The “Planet Earth Report” connects you to headline news on the science, technology, discoveries, people and events changing our planet and the future of the human species.
We didn’t know what the Sun looked like in its first billion years, and it’s super important because it likely changed how Venus’ atmosphere evolved and how quickly it lost water, said Prabal Saxena, an astrophysicist at NASA’s Goddard Space Flight Center. “It also probably changed how quickly Mars lost its atmosphere, and it changed the atmospheric chemistry of Earth.”
The largest extinction in Earth’s history marked the end of the Permian period, some 252 million years ago. Long before dinosaurs, our planet was populated with plants and animals that were mostly obliterated after a series of massive volcanic eruptions in Siberia. Fossils in ancient seafloor rocks show a thriving and diverse marine ecosystem, then a swath of corpses. Some 96 percent of marine species were wiped out during the “Great Dying,” followed by millions of years when life had to multiply and diversify once more.
“Essentially it’s a flipping over of the entire ocean, rather than an injection of surface water on a one-way trip from the surface to the deep,” said Earle Wilson, an oceanographer at the University of Washington about winter ice on the surface of Antarctica’s Weddell Sea that occasionally forms an enormous hole, known as a polynya. A hole that appeared in 2016 and 2017 drew intense curiosity from scientists and reporters. Though even bigger gaps had formed decades before, this was the first time oceanographers had a chance to truly monitor the unexpected gap in Antarctic winter sea ice.
In the mid-1980s, a group of American archaeologists pored over satellite images trying to understand what had become of the Mayan civilization that had once ruled over Mexico’s Yucatan Peninsula, discovered a pattern: a near-perfect ring of sinkholes -cenotes- about 200km across,, encircling the Yucatecan capital, Merida, and port towns of Sisal and Progreso. A pattern created by an ancient asteroid explosion that may yield clues to the lost ocean and atmosphere of Mars.
