Aha Thesis Throughout this trimester, we have completed several activities to help us answer our driving question of, “which Planets would be the most habitable and how can we determine this. ” In order to organize our process of learning and how we can find these planets, we divided the question into three learning units. Our units included Nuclear Reactions and Star, Waves and light, Analyzing stars, and Circular motion and orbits. Our first unit was Nuclear Reactions and Stars.
This unit was focused on teaching us the properties of nuclear reactions, where they occur, and how they help us find tars, relating directly to our driving unit. The main idea of this unit was that there are three types of nuclear reactions. Radioactive decay is the release of either an electron, a helium atom, or energy, in an unstable and large elements. Fission is the process of when a neutron traveling at fast speeds strikes a large element, causing it to split into two elements and the release of usually around three neutrons. Finally, fusion occurs when two elements fuse together, producing a large amount of energy.
This process requires extreme heat, like that of stars, in order to create an environment where all molecules move around at fast speeds, making them susceptible to fusion. Therefore, stars produce extreme amounts of energy through fusion. The heat produced by the sun makes fusion happen all the time. Next, through learning the equation E=mica, we realized that even a small amount of mass loss, which occurs in fusion, produces a large amount of energy. To sum up this unit, we learned about the evolutionary paths of stars and how they are affected by their mass.
Basically, average mass stars go through a simple path of stellar nebula, protestor, average star, red giant, white dwarf. However, high mass stars go through a stellar nebula, high mass star, super red giant, supernova, then either a neutron star or black hole. It becomes a black hole only of its mass is incredibly high. In order to understand why this happens, we watched an understanding stars video and did some helpful bookwork. Stars go through this cycle as the balance between gravity and the stars outward force (usually fusion) changes.
As a star gets hot enough to start fusion and create a variety of new elements, it’s outward force increases, causing the star to expand. As star then begins to run out of fuel, the star begins to use larger elements, cooling the gas and causing it to spread outwards. Finally, as the star begins to lose all of its elements to fuse, gravity breaks the gravitational equilibrium it once had and collapses the star. Through this unit, we learned how stars work and how nuclear reactions are what cause the release of energy in nature. Our second unit consisted of waves and light.
Now that we knew how stars work, we had to learn how we know so much about stars, how we find them, and how we find planets that orbit them. In order to accomplish this, we first investigated waves. Eaves: transverse (electromagnetic) and longitudinal waves (sound). Then we learned that there are two speed equations for waves. One is the obvious s=d/t. The other equation, which is Just a derivative of this, is speed-?wavelength * frequency. Through this, we could calculate the wavelength or frequency of any electromagnetic wave if we knew one or the other (because the speed is always a constant).
Next we learned about the electromagnetic spectrum. This is basically a list of electromagnetic waves from least energy (longest wavelength) to most energy (shortest wavelength). This allowed us to see how much we can not see and the frequencies of these waves. Furthermore, we learned the importance of intensity, in my opinion, the most important part of this unit. Intensity is defined as the amount of energy in a given area. Basically, as we move away from the source, the area the source occupies increases, thus decreasing the energy we feel or see.
Through the intensity lab, in which I did high tech, we figured that the relationship is an inverse square. Using our now known knowledge about intensity, waves, and luminosity(power output or dotage), we could now use the luminosity of the star to find the habitable zone. To do this, we used the equations given by the online activity, eventually allowing us to see if there was a habitable planet, usually fictional, in the stars zone. In unit three, we expanded on our star knowledge from unit one and two. One of the main projects we did in this unit was the star evaluation sheet.
We had to find a random star using the online planetarium given to us and then research it’s characteristics. Once we found a star we liked, we used websites, such as wisped, o find out the basics of the star. Through the website, we were able to find distance from the earth, Surface temperature, the star’s radius, the star’s mass, and its Luminosity. Using this information, we were able to use our past knowledge and equations and new equations (wavelength of peak emission=b/T where b is Wine’s displacement constant) in order to further our information about the star.
Next, we used the equation of r=((1360*Lasts/Lulus)/ in order to find the outer and inner edge of the stars habitable zone (using 720 and 1500 as established intensities for habitable zone edges). Then using what we knew about that mass, luminosity, and temperature of the star, we could use the H-R diagrams, which we learned about this unit doing book work, to determine the stage the star was in. Sadly, my star was a massive star in its superstring stage.
Even though the star did have a useable habitable zone, the star’s life span was way too short, leading to the conclusion that my star shouldn’t be considered as a possibility for Project Cygnus colony ship. Furthermore, we also did an activity online in which we chose a star offered, figured out whether it had a planet orbiting it through the brightness dips in the graph), figured out the period of the planet (again through the amount of time it took for the brightness dips to occur), and then through a series of equations, we found the habitable zone and saw whether the planet was inside of the zone.
This unit helped expand our knowledge on stars and to figure out how to find the habitable zones of stars and whether a planet is orbiting in that zone. Objects are able to travel in a circle and why two objects in orbit do not collide into each other. Through a series of readings and activities, such as the water demo, we earned that centripetal force is the force holding an object in circular motion and it points radically inward. However, this brought up a couple of questions. These included: “Why does the water in the cup during the water demo not fall out? ND Why do we not fall out of a reallocates when we are upside down. In order to answer both, we first looked at properties of an object traveling in a circular direction. First, we learned that centripetal equation is basically acceleration in a circular direction that points inward. In a object is traveling in a circular path, we can SE the equation centripetal acceleration=(tangential speed)AY / the radius of the circle in meters. To find the tangential speed, the equation we used was speed-?circumference of the circle/the period of the object.
This is basically speed-?distance/time. These equations helped us do our buggy lab in which we found the centripetal acceleration and used this to help us find the amount of centripetal force (in Newton’s) by using the equation f=mass*acceleration. The mass was easily found via a scale and we used the equations given to help us find the acceleration. However, this still didn’t totally answer the question of why we do not all out of a roller coaster when we are upside down.
Through a presentation and a roller coaster Journal glasswork, we realized that the reason this happens is because there is a normal force caused by our speed and inertia that causes us to resist falling. Through all of this, I realized that this perfectly explained the driving question of this unit, which stated Why does the moon not crash into the planet it is orbiting, the earth? As a result of these activities, I understood that this is because the object is constantly accelerating towards the center, causing an elliptical like orbit where he planet never crashes.
In conclusion, this unit taught me why objects stay in orbit and the forces involved in circular motion. With still more to go in this unit, I am quite excited to see where this leads us. Overall, all of the activities we have done have lead us closer to answering our driving question of the unit, “What planets are habitable and how can we determine this. ” Through a series of activities, labs, and lectures, we have learned about the properties of stars and their orbiting planets, all of which have helped us determine information about stars and their orbiting planets.