Solar System

The Solar System is the gravitationally bound system of the Sun and the objects that orbit it, either directly or indirectly. Of the objects that orbit the Sun directly, the largest are the eight planets, with the remainder being smaller objects, the dwarf planets and small Solar System bodies. Of the objects that orbit the Sun indirectly—the natural satellites—two are larger than the smallest planet, Mercury. The Solar System formed 4.6 billion years ago from the gravitational collapse of a giant interstellar molecular cloud. The vast majority of the system's mass is in the Sun, with the majority of the remaining mass contained in Jupiter. The four smaller inner system planets, Mercury, Venus, Earth and Mars, are terrestrial planets, being primarily composed of rock and metal. The four outer system planets are giant planets, being substantially more massive than the terrestrials.

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June’s Night Sky Notes: Seasons of the Solar System

Scientists Say They’ve Found a Dwarf Planet Very Far From the Sun

China extends its reach into the Solar System with launch of asteroid mission

Passing Stars Could Have a Significant Impact on the Future of our Solar System

Was Planet Nine exiled from the solar system as a baby?

Astronomers think they've discovered a new dwarf planet in our solar system

Tiny Asteroids, Big Threats: How JWST is Uncovering Hidden Worlds in Our Solar System

Milestone discovery: James Webb telescope discovers frozen water around a distant, sunlike star. The discovery of water ice around a distant star is allowing scientists to study how the key ingredient for life is delivered to young planets beyond our solar system.

Scientists Discover New Dwarf Planet in Solar System, Far Beyond Pluto

New dwarf planet spotted at the edge of the solar system

Our Solar System May Have a New Planetary Sibling: Another Dwarf Planet

Possible Dwarf Planet Discovered at Solar System’s Edge

China is readying a mission to two rocky bodies in our solar system

Risk of a star destroying the solar system is higher than expected

Astronomers spot possible Planet Nine in data spanning 23 years | Old satellite data points to potential ninth planet in our solar system

New Horizons Helps Map the Hot Clouds of Interstellar Gas All Around the Solar System

Strongest hints yet of biological activity outside the solar system: « Astronomers have detected the most promising signs yet of a possible biosignature outside the solar system, although they remain cautious. »

New JWST observations of 'trans-Neptunian objects' could help reveal our solar system's past

Mysterious Glowing Structure Discovered Near Solar System

Huge, Invisible Cloud Discovered Just 300 Light-Years From The Solar System