Using N-body simulations, researchers examine the outcomes of planetesimal growth in protoplanetary disks in which planetesimals are clustered within rings rather than distributed evenly throughout the disk.

A radio megahalo surrounding a merging galaxy cluster has been observed at a frequency higher than 144 megahertz for the first time, opening up the possibility of performing spectral studies of these objects.

The discovery of an 18-solar-mass star at 34 kiloparsecs from the center of the Andromeda Galaxy, along with a wispy arm of hydrogen gas, suggest that massive stars can form in tenuous gas environments.

Simulations show that impacts can produce deposits of iron-rich material thick enough to account for lunar magnetic anomalies, but the predicted distribution of material doesn’t match observations.

If caused by a second black hole, the 11-year and 0.9-year periodic behaviors seen in Messier 87’s jet would be due to a black hole with a mass between a few million and a few billion solar masses.

Using the Atacama Large Millimeter/submillimeter Array, researchers have detected multiple sulfur-containing species; the data support a formation pathway for S₂H molecules on the surfaces of dust grains.