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 planets being found.
The Solar System and Beyond is Awash in Water
Apr 6, 2015 · Understanding the distribution of water in our solar system tells us a great deal about how the planets, moons, comets and other bodies formed 4.5 billion years ago from the disk of gas and dust that surrounded our sun.
In Depth | Kuiper Belt – NASA Solar System Exploration
The Kuiper Belt is a large region in the cold, outer reaches of our solar system beyond the orbit of Neptune. It's sometimes called the "third zone" of the solar system. Astronomers think there are millions of small, icy objects in this region – including hundreds of thousands that are larger than 60 miles (100 kilometers) wide.
In Depth | Pluto – NASA Solar System Exploration
Dwarf planet Pluto is a member of a group of objects that orbit in a disc-like zone beyond the orbit of Neptune called the Kuiper Belt. This distant realm is populated with thousands of miniature icy worlds, which formed early in the history of our solar system about 4.5 billion years ago.
What is a Planet? | Planets – NASA Solar System Exploration
A planet is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit.
In Depth | Oumuamua – NASA Solar System Exploration
It will travel beyond Saturn’s orbit in January 2019; as it leaves our solar system, ‘Oumuamua will head for the constellation Pegasus. Preliminary orbital calculations suggest that the object came from the approximate direction of the bright star Vega, in the northern constellation of Lyra.
In Depth | Europa – NASA Solar System Exploration
So while Europa is only one-fourth the diameter of Earth, its ocean may contain twice as much water as Earth’s global ocean. Europa’s ocean is considered one of the most promising places in the solar system to look for life beyond Earth.
In Depth | 1P/Halley – NASA Solar System Exploration
Halley's backward, or retrograde, motion is unusual among short-period comets, as its greatest distance from the Sun (aphelion) is beyond the orbit of Neptune. Halley's orbit period is, on average, 76 Earth years.
Asteroids, Comets & Meteors - NASA Solar System Exploration
Asteroids and comets – and the meteors that sometimes come from them – are leftovers from the formation of our solar system 4.6 billion years ago.
In Depth | Ceres – NASA Solar System Exploration
Dwarf planet Ceres is the largest object in the asteroid belt between Mars and Jupiter, and it's the only dwarf planet located in the inner solar system. It was the first member of the asteroid belt to be discovered when Giuseppe Piazzi spotted it in 1801.