Terrestrial Planet

It was 1972 and Apollo astronauts Harrison "Jack" Schmitt and Eugene Cernan had just stepped onto the moon's surface to begin collecting rock and soil samples.

The search for life beyond Earth has traditionally focused on exoplanets orbiting sun-like stars, which is a G-type star. However, low-mass stars, which are designated as K-type and M-type stars, have rapidly become a target for astrobiology, primarily due to their much longer lifetimes. This also means the habitable zone (HZ), which is the distance from a star where liquid water could exist, is much smaller than our solar system's HZ, and is referred to as the liquid water habitable zone […]

Unfortunately for science fiction fans, desert worlds outside our solar system are unlikely to host life, according to new research from the University of Washington. Scientists show that an Earth-sized planet needs at least 20 to 50% of the water in Earth's oceans to maintain a critical natural cycle that keeps water on the surface.

Earth and the course of life on Earth have been shaped by impacts. Scientists have uncovered links between massive impacts and changes in climate that altered the planet forever. But the further scientists look into the past to try to understand these changes, the more difficult it is to link them together.

The moon is Earth's only natural satellite, a rocky celestial body that orbits our planet at an average distance of about 384,000 kilometers. The most widely accepted scientific explanation for the moon's origin is the "giant impact," a high-energy collision between a Mars-sized proto-planet named Theia with the young "proto-Earth" about 4.5 billion years ago. As the newly formed moon cooled down from a hot magma ocean, layers with varying iron-content and mineral compositions crystallized to […]