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The universe we live in is a place of vastness beyond human conception. It has principles of operation that can be divined by observation, analysis, and calculation. It is the goal of this organization to attempt to set an order to those principles in a fashion that results in the unification of the principles into a coherent calculable science.

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Geologic timescale
The geological history of Earth began 4.57 billion years ago when the planets of the Solar System were formed out of the solar nebula, a disk-shaped mass of dust and gas left over from the formation of the Sun. Initially molten, the outer layer of the planet Earth cooled to form a solid crust when water began accumulating in the atmosphere. The Moon formed soon afterwards, possibly as the result of a Mars-sized object with about 10% of the Earth's mass, known as Theia, impacting the Earth in a glancing blow. Some of this object's mass merged with the Earth and a portion was ejected into space, but enough material survived to form an orbiting moon. Outgassing and volcanic activity produced the primordial atmosphere. Condensing water vapor, augmented by ice delivered by comets, produced the oceans. As the surface continually reshaped itself, over hundreds of millions of years, continents formed and broke up. The continents migrated across the surface, occasionally combining to form a supercontinent. Roughly 750  Ma (million years ago) (ICS 2004), the earliest known supercontinent Rodinia, began to break apart. The continents later recombined to form Pannotia, 600–540  Ma (ICS 2004), then finally Pangaea, which broke apart 180 Ma (ICS 2004). The present pattern of ice ages began about 40 Ma (ICS 2004), then intensified during the Pleistocene about 3 Ma (ICS 2004). The polar regions have since undergone repeated cycles of glaciation and thaw, repeating every 40,000–100,000 years. The last glacial period of the current ice age ended about 10,000 years ago.

Did you know...

Mock mirage of the setting sun
  • ...that your watch would run slower when orbiting a black hole than it would on Earth?
  • ...that Aristotle's ideas of physics held that because an object could not move without an immediate source of energy, arrows created a vacuum behind them that pushed them through the air.
  • ...that nuclear fusion reactions are probably occurring at or above the sun's photosphere; it is a process called solar surface fusion.
Artist's depiction of the WMAP satellite measuring the Cosmic Microwave Background Radiation to help scientists understand the Big Bang
  • ...that neutron stars are so dense that a teaspoonful (5 mL) would have ten times the mass of all human world population?
  • ...that every year, the Moon moves 3.82 cm away from Earth?
  • ...that Neptune was discovered by its gravitational pull on Uranus?

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ALMA Reveals Ghostly Shape of ‘Coldest Place in the Universe’
131029 boomerang 01.jpg
ALMA is an array of 12 m- and 7 m-diameter antennas that observe the cosmos at millimetre/submillimetre wavelengths. The antennas work together to function as an interferometer, and this allows the signals from each of the antennas to be combined to simulate a telescope the size of the distance between the individual units. The array works like a zoom lens on a camera: the antennas can be repositioned so that the baseline of the simulated telescope is as small as 150 m or as large as 15 km across.
The Boomerang Nebula, called the “coldest place in the Universe,” reveals its true shape with ALMA. The background blue structure, as seen in visible light with the Hubble Space Telescope, shows a classic double-lobe shape with a very narrow central region. ALMA’s resolution and ability to see the cold molecular gas reveals the nebula’s more elongated shape, as seen in red. Credit: Bill Saxton; NRAO/AUI/NSF; NASA/Hubble; Raghvendra Sahai

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