In Depth | Earth's Moon – NASA Solar System Exploration
Earth's Moon is the only place beyond Earth where humans have set foot, so far. Earth's only natural satellite is simply called "the Moon" because people didn't know other moons existed until Galileo …
By the Numbers | Earth's Moon – 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.
Jupiter - NASA Solar System Exploration
Sep 3, 2025 · Unlike Earth’s Moon and our planet’s northern lights, the massive, shimmering auroras above Jupiter’s poles carry signatures that the planet’s largest moons leave in the atmosphere.
Mars By the Numbers - NASA Solar System Exploration
Oct 21, 2025 · Mars is the fourth planet from the Sun, and the seventh largest. It’s the only planet we know of inhabited entirely by robots.
In Depth | Our Solar System – NASA Solar System Exploration
One astronomical unit (or AU) is the distance from the Sun to Earth, or about 93 million miles (150 million kilometers). The Oort Cloud is the boundary of the Sun's gravitational influence, where …
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 – in its orbit.
In Depth | Oumuamua – NASA Solar System Exploration
The first known interstellar object to visit our solar system, 1I/2017 U1 ‘Oumuamua, was discovered Oct. 19, 2017 by the University of Hawaii’s Pan-STARRS1 telescope, funded by NASA’s Near-Earth …
In Depth | Titan – NASA Solar System Exploration
Because Titan is less massive than Earth, its gravity doesn't hold onto its gaseous envelope as tightly, so the atmosphere extends to an altitude 10 times higher than Earth's—nearly 370 miles (600 …
Io By the Numbers – NASA Solar System Exploration
May 16, 2024 · Units of Measure: SIZE COMPARISON Earth Io Io is 3.5x smaller than Earth DATE OF DISCOVERY
In Depth | Callisto – NASA Solar System Exploration
Callisto orbits about 1,170,000 miles (1,883,000 kilometers) from Jupiter and it takes about 17 (16.689) Earth days for Callisto to complete one orbit of Jupiter.