Two roads through the green valley

Two roads through the green valley

Large surveys of galaxies have revealed a bimodal color distribution: most galaxies tend to be red or blue, leaving a gap in the middle known as the green valley. The authors of this paper use morphologies provided by the Galaxy Zoo project to show that not all galaxies take the same quick path through the green valley.

The Evolution of the Bar Fraction

The Evolution of the Bar Fraction

Astronomers have long wished to probe the number of galaxies containing bar structures to ever increasing redshifts. This paper discusses the first results from the Galaxy Zoo Hubble classifications of galaxies out to redshifts of z = 1, in order to study how the fraction of galaxies containing a bar has changed over a cosmic time that has previously not been explored.

Galaxy Zoo 2: Return of the Citizen Scientist

Galaxy Zoo 2: Return of the Citizen Scientist

Galaxy Zoo is a citizen science project that uses volunteers to classify galaxies from the Sloan Digitial Sky Survey as spiral or elliptical. Now the Galaxy Zoo 2 catalogue has gone public, with even more detailed classifications of galaxies, including bars, bulges, spiral arms, and round and squashed ellipticals.