Its gravity holds the solar system together, keeping everything in its orbit. Almost all (99.8%) of the mass in the solar system is contained within the Sun.
Solar System Exploration
Sep 30, 2025 · Our solar system orbits the center of the galaxy at about 515,000 mph (828,000 kph). It takes about 230 million years to complete one orbit around the galactic center.
The orbits (including the spiral transfers between science orbits) are designed so that even if control is lost for as long as 28 days, the flight system will remain safe.
The Sun By the Numbers - NASA Solar System Exploration
Oct 21, 2025 · The Sun is the star at the heart of our solar system. Its gravity holds the solar system together, keeping everything – from the biggest planets to the smallest bits of debris – …
Dawn’s quest to understand the conditions that ex-isted when our solar system formed provides context for the observation of planetary systems around other stars.
In Depth | Our Solar System – NASA Solar System Exploration
Beyond our own solar system, there are more planets than stars in the night sky. So far, we have discovered thousands of planetary systems orbiting other stars in the Milky Way, with more …
The Cassini spacecraft will make more than 70 orbits of Saturn, studying the planet, its magne- tosphere, rings, and moons. The European Space Agency’s Huygens probe descends to …
In March 2004, a team of astronomers announced the discovery of a planet-like transneptunian object orbiting the Sun at an extreme distance, in one of the coldest known regions of our solar …
In Depth | Kore – NASA Solar System Exploration
NASA’s real-time science encyclopedia of deep space exploration. Our scientists and far-ranging robots explore the wild frontiers of our solar system.
In Depth | Ganymede – NASA Solar System Exploration
Ganymede orbits the Sun along with Jupiter and its other satellites every 12 Earth years. Ganymede, Io, and Europa are in what is called a resonance – every time Ganymede orbits …