TNO Niku

Space Missions

Retrograde Rock "Niku" Defies Orbital Trend

The discovery of trans-Neptunian object 2011 KT19 in a strange orbit deepens a key mystery in the outer solar system.

And Lo - A Tail!

Explore the Night with Bob King

Comet PanSTARRS 2016's Historic Flyby of Earth

Not one, but two, possibly related comets will make exceptionally close flybys of Earth on March 21–22. Here's what we know and a guide on how to see them.