Engineering

What really matters in multi-story building design?

The impact of multi-story building design considerations on embodied emissions, cost, and operational energy has been revealed for the first time. Using a model, researchers estimate that 28% to 44% of yearly heating and ...

Energy & Green Tech

Doing the math on a solar-powered future

Physicist Anders Carlsson, at Washington University in St. Louis, and Sid Redner of the Santa Fe Institute have created a new mathematical model to describe the most reliable, efficient and cost-effective way to harness solar ...

Energy & Green Tech

EU races to lead green tech battle against US, China

The EU on Thursday announced plans to push the bloc's businesses to produce more clean technology in Europe to challenge state-backed competition from the United States and China.

Engineering

The benefits of floatovoltaics: Putting solar panels on reservoirs

An international team of environmental scientists is touting the benefits of solar panels on floating platforms atop reservoirs and other bodies of water. In their paper published in the journal Nature Sustainability, the ...

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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