Solar System
hideThe 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.
For more information about Solar System, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
News tagged with solar
Solar Roadways Awarded DOT Contract to Pave Roads with Solar Cells
Sep 07, 2009 |
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(PhysOrg.com) -- In a first step toward turning highways into energy-generating solar panels, the Sagle, Idaho-based startup Solar Roadways has recently received a $100,000 grant from the US Department of ...
LCROSS Impact Finds Water on the Moon
Space & Earth / Space Exploration
Nov 13, 2009 |
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(PhysOrg.com) -- The argument that the moon is a dry, desolate place no longer holds water. Secrets the moon has been holding, for perhaps billions of years, are now being revealed to the delight of scientists ...
$21 Billion Orbiting Solar Array will Beam Electricity to Earth
Sep 15, 2009 |
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(PhysOrg.com) -- The Japanese are preparing to develop a two trillion yen (approximately $21 billion USD) space solar project that will beam electricity from space in the form of microwaves or lasers to around ...
Scientists Reproduce a Building Block of Life in Laboratory
Nov 06, 2009 |
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(PhysOrg.com) -- NASA scientists studying the origin of life have reproduced uracil, a key component of our hereditary material, in the laboratory.
Lower-cost solar cells to be printed like newspaper, painted on rooftops
Nanotechnology / Nanomaterials
Aug 24, 2009 |
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Solar cells could soon be produced more cheaply using nanoparticle "inks" that allow them to be printed like newspaper or painted onto the sides of buildings or rooftops to absorb electricity-producing sunlight.
Mystery of the Solar Tsunami -- Solved (w/ Video)
Nov 19, 2009 |
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(PhysOrg.com) -- Sometimes you really can believe your eyes. That's what NASA's Solar Terrestrial Relations Observatory (STEREO) is telling researchers about a controversial phenomenon on the sun known as ...
Gravitational Space Corridors Could Slash Space Travel Costs (w/ Video)
Space & Earth / Space Exploration
Sep 16, 2009 |
4.6 / 5 (29) |
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(PhysOrg.com) -- Scientists studying space travel possibilities have proposed that gravitational space corridors could be used by spacecraft, in much the same way as ships use ocean currents. Taking advantage ...
Solar power generation around the clock
Nov 05, 2009 |
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(PhysOrg.com) -- A Californian company, SolarReserve, is developing a solar power system that can store seven hours' worth of solar energy by focusing mirrors onto millions of gallons of molten salt, allowing ...
Innovation puts next-generation solar cells on the horizon
Dec 01, 2009 |
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In a world first, a Monash University-led international research team has developed an innovative way to boost the output of the next generation of solar cells.
Sharp Develops Solar Cell with World's Highest Conversion Efficiency of 35.8%
Oct 22, 2009 |
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Sharp Corporation has achieved the world's highest solar cell conversion efficiency (for non-concentrator solar cells) of 35.8% using a triple-junction compound solar cell.
Are Sunspots Disappearing?
Space & Earth / Space Exploration
Sep 03, 2009 |
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The sun is in the pits of the deepest solar minimum in nearly a century. Weeks and sometimes whole months go by without even a single tiny sunspot. The quiet has dragged out for more than two years, prompting ...
A Superbright Supernova That’s the First of Its Kind
Dec 02, 2009 |
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(PhysOrg.com) -- An extraordinarily bright, extraordinarily long-lasting supernova named SN 2007bi, snagged in a search by a robotic telescope, turns out to be the first example of the kind of stars that first ...
The Stars My Destination
Space & Earth / Space Exploration
Nov 10, 2009 |
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The Voyager spacecraft are now in the outermost layer of the heliosphere, traveling toward interstellar space - the first man-made spacecraft to travel such a vast distance from Earth.
Scientists Explore Galactic Frontier, Release First-Ever All-Sky Map (w/ Video)
Space & Earth / Space Exploration
Oct 15, 2009 |
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(PhysOrg.com) -- NASA's Interstellar Boundary Explorer, or IBEX, spacecraft has made it possible for scientists to construct the first comprehensive sky map of our solar system and its location in the Milky ...
Japan eyes solar station in space as new energy source
Nov 08, 2009 |
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It may sound like a sci-fi vision, but Japan's space agency is dead serious: by 2030 it wants to collect solar power in space and zap it down to Earth, using laser beams or microwaves.
