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

Could we intercept interstellar comet C/2019 Q4 Borisov?

When 'Oumuamua passed through our solar system two years ago, it set off a flurry of excitement in the astronomical community. Here was the first-ever interstellar object that be observed by human trackers, and the mysteries ...

Newly discovered comet is likely interstellar visitor

A newly discovered comet has excited the astronomical community this week because it appears to have originated from outside the solar system. The object—designated C/2019 Q4 (Borisov) - was discovered on Aug. 30, 2019, ...

All comets in the solar system might come from the same place

All comets might share their place of birth, new research says. For the first time ever, astronomer Christian Eistrup applied chemical models to fourteen well-known comets, surprisingly finding a clear pattern. His publication ...

Hints of a volcanically active exomoon

A rocky extrasolar moon (exomoon) with bubbling lava may orbit a planet 550 light-years away from us. This is suggested by an international team of researchers led by the University of Bern on the basis of theoretical predictions ...

Wind mystery inside gas giant Saturn begins to unravel

A new study argues that Saturn's interior flows like honey due to its magnetic field, which may help solve the mystery of why the planet's powerful winds stop 8,500km inside the giant gas planet.

Newly discovered giant planet slingshots around its star

Astronomers have discovered a planet three times the mass of Jupiter that travels on a long, egg-shaped path around its star. If this planet were somehow placed into our own solar system, it would swing from within our asteroid ...

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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