Exoplanetary systems are very different from our solar system—at least, from what astronomers have been able to observe so far. Most of these systems have, for example, huge gas giant planets orbiting closer to their stars than Mercury is orbiting around the Sun. That characteristic alone would destroy every Earth-like planet in the inner parts of those systems. As more and more exoplanets have been discovered, though, it seems likely that planetary systems more similar to our own will be found as well.