Metallicity maps of the Sagittarius stream show a gradient in metallicity that corresponds to a radial metallicity gradient in the Sagittarius dwarf galaxy that was torn apart in the creation of the stream.
Cygnus X-1 is an X-ray binary and one of the first systems known to contain a stellar-mass black hole; modeling yields a variety of estimates for this black hole’s spin, ranging from less than 0.1 to 0.9.
A newly discovered exoplanet in the LHS 1678 system is about the size of Earth but receives far more radiation, placing it in its star’s “Venus zone” along with one of its planetary siblings.
Two massive quiescent galaxies that are among the brightest galaxies in their home cluster are in the process of merging; the merger product may well be the brightest galaxy in the cluster.
Data from the Chandra X-ray Observatory suggest that the X-rays from the galactic center “chimney” come from a cylindrical column of plasma that may be energized by a series of accretion events.
A newly discovered planet in the HD 104067 system is likely rocky, and the tidal tugs of its planetary siblings might raise its surface temperature as high as 2600K, making it glow like a lightbulb.