What causes the tectonic plates to move?
Tectonic plate movement occurs at fault lines where neighboring plates meet. Convection currents in the mantle constantly cycle new crust from the mantle onto the surface of the crust while older pieces of crust submerge back into the mantle. This process is constantly occurring on Earth, so the plates are currently being shifted as the crust is getting pushed further and further over as new crust is being born. Evidence can be found of this in examples like the Hawaiian islands, which can be seen to move west at approximately 7 centimeters each year. 8. Why is Venus so hot? Venus is so hot for a variety of reasons. The first is that it is so close to the Sun, which means it receives more intense sunlight which raises surface temperatures. For example, if Earth orbited the Sun at the distance that Venus did, the more intense sun rays would increase surface temperatures by an average of 30 degrees Celsius. Due to its hotter surface temperatures by nature of its proximity to the Sun, many other factors come into play that affect its atmosphere which further affect the temperature. For example, the hotter surface temperature and close orbit to the Sun, no significant water accumulations or water oceans ever formed on Venus. Because of this, the CO2 in Venus’ early stages would have nowhere to be absorbed as they did in Earth’s oceans. So, increased amounts of CO2 ould be present in Venus’ atmosphere, which would then compound in more released CO2 that also goes into the atmosphere and further strengthens an already very strong greenhouse gas effect. This compounding effect is known as a runaway greenhouse effect, and it plays a huge part in Venus’ scorching temperatures because the greenhouse effect is so strong that it traps enormous amounts of heat.
The Roche limit
The Roche Limit is a minimum distance in which an orbiting body can get to a planet before the planet’s gravitational tidal forces will break apart the orbiting body. An orbiting body is held together by its own central gravity, and if that body encroaches on the Roche Limit and gets too close to the larger body that it is orbiting, the stronger gravitational force will exceed the orbiting body’s central gravity and cause the body to disperse and disintegrate. The planet has stronger gravitational forces than orbiting objects due to their larger size, and they are strong enough where they can exceed an object’s central gravity and keep it from being able to hold the object together. You will find that objects in the orbital paths of planets, such as moons or the rings of the outer planets, all exist outside of the Roche limit where they are able to maintain thanks to their own gravity without getting affected by the stronger forces of the planet.