New Horizons took pictures of all of Pluto’s five known moons during its encounter last summer, and now decent images of all of them are available! Some are much more visible than others; viewing conditions were not equally good for all of them, of course. And with the arrival of images of Kerberos, the New Horizons team now has the full set and has put together a family photo, adjusted to show their relative scales:
They’re weird, lumpy looking objects, bearing scars of past interactions. Kerberos is reminiscent of Comet 67P/Churyumov-Gerasimenko — rubber-ducky-shaped. As the Rosetta probe has now returned information strongly suggesting that 67P/Churyumov-Gerasimenko is actually the merged remains of two older objects, perhaps the same is true of Kerberos. With so many moons in a relatively small space, perhaps we are seeing the remains of what was once an even more complex system, where moonlets devoured other moonlets to spawn the current moons of Pluto. Food for thought?