nurture in the evolution of galaxies is not completely understood. Where a galaxy is found, its environment, can play an important role in determining the properties of that galaxy. This may not always be true, however.
Simulations show that the Oort cloud contains eight billion asteroids (in addition to hundreds of billions of comets). Do these asteroids pose a threat to Earth?
Yang et al. use climate models to investigate whether rocky exoplanets around M-stars can retain their oceans in the face of tidal locking.
Those of us who love astrobiology get really worked up about the lack of Earth-sized exoplanets found at Earth-like distances from their stars. All we want, we who hope for lots of extraterrestrial life, is a bunch of Earth-like planets doing Earth-like things so we can feel better about the odds for lots of Earth-like life in the universe.
What kind of lens is a BBH merger? These authors present the first pictures of light sources lensed by numerical models of BBH mergers.
Satellite galaxies orbiting a host galaxy seem to display highly anisotropic angular distributions.