Universe - The Infinite Frontier 20: Planet Earth
Earth
A hot beginning
When studying, scientists enjoy to compare our planet Earth to the other planets in the solar system.
Physics and chemistry operate the same on all different planets, other planets have these processes, we learn by looking out into space at other worlds and we even learn a it more of how we the processes work.
Solar system began in a swirling tempest of gas and dust. Unique planets were born from this.
North Magnetic Pole isn’t in the same place as the North Geometric pole (the axis that the Earth Spins on). North Magnetic Pole continually moves, not a fixed point.
All planets (including Earth) were formed by colliding bodies of dust in the solar system. (Generating a large amount of heat).
3 main subdivisions of the Earth are : Core (liquid Iron), Mantle of rock, Crust (Lower Density)
Magnetic field is a result of the liquid iron core motion
This period of the Earth being crushed and created took 100 million years, there was no evidence of anything for the first 1 billion years of the Earth’s existence because of the molten rock being mixed in with what's already there
Moving plates
A subduction zone is the biggest crash scene on Earth. These boundaries mark the collision between two of the planet's tectonic plates. The plates are pieces of crust that slowly move across the planet's surface over millions of years.( japan, south of japan and chile)
Hot Land- Material Rises up from the Earth, Cooled Material sinks back into the Earth into Subduction Zones
The interior of the earth is close to its melting point, has a very low viscosity (stick, fluid in consistency due to friction). Hot and cold regions of the Earth’s crust lead to plate movement, as well as tidal waves.
Earth’s land was once a supercontinent (Pangea), lasted for 200 Million years, then became individual continents over time due to tectonic shifts (Continental Drift)
Seafloor spreading
Tectonic shifts can lead to volcanoes / Volcanism. (An Important Process where magma comes out of the Earth to Create Mountain Ranges / Hotspots such as Hawaii.)
Earth’s land movement is a dynamic process, aways new and always changing.(New Continents, Seafloor, Volcanic Process.)
Seafloor spreading: the formation of new areas of oceanic crust, which occurs through the upwelling of magma at mid ocean ridges and its outward movement on either side. The Ocean Floor visibly shows the process of tectonic movement / Seafloor Spreading.
Vocab
Seismology: Best method of determining the inner structure of the Earth. (Through Earthquakes / Tectonic shifts / Seismic Waves of Motion). Seismic Waves also reveal information about the earth’s Crust because the waves of motion created by earthquakes not only tell us about our planets interior they reveal the dynamic nature of the Earth's crust.
Dynamo Process: the process through which a rotating, convecting, and electrically conducting fluid can maintain a magnetic field over astronomical time scales.(Like Earth’s magnetic Field).
Earth is the only planet known to man that have an efficient recycling process of the core coming out onto the surface and renewing its texture
Surface and deeper
The earth has oceans and water and an atmosphere. 75% of the Earth is Covered in Ocean Waters (Largely Different from other planets in the solar system.
Earth is far enough away from the sun for the it’s water to condense from water vapor to physica liquid.
Earth's crust makes it unique among the planets so too does the thin layer of gas and liquid that clings to its surface
click to edit
Theories
We think that after the earth formed the material that made up the earth had a small amount of gas as part of the rock but as it melted it escaped
Scientists believe that in the early stages of earth history when the water was covering the ocean would be more acidic
We still don't know if most or all of the volatiles even in the case of the earth were brought in after the planet itself formed or whether a slow continuous degassing process is still happening today