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1.Big bang theory (formation of matter, expansion, cooling, first cycle of stellar formation)The Big Bang was originally proposed by Georges LeMaitre in 1927. He was a physicist and priest. The Big Bang Theory is the leading explanation about how the universe began. The universe began very hot, small, and dense superforce (The mix of the 4 cosmic forces), with no stars, atoms, form, or structure (called a "singularity"). Then about 13.8 billion years ago,spaceexpanded very quickly (thus the name "Big Bang"). This started the formation of atoms, which eventually led to the formation of stars and galaxies. This theory comes from the idea that energycondenses into mass and mass expands and is continuously expanding. The universe is expanding faster than expected, but there isn’t enough matter and energy in the universe to have sufficient gravitational pull to decelerate the expansion. The universe is still expanding today, but getting colder as well.Stars form from massive clouds of dust and gas in space. Gravity pulls the dust and gas together. As the gas falls together, it gets hot. A star forms when it is hot enough for nuclear reactions to start. This releases energy, and keeps the star hot. The outward pressure from the expanding hot gases is balanced by the force of the star's gravity. Our sun is at this stable phase in its life. Gravity pulls smaller amounts of dust and gas together, which form planets in orbit around the star. Stars do not stay the same forever. They have a finite life. What happens to them depends on their mass.
2.Cascadia subduction zone off the west coast of CanadaThe Cascadia subduction zone (also referred to as the Cascadia fault) is a convergentplate boundary that stretches from northern Vancouver Island to northern California. It is a very long, sloping subduction zone that separates the Explorer, Juan de Fuca, and Gorda plates, on the one hand, and the North American Plate, on the other. The Cascadia subduction zone runs from triplejunctions at its north and south ends. A triple junction is the point where the boundaries of three tectonic plates meet. At the triple junction each of the three boundaries will be one of 3 types - a ridge (R), trench (T) or transform fault (F). -A mid-ocean ridge is an underwatermountain system formed by plate tectonics-Oceanic trenches are topographic depressions of the sea floor, relatively narrow in width, but very long. These oceanographic features are the deepest parts of the ocean floor-