
Privacy
Sun | |
---|---|
State | |
Country | |
Capital | |
Population | 0 |
The Sun is the star at the center of the Solar System. It is a nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy mainly as light and infrared radiation. It is by far the most important source of energy for life on Earth. Its diameter is about 1.39 million kilometres (864,000 miles), or 109 times that of Earth, and its mass is about 330,000 times that of Earth. It accounts for about 99.86% of the total mass of the Solar System.
Roughly three quarters of the Sun's mass consists of hydrogen (~73%); the rest is mostly helium (~25%), with much smaller quantities of heavier elements, including oxygen, carbon, neon, and iron.The Sun is a G-type main-sequence star (G2V) based on its spectral class. As such, it is informally and not completely accurately referred to as a yellow dwarf (its light is closer to white than yellow). It formed approximately 4.6 billion years ago from the gravitational collapse of matter within a region of a large molecular cloud. Most of this matter gathered in the center, whereas the rest flattened into an orbiting disk that became the Solar System. The central mass became so hot and dense that it eventually initiated nuclear fusion in its core. It is thought that almost all stars form by this process.
Brisbane | |
---|---|
State | Queensland |
Country | Australia |
Capital | |
Population | 2190000 |
Postcode | 4000 |
Brisbane ( (listen) BRIZ-bən) is the capital of and the most populated city in the Australian state of Queensland, and the third most populous city in Australia. Brisbane's metropolitan area has a population of over 2.5 million, and the South East Queensland metropolitan region, centred on Brisbane, encompasses a population of more than 3.6 million. The Brisbane central business district stands on the historic European settlement and is situated inside a peninsula of the Brisbane River, about 15 kilometres (9 miles) from its mouth at Moreton Bay, a bay of the Coral Sea. The metropolitan area extends in all directions along the hilly floodplain of the Brisbane River Valley between Moreton Bay and the Taylor and D'Aguilar mountain ranges. It sprawls across several of Australia's most populous local government areas (LGAs)—most centrally the City of Brisbane, which is by far the most populous LGA in the nation. The demonym of Brisbane is "Brisbanite", whilst common nicknames include "Brissy", "River City" and "Brisvegas".One of the oldest cities in Australia, Brisbane was founded upon the ancient traditional lands of the Jagera people, including the Turrbal group, who named the area Meanjin. Named after the Brisbane River on which it is located—which in turn takes its name from Scotsman Sir Thomas Brisbane, the Governor of New South Wales at the time of the city's founding—the area was chosen as a place for secondary offenders from the Sydney Colony. The Moreton Bay penal settlement was founded in 1824 at Redcliffe, 28 kilometres (17 mi) north of the central business district, but was soon abandoned and moved to North Quay in 1825, opening to free settlement in 1842.