Frozen Visitors From Afar Comets are really icy planetesimals. This means that they are the ancient leftover building blocks of the quartet […]

The Oort Cloud In 1932 the Estonian astronomer Ernst Opik (1893-1985) proposed that long-period comets came from an orbiting cloud at the outer […]

Comets are delicate and transient visitors from our Solar System’s frigid, dark twilight regions beyond the orbit of the outermost […]

The Hunt For Distant Worlds Historically, the quest to detect remote planets, inhabiting the families of alien stars beyond our […]

Icy Wanderers Comets are relic icy planetsimals. This means that they are what is left of a vast population of primordial […]

When the first hot Jupiters were detected about a generation ago, they were generally thought to be “oddballs” because we do not […]