Astronomical bodies are extremely complicated, containing a variety of physical processes across vast length and time scales. However, it is surprisingly easy to quickly obtain approximate answers to many interesting questions. This is the mindset of order of magnitude astrophysics - where cows are spheres and pi equals three. The goal of this semilab is to learn to think like an astrophysicist.
We will first cover the fundamentals of order of magnitude estimation and formal dimensional analysis. We will ask questions such as: Can you solve a physics problem without knowing any physics? Suppose you are starting a new landscaping business, how many sheep do you need to perpetually mow a lawn? Then we will apply our new skills to several topics and questions. We will begin with a tour of stars. What goes on inside stars and how long do they live? How do stars that get too close to supermassive black holes in the centers of galaxies get torn apart by tidal forces? Then we will explore the physics of planets. What might be the temperature and climate of exoplanets around other stars? What can we learn from observations of exoplanets with modern telescopes? We will end our journey with exotic, compact objects. How do basic quantum mechanical principles determine the mass and radius of white dwarfs and neutron stars? What role do ultra-strong magnetic fields play in their evolution?
Prerequisites: Math requirements are trigonometry and single variable calculus. Physics requirements are mechanics and the basics of electricity and magnetism.