Junjie Mao et al 2021 ApJL 918 L17
Measurements derived from X-ray observations by XMM-Newton suggest that a simple chemical enrichment model can’t explain the chemical abundance patterns in a pair of colliding galaxies.
Nikku Madhusudhan et al 2021 ApJ 918 1
Ocean worlds with hydrogen-rich atmospheres might have readily detectable biosignatures and may be habitable over a wider range of planetary masses and orbital distances than traditional terrestrial planets.
José G. Fernández-Trincado et al 2021 ApJL 918 L9
A tentative correlation between the abundances of cerium, nitrogen, and aluminum in globular cluster stars might arise via several different pathways, such as rotational mixing in fast-rotating “spinstars.”
Stuart J. Robbins and Kelsi N. Singer 2021 Planet. Sci. J. 2 192
The presence of an unexpected feature in the crater size distribution of Pluto and its largest moon, Charon, is confirmed, prompting questions about the formation history of icy bodies in the outer solar system.
Izumi Endo et al 2021 ApJ 917 103
Laboratory experiments involving carbon- and nitrogen-rich compounds suggest that organic species could be responsible for some of the unidentified infrared spectral features of dusty classical novae.
Annaliese Miller et al 2021 AJ 162 131
Modeling suggests that a curious binary system is made up of two stars that have exchanged so much mass over their five-billion-year lifetime that their mass ratio has completely flipped.