5th planet found in same solar system

This is cool. The fifth planet found around 55 Cancri is in the habitable zone of the star, so any moons may have water.

Perhaps the coolest part of this whole discovery: the planet orbits its parent star once every 260 days. This places it within its star's habitability zone, where liquid water can be present. It's a little closer than our Earth is to the Sun, but its star is also a little fainter, so it all evens out.

Obviously, this rules out the planet itself, but it could have a collection of moons, just like Saturn. Instead of Saturn's icy moons, this 5th planet of 55 Cancri could have ocean moons.

Finding this planet was an enormous challenge. The discoverers have been making observations of 55 Cancri for 18 years, before the first extra solar planets were ever found. They had to make more than 320 velocity measurements to disentangle the 5 planets from the data.