Gas in the halos of galaxies dominates the universe's baryon budget, traces its dark-matter potential wells, and supplies the fuel for star formation. Circumgalactic gas has also long been suspected to regulate galaxy...

The circumgalactic medium (CGM) can be viewed as an atmosphere that surrounds a galaxy and sustains star formation within it. Much of what we know about the CGM has come from absorption-line spectroscopy, mainly in the...

Whether you're already working with Galaxy Zoo data, curious about how it might inform your science, or if you just want to spend a few days thinking about galaxy evolution, we hope you'll join us. With more large...

This year we celebrate the 50th anniversary of this discovery, and honor Maarten Schmidt, whose insight into the nature of quasar spectra was a decisive milestone in the rise of this new field of research, in addition to...