Blog

Explore the forces that slowly reshape the Solar System, from planetary orbits and asteroid impacts to the Sun’s evolution and distant gravitational perturbations.

Learn how the asteroid belt formed, why its rocks stay in orbit, and what keeps it from becoming a planet.

Explore why Mercury, Venus, Earth, and Mars formed as rocky planets, and how temperature, gravity, and early solar system chemistry shaped them.

Explore how our Solar System stacks up against thousands of known star systems in terms of planets, architecture, stability, and formation.

Discover what defines the solar system’s edge, from the heliosphere and heliopause to the Oort Cloud and the farthest known worlds.

Learn how astronomers find exoplanets using transit, radial velocity, imaging, and more, plus how they confirm each discovery.

Learn how astronomers measure planet mass using radial velocity, transits, timing, and imaging, plus the limits that shape every estimate.

Learn how astronomers name planets, moons, asteroids, comets, and dwarf planets using International Astronomical Union standards.

Learn how dwarf planets differ from planets, asteroids, and moons, with clear examples from Pluto, Ceres, Eris, Haumea, and Makemake.

Learn which planet is closest to the Sun, why Mercury holds that title, and how its extreme orbit shapes conditions there.