In the last 40,000 years, there have been at least ten gigantic landslides of more than 100 cubic kilometers in the North Atlantic ocean alone. Each of these was capable of producing waves tens to hundreds of meters in height and according to a new report, this is only one of the many possible planetary disasters that could cause extinction.
The precise conditions that cause rivers to form branches have long been a mystery, until now. A new study pinpoints two opposing physical forces that work together to produce the intricate patterns of rivers. This could help scientists understand rivers at all scales, even on other worlds.
Earth’s moon might have emerged from a long-vanished ring system, akin to the rings still encircling Saturn, and this could apply to many of the satellites orbiting other planets. The bulk of the regular satellites in the Solar System might have formed this way, instead of taking shape simultaneously with the planet as a direct result of planet formation.
One of the strangest moons in the Solar System is Saturn’s Iapetus, which features an enormous equatorial mountain ridge and spiky belt that rises 12 miles above the moon’s surface may have all been the result of a single impact.
Most orbiting satellites point down towards Earth, but the satellites of the Constellation Observing System for Meteorology look sideways. Ionosphere and Climate (COSMIC) look towards the curving horizon in order to track the dozens of satellites that are part of the Global Positioning System. By tracking their radio signals, COSMIC is providing atmospheric data that enhances weather forecasts and climate models.
These images showcase the fine-scale structure of the atmosphere of Uranus, and contain vastly more detail than other images. The images were taken by the adaptive-optics-equipped telescope, the Keck II, which employed its NIRC2 camera.
One of the widest accepted models for the Moon’s formation states that a renegade, Mars-sized planet, named Theia, slammed into Earth 4.5 billion years ago, and pushed up debris that would eventually coalesce into a satellite. This theory has been able to predict and explain many facts, like the mass of Earth and the Moon, but it also says that most of the lunar-forming debris stemmed from Theia, not proto-Earth. Theia is thought to have originated from a different part of the Solar System, with different elemental isotopes, which conflicts with some of the more sensitive measurements of the past decade showing that rocks from Earth and the Moon have identical isotopic ratios of oxygen, titanium, chromium, and tungsten.
Saturn’s odd mix of mid-sized satellites are among the strangest in the outer Solar System. With widely varying densities and locations, measuring between 300 to 1,500 kilometers in diameters, these moons have some distinctive characteristics. Some are made up almost completely of ice, and some are rockier and geologically active. Some even show evidence of submoons and rings.