Terrestrial Planet

Dreams of finding a sort of Earth 2.0 motivate much of the thinking around the search for exoplanets. But there is more to exoplanet science than searching for potentially habitable worlds. Scientists need a deeper understanding of the overall exoplanet population to understand the cosmos.

Long before dinosaurs ruled the continents and modern crocodiles first appeared, their ancestors were already going through a decisive phase in their evolutionary history. It was in this ancient world, shortly after the greatest mass extinction in Earth's history, that a new species of fossil reptile was discovered in Brazil's inland Rio Grande do Sul state.

Researchers in the U.S. have carried out the most stringent tests to date of the idea that an ultraviolet glow in the atmospheres of giant planets could partly arise through the indirect interaction between dark matter and ordinary matter. Led by Carlos Blanco at Penn State University and Rebecca Leane at the SLAC National Accelerator Laboratory, the team's results place some of the tightest constraints yet on the strength of this interaction.

In a major milestone in the search for life on other planets, astronomers have detected, for the first time, an atmosphere surrounding an Earth-like, rocky planet orbiting within the habitable zone of another star. The finding provides the strongest evidence yet that worlds with conditions similar to Earth in composition and temperature, with the potential to support life, could exist beyond our solar system.

A Southwest Research Institute-led study has proposed a connection between a specific collision in the main asteroid belt and an inner-solar-system-wide bombardment episode that may have had measurable biological and geological consequences on Earth. The research suggests that the catastrophic breakup of the Eulalia parent body could be linked to an impact shower that struck the terrestrial planets about 800 million years ago. The work is published on the arXiv preprint server.