We now have 156 confirmed extrasolar planets orbiting 133 stars, making for 17 multiple planet systems. Keeping up with these fast-breaking discoveries is a challenge, but Julia Espresate at the Instituto de Astronomía (Ciudad Universitaria, Mexico) has produced two useful catalogs now available on the arXiv site. The first lists stellar data including spectral type, luminosity, rotation period, stellar metalicity, age and other factors for the 133 stars. The second provides a breakdown of data for the 156 extrasolar planets so far detected.

Good information on extrasolar planets has been available on the Internet for a while, as witness the Extrasolar Planets Encyclopaedia. What has been lacking is a source that ties together the planetary information with data on the characteristics of the parent stars — the latter tend to be widely scattered in the scientific literature. Thus the utility of Espresate’s work, which also reveals how great are our gaps in knowledge of these systems. Almost 40 percent of the stars examined have no reported rotation period, for example, while 10 percent have no reported luminosity class.

We are, in short, finding planets much faster than we can study them in detail. Espresate’s paper “Catalog of 156 Confirmed Extrasolar Planets and Their 133 Parent Stars” is to be published in Revista Mexicana de Astronomía y Astrofisíca.