NASA's Kepler telescope is permanently on the lookout for celestial objects of interest, and its latest discovery is a small one. A small planet, to be exact -- in fact, the smallest its encountered during its search. Kepler-37b is a tad larger than our heavenly dance partner, the Moon, and whizzes round a star much like our Sun, with two larger planets in its system for company. NASA's issuing back pats all round, as finding Kepler-37b has highlighted "the precision of the Kepler instrument" (although admittedly, the star's behavior was favorable), and suggests there are many more humble worlds of similar size awaiting our detection. It's unlikely any aliens call Kepler-37b home: it's thought to be rocky, with no atmosphere, and hugs its sun in a 13-day orbit cycle, meaning surface temperature is terribly high. Still, an achievement for Kepler, no doubt, but what we really want it to find is a planet home to beings who can explain the plot-line of Prometheus. We're still a little confused.