In Depth | Sun – NASA Solar System Exploration
In Depth The Sun is a 4.5 billion-year-old yellow dwarf star – a hot glowing ball of hydrogen and helium – at the center of our solar system. It’s about 93 million miles (150 million kilometers) from Earth and …
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 | Our Solar System – NASA Solar System Exploration
The planetary system we call home is located in an outer spiral arm of the Milky Way galaxy. Our solar system consists of our star, the Sun, and everything bound to it by gravity – the planets Mercury, …
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.
Jupiter - NASA Solar System Exploration
Sep 3, 2025 · Jupiter is the fifth planet from the Sun, and the largest in the solar system – more than twice as massive as the other planets combined.
The Kuiper Belt should not be confused with the Oort Cloud, which is a thousand times more distant. In 1950, astronomer Jan Oort proposed that certain comets come from a vast, extremely distant …
In Depth | Earth's Moon – NASA Solar System Exploration
The brightest and largest object in our night sky, the Moon makes Earth a more livable planet by moderating our home planet's wobble on its axis, leading to a relatively stable climate. It also causes …
In Depth | Kuiper Belt – NASA Solar System Exploration
Size and Distance The Kuiper Belt is one of the largest structures in our solar system – others being the Oort Cloud, the heliosphere, and the magnetosphere of Jupiter. Its overall shape is like a puffed-up …
Planet Compare – NASA Solar System Exploration
Oct 21, 2025 · 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 | Perseids – NASA Solar System Exploration
Swift-Tuttle takes 133 years to orbit the Sun once. It was Giovanni Schiaparelli who realized in 1865 that this comet was the source of the Perseids. Comet Swift-Tuttle last visited the inner solar system in …