What is the Big Bang Theory and its key concepts?
What evidence is used to support the big bang?
When was the big bang?
Big bang theory: all matter and energy was initially packed into an infinitely small point. When the point exploded, the universe began
Universe has a beginning
Started infinitely small/hot
Early universe was mainly hydrogen/helium
Universe is about 13.8 billion years old
Where do the elements come from?
Where are they created?
Why are we considered star dust? We also discuss several other topics like Who is Diego De Landa?
92 elements are naturally occurring
Protostar, massive star (elements with atomic mass up to Fe), supernova (elements heavier than Fe). Supernova explodes and the cycle repeats. We are made of elements that originally come from the stars.
What is the age of our solar system and what is the nebular theory? About 9 billion years after the Big Bang-4.8 billion years.
Nebular Theory: gravitation between materials in the nebula pulled mass inward. when pulled inward, the spin increased in accord with the conservation of angular momentum. The spinning cloud conformed to the shape of the disk, at the center is a protosun. Away from the center, planetesimals formed. They accreted more matter and became planets. 99.98% of the matter in the universe is the sun Don't forget about the age old question of What is diatomic?
What is a planet (and how do they evolve) and why is Pluto no longer considered one?
Planet: must orbit a star, be roughly spherical in shape, and clear its neighborhood of other objects. Pluto is no longer a planet because it never cleared its neighborhood of other objects
Compare and contrast the terrestrial planets with the gas/ice giants?
Terrestrial planets: shell of rock around a metallic iron alloy core. Gas giants are mostly gas or ice and are very large
How is it thought our moon formed?
A collision into Earth produced a ring of debris that eventually stuck together to become the moon
What are the systems that make the earth system?
Hydrosphere: all of the water on Earth, no matter the state
Geosphere: the solid part of the earth (land and rock)
Atmosphere: the layer of gas around the earth
Biosphere: all living things on earth and their environment
How and why is earth subdivided into layers (and what are they) and how can we probe the inner depths of our planet?
Crust: (oceanic and continental) the rock that makes up the outermost layer of the earth
Mantle: (upper and lower) the largest layer, covers the core (2885 km thick) Outer Core: (between 2900 and 5155 km deep) liquid iron alloy
Inner core: (depth of 5155 km to earth’s center at 6371 km) solid iron alloy
Separated since the compositions differ from one another. Probe the inner depths due to seismic waves If you want to learn more check out what is exotoxins?
Helio vs geocentric model
Heliocentric: the sun lies at the center of the universe while the earth and other planets orbit around it
Geocentric: earth sits motionless at the center of the universe while the moon and the planets whirl around it, and everything lies in a revolving globe of stars
Sound and light travel in waves. Movement causes the frequency or wavelength to change, which in turn changes the sound or color. Red=moving away, blue=moving towards. Everything is red, therefore everything in moving away and the universe is expanding Don't forget about the age old question of what are the Phases of matter?
Age of earth and the universe:
Universe: 13.8 billion, Earth: 65 million
Differentiation of earth into layers
Earth's magnetic field:
Dipole (north and south pole), produced by Earth’s geodynamo, melted iron moves within outer core, so the magnetic field is always changing, it protects us from most solar wind (cosmic rays)
Earth's spheres (bio,geo,etc)
What is the plate tectonics theory and what evidence helped develop the theory?
Earth’s surface consists of about 20 plates that move about one another. Continental drift, interactions at the plate’s boundaries cause volcanos, earthquakes, etc We also discuss several other topics like what is Chromatophilic substance (Nissl Bodies)?
What do the plates in the theory consist of and in what way and how fast do they move?
Lithosphere: portion of the earth that behaves rock like. They “float” on the asthenosphere. Move about 10-15 cm a year
What are the different plate boundaries and what are the key features of each? Divergent: 2 plates move away from one another
Convergent: plates move towards each other
Transform: plates slide past each other
What natural hazards (earthquakes, volcanos) are associated with what type of boundary?
Divergent: earthquakes, small volcanic eruptions
Convergent: earthquakes, large volcanic eruptions
What rock types are associated with continental and oceanic crust and how does this effect their interaction at plate boundaries?
Oceanic is less dense, consumed by the continental and melts
How did sea-floor spreading and paleo magnetism help support the theory of plate tectonics? Don't forget about the age old question of What are the concepts in the muslim tradition?
Sea floor spreading occurs when volcanic activity occurs and creates new crust at the ridge, and the older crust moves away from the ridge. It helps explain continental drift. Paleo magnetism occurs when rocks form and their crystals align with the magnetic north at the time. When the new crust is formed, the crystals align with magnetic north. Then they move away, and eventually new crust is formed with a new magnetic north.
Made 4 observations:
1. Continents fit like puzzle pieces, Pangea
2. paleoclimate data, suggested land masses were moved
3. fossils distributed in uniform patterns from land animals (south America and Africa)
4. rocks on coasts matched other coasts
Paleomagnetism shows that the Earth’s polarity has reversed multiple times in the last few million years. When reversed, the Earth is left with no magnetic shield
Lithosphere vs asthenosphere
Lithosphere: crust and upper portion of mantle (tectonic plates) Asthenosphere: lower mantle that allows the plates to move
Continental crust vs oceanic crust
Plate boundary interaction
A location at the base of the lithosphere, at the top of the mantle plume, where temperatures can cause melting. Stays in the same place while the lithosphere moves across it. (Hawaii, Yellowstone)
Ridge push and slab pull:
Ridge Push: force that drives plates away from a mid ocean ridge
Slab pull: the force down going plates apply to oceanic lithosphere at a convergent margin
What is a mineral and why are they important to understanding earth?
Mineral: naturally occurring solid formed by geological processes, has a crystalline structure, and a definable chemical composition. Must be inorganic. Minerals make up all rocks and sediment on earth
What are the common physical properties used to identify minerals?
Color, streak, hardness, cleavage, crystalline structure, amount of transparency (diaphaneity), tenacity, magnetism, luster, odor, taste, specific gravity
How are minerals formed?
Solidification of a melt, precipitation of a solution, solid-state diffusion, Biomineralization, precipitation directly from a gas
The vast majority of rock forming minerals belong to what class? silicates
What are framework silicates and why are they important?
Have a 3D framework of silicate tetrahedral with a 1:2 ratios. Comprises 75% of the Earth’s crust
What are some of the most common silicates?
Mafic, felsic, (light: feldspar group, quartz, muscovite, clay minerals) (dark: olivine, pyroxene, amphibole, biotite)
Definition of a mineral
Atomic structure and bonding types:
Structure of atoms (protons and neutrons in nucleus, electrons orbit)
Ionic: loan electrons, fairly weak, metal and nonmetal
Covalent: nonmetals share electrons, strong attraction
Metallic: metal and metal, electrons move freely
Van der waals: very weak, neutral atoms and molecules arise due to polarization
Formation of minerals
Physical properties used to identify minerals
Mineral classes (focus on silicates):
Mafic (simpler structure, dark colored, more Fe and Mg) Felsic (complex structure, light colored)
Definition of a rock
Coherent naturally occurring solid that consists of an aggregate of minerals or a body of glass
Igneous: forms from molten material
Sedimentary: form from cementation or precipitation
Metamorphic: pre-existing rocks who have gone through extreme heat/pressure Tools to investigate rocks
Rock hammer, hand lens, thin sections (thin slices of rock, polarized light)