Minor planets

Comet from edge of solar system killed the dinosaurs: Study

Sixty-six million years ago, a huge celestial object struck off the coast of what is now Mexico, triggering a catastrophic "impact winter" that eventually wiped out three-quarters of life on Earth, including the dinosaurs.

A pair of astronomers at Harvard say they have now resolved long-standing mysteries surrounding the nature and origin of the "Chicxulub impactor."

Distant world orbits beyond Pluto

Astronomers have spotted a distant world that orbits far beyond Pluto, in the extreme reaches of the Solar System.
The object, known informally as L91, may be in the process of gradually shifting its way inward from the Oort cloud — a reservoir of comets and other icy bodies — into the equally icy Kuiper belt. No object has ever been seen doing this.