Related topics: planets · nasa · earth · orbit · asteroid

Newborn gas planets may be surprisingly flat, says new research

A new planet starts its life in a rotating circle of gas and dust, a cradle known as a protostellar disk. My colleagues and I have used computer simulations to show that newborn gas planets in these disks are likely to have ...

Ground-based lasers could accelerate spacecraft to other stars

The future of space exploration includes some rather ambitious plans to send missions farther from Earth than ever before. Beyond the current proposals for building infrastructure in cis-lunar space and sending regular crewed ...

Saturn's largest moon most likely uninhabitable

A study led by Western astrobiologist Catherine Neish shows the subsurface ocean of Titan—the largest moon of Saturn—is most likely a non-habitable environment, meaning any hope of finding life in the icy world is dead ...

Lunar science is entering a new active phase

For the first time since 1972, NASA is putting science experiments on the moon in 2024. And thanks to new technologies and public-private partnerships, these projects will open up new realms of scientific possibility. As ...

Cosmic dark matter web detected in Coma cluster

The Subaru Telescope has spotted the terminal ends of dark matter filaments in the Coma cluster stretching across millions of light years. This is the first time that strands of the cosmic web spanning the entire universe ...

Small satellite may shape centaur rings

The unique two thin rings around the Centaur Chariklo could be shaped by an even smaller satellite. Chariklo is a Centaur, which are small bodies similar to asteroids in size but to comets in composition, that revolve around ...

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Solar System

The Solar System[a] consists of the Sun and those celestial objects bound to it by gravity, all of which formed from the collapse of a giant molecular cloud approximately 4.6 billion years ago. The Sun's retinue of objects circle it in a nearly flat disc called the ecliptic plane, most of the mass of which is contained within eight relatively solitary planets whose orbits are almost circular. The four smaller inner planets; Mercury, Venus, Earth and Mars, also called the terrestrial planets, are primarily composed of rock and metal. The four outer planets, Jupiter, Saturn, Uranus and Neptune, also called the gas giants, are composed largely of hydrogen and helium and are far more massive than the terrestrials.

The Solar System is also home to two main belts of small bodies. The asteroid belt, which lies between Mars and Jupiter, is similar to the terrestrial planets as it is composed mainly of rock and metal. The Kuiper belt (and its subpopulation, the scattered disc), which lies beyond Neptune's orbit, is composed mostly of ices such as water, ammonia and methane. Within these belts, five individual objects, Ceres, Pluto, Haumea, Makemake and Eris, are recognised to be large enough to have been rounded by their own gravity, and are thus termed dwarf planets. The hypothetical Oort cloud, which acts as the source for long-period comets, may also exist at a distance roughly a thousand times beyond these regions.

Within the Solar System, various populations of small bodies, such as comets, centaurs and interplanetary dust, freely travel between these regions, while the solar wind, a flow of plasma from the Sun, creates a bubble in the interstellar medium known as the heliosphere, which extends out to the edge of the scattered disc.

Six of the planets and three of the dwarf planets are orbited by natural satellites, usually termed "moons" after Earth's Moon. Each of the outer planets is encircled by planetary rings of dust and other particles.

This text uses material from Wikipedia, licensed under CC BY-SA