Intergalactic Planetary
Table of Contents
Solar system Models & the modelling process
This project was about making scientific models, and learning about objects from the incredibly small to the infinitely big. We started by looking at objects that are very big, specifically our solar system. Personally, I'm fascinated with space so I enjoyed learning about the planets and the physics behind them.
We started by creating a model of the solar system based on our basic understanding of the solar system and the orders/names of the planets (Model 1). After our first model, we expanded our understanding of scale and size using data and diagrams and then made a second model to represent this new data. Then we added new data to our model based on other data-tables to further understand the differences and dimensions of our planets (Model 3).
For Model 4, we were given a new planet, which we called Planet X, Using the data of other planets in our solar system, we were able to make a prediction about Planet X's escape velocity, the needed upward velocity to escape the influence of gravity from the planet. Planet X turned out to be the dwarf planet Eris similar to Pluto, which is supported by our data because Pluto's data is very similar to Planet X's data.
Finally, For Model 5, we focused on precisely calculating certain attributes of objects in our solar system. Along with that we were given a new object which we called Planet Y. Using our new equations we precisely calculated certain aspects of our planet's seasons, average temperature, escape velocity and acceleration due to gravity. At this point in the process we had a good understanding of how the objects in the solar system work and how their values relate to each other.
Model #1 (Basic Idea)
Model #2 (Basic representation of data) & Model #3 (Intermediate level data)
Model #4
Model #5
Extra Models
My model on scratch
If the Moon Were Only 1 Pixel - A tediously accurate map of the solar system.
By Josh Worth
Physics concepts
Orbits
All celestial bodies in the solar system orbit in circular or elliptical (oval) paths. These work due to centripetal force, in the form of gravity, tangential velocity and rotational inertia (described before in the alternative energy vehicle project). Technically all planets, excluding dwarf planets, are falling toward the sun, but are also being pushed away from the sun due to their tangential velocity being at a 90° compared to the sun. Because of these opposing forces, the planets never actually fall into the sun.
Rotation (spin) vs Revolution (orbit) (Review from Alt. Energy Vehicle)
Rotation (spin)
A rotation or a spin is when an object does not change position but spins around it's center of rotation. The Earth, for example, makes one rotation, also known as a day, in 24 hours.
Revolution (orbit)
A revolution, or orbit, is when an object moves in a circular path around another object or point in space. The Earth makes one revolution around the sun, in year, or 365.25 days
Tangential Speed (velocity, v, m/s) vs Rotational Speed (ω, rpm) (Review from Alt. Energy Vehicle)
Tangential speed, also known as linear speed, is the movement of an object in a straight line towards a particular direction. Rotational speed is the speed that something rotates and is symbolized with the Greek letter ω. Rotational speed can be measured in rotations per second, degrees per second and mostly commonly RPM, rotations per minute.
If you are standing on a rotating object you are revolving around the center of rotation. The further you get from the center the faster you will be traveling because you will revolve in the same amount of time but you cover more distance. Your rotational speed is the same but you have more linear speed.
Centripetal Force vs. Centrifugal Force (Review from Alt. Energy Vehicle)
Centripetal Force (Gravity)
Centripetal force is the force that pushes a revolving object inward towards the center of rotation (the center of the circular path).
Centrifugal Force (Fake force)
Centrifugal force is the feeling of being pushed outward while revolving in a circular path. Unlike centripetal force, centrifugal force is a fake force and is actually caused by inertia.
Force and speed on strange orbits.
Dwarf planets are VERY strange. They are known for their offset and elliptical orbits. These orbits can vary wildly from the calmer orbits, Example: Ceres, and the EXTREMELY strange, Example: Sedna.
Due to dwarf planets being at disproportionate distances away from the sun at different times, they change in gravitational influence from the sun (Check the Force of Universal Gravitation Equation for a more in depth explanation). Because planets remain at a constant distance from the sun; planets never experience a change in gravity from the object they are orbiting so they do not change speed. Although, dwarf plats are offset and have imbalanced orbits so at some points they are closer to the sun and have a change in the force on them due to gravity. The closer the object is to the center in it's orbit, the faster it moves.
Scientific Notation
Scientific Notation is the way scientists represent numbers that are really big or really small. For example, the number 456000000000000 could be better represented by putting it in scientific notation: 4.56x10^14. Scientific notation complicates equations by adding the extra layer of exponents to each equation where they're used. Scientific notation is great for showing and calculating incredibly large values and incredibly small numbers, which show up very frequently when talking about planets.
Gravity (Fg)
Gravity is in a way the only "real force". Most, if not all, other forces are based around atoms and other stuff in the way. Gravity, however is only based on the mass of the two objects and the distance between the two object's center of mass.
Gravity between two objects never goes away unless the objects are an infinite distance apart. Instead; it the amount of force between the objects decreases the farther the get away from each other. the equation for the force of gravity between two objects in Fg =Gm₁m₂/d². Believe it or not, you are always being dragged toward mars. The reason you don't eventually end up on mars is because the Earth has substantially more mass, and Mars is much farther away.
Gravitational Constant (G)
The gravitational constant is the gravitational attraction, in Newtons, of two objects with 1kg of mass that are 1 meter away from one another. This makes it a key multiplier when calculating the gravitational attraction of different objects. G= 6.67x10^-11 which is scientific notation for the number 0.0000000000667 newtons of force.
Fg =Gm₁m₂/d² and Fg=mag
The equation Fg =Gm₁m₂/d² is the way of calculating the gravitational attraction between two objects. M₁ and m₂ represent the masses of the objects and d is the distance between the object's centers of mass. The previous equation we used to calculate this was Fg=mag. Both of these equations function correctly, but Fg=mag assumes that the object is on Earth, because acceleration due to gravity(ag) is different for every object/planet depending on their mass and distance from their centers of gravity.
Reflection
Because this project wasn't very big; we were paired in groups of two. I was on my own for the first couple of days (Models 1 and 2), so I was working on my own till my group member came back. We both worked hard, maintaining good cooperation and a attitude. Towards the end of the project, I felt like I was starting to fall behind in my leadership and productivity, although I was still happy with the place I was at. Me and my teammate both pulled our weight of the project and worked to understand the concepts presented.