Frontiers is an open-access digital publisher, making quality peer-reviewed research quickly free to read. In the physical sciences, journals span physics, astronomy, earth science, and space. Frontiers in Astronomy and Space Sciences covers everything from astroparticles to cosmology, including planetary and exoplanet research, Frontiers in Space Technologies advances the engineering behind space missions and planetary science; together the two journals form a connected resource for the global space research community.