The researchers' idea that Earth once had rings comes from reconstructions of Earth's plate tectonics from the Ordovician period—which ran between 485.4 million years and 443.8 million years ago ...

The Ordovician period and its impact spike correspond closely with a period of intense cold for our planet known as the Hirnantian glaciation—or, more dramatically, as the Hirnantian Icehouse.

The Ordovician period is notable for the Great Ordovician Biodiversification Event, a time when life on Earth experienced a remarkable evolutionary expansion.

During the Ordovician Period, a time of significant changes for Earth’s life-forms, plate tectonics and climate, the planet experienced a peak in meteorite strikes.

If you were to look up from Earth some 466 million years ago, you might have seen a gleaming ring stretching across the sky, some scientists say.

Long before the dawn of humans, dinosaurs, insects or even trees, a cascade of unfortunate events threatened to end life on earth. During the Ordovician Period, around 485 to 444 million years ago, ...

A recent study published in the journal Earth and Planetary Science Letters reveals evidence that Earth may have had a ring similar to Saturn’s around 466 million years ago, during the Ordovician ...

Armored and jawless Jawless fishes from the Ordovician Period — 488.3 million to 443.7 million years ago — are called ostracoderms, after their armored skin, and most of them are known from ...

Exceptionally well-preserved fossils of tiny worms, starfish, sponges, barnacles and other creatures with no modern parallel discovered at a quarry in Wales are painting a picture of life on Earth ...

The earliest fossil evidence for sharks or their ancestors are a few scales dating to 450 million years ago, during the Late Ordovician Period. “Shark-like scales from the Late Ordovician have been ...

The Ordovician period and its impact spike correspond closely with a period of intense cold for our planet known as the Hirnantian glaciation—or, more dramatically, as the Hirnantian Icehouse.

During the Ordovician Period, a time of significant changes for Earth’s life-forms, plate tectonics and climate, the planet experienced a peak in meteorite strikes.