Exploring Kepler's library

Last week's data release from Kepler appears to have temporarily overwhelmed both professional and amateur exoplanet enthusiasts. After the initial flurry of basic overview posts on the Kepler data, I noticed a conspicuous hush fall over many of my favorite astronomy blogs, presumably caused by their authors turning en masse to parse the new treasure trove.

The list of more than 1200 candidate planets will likely yield more than a thousand actual confirmed worlds once culled of false positives. One system, Kepler-11, contains six confirmed transiting planets, and another system, KOI 157, has five candidates. Eight systems have been found with four candidate planets, along with 45 triple-planet and 115 double-planet systems. It's a lot to digest, and only represents the first four months of data from a 3.5-year mission.

Fortunately, the incapacitating shock of the breadth and depth of the new dataset seems to be wearing off, and researchers are beginning to reveal some of their initial explorations. In particular, Daniel Fabrycky, a University of California-Santa Cruz astronomy post-doc and member of the Kepler team, has created an impressive visualization of projected orbital motions for all the multi-planet systems Kepler has discovered to date. Within each system, planets are color-coded according to size, with the redder planets being larger and bluer planets being smaller.

It's hard to overstate the magnitude of the insights that can potentially be extracted from novel presentations of Kepler's raw data and its present and future planetary ensemble. Though each planetary system constitutes an essentially static snapshot of only one outcome from eons-long stochastic processes, lurking in the aggregate are lessons about how exactly planets form, how orbital configurations change over time, the relative distributions of planetary size, and frequency and how a star's age, size, and mass determine the sorts of planets it produces.

Sometimes these rules and the relationships between them may clearly manifest through a simple chart or graph of two key variables, but in other cases they may only reveal themselves through more dynamic presentations and multivariate analyses that better leverage the pattern-recognition capabilities of people. In this way, Kepler's large, diverse data sets may stimulate not only a more robust understanding of stellar and planetary science, but also significant progress in the effective design and usage of scientific data visualization.

For example, novel visualizations of stellar light curves from Kepler's first batch of data, released in June 2010, allowed members of the citizen-science project Planethunters.org to preliminarily identify 83 candidate planets that were only confirmed in last week's data release.

The same visualizations, which plot dips in the brightness of the more than 150,000 Kepler monitors, also yielded what may prove to be 47 additional candidate planets that slipped through the Kepler team's automated pipeline. Many fainter, subtler signals of smaller planets in habitable orbits around larger stars are certainly present unrecognized in the most recent dataset—borderline events that won't trigger a flag in a software routine but will catch the human eye. More people should be looking—there is a not-insignificant chance that with a bit of luck and careful observation, you could discover a potentially Earth-like world in Kepler's data even before the mission's scientists do.