Galaxy Zoo: an unusual new class of galaxy cluster
  We have identified a new class of galaxy cluster using data from the Galaxy
Zoo project. These clusters are rare, and thus have apparently gone unnoticed
before, despite their unusual properties. They appear especially anomalous when
the morphological properties of their component galaxies are considered. Their
identification therefore depends upon the visual inspection of large numbers of
galaxies, a feat which has only recently been made possible by Galaxy Zoo,
together with the Sloan Digital Sky Survey. We present the basic properties of
our cluster sample, and discuss possible formation scenarios and implications
for cosmology.
