It's just one data point among the 1,235 potential worlds identified by NASA's Kepler planet-hunting probe, but you can't help noticing it on a graph. The planetary candidate known as KOI 326.01 sticks out as the one object that's estimated to be the size of Earth or smaller, with an average temperature that's lower than water's boiling point. If scientists confirm that what they're seeing actually exists, KOI 326.01 could go down as the closest analog to our own planet in the current crop of Kepler data. But that's a big if.