Active Galactic Nuclei
Topic/Concept: Active Galactic Nuclei
Type of Activity: discussion + group work + discussion
Prerequisite knowledge required: galaxy structure, gravity, radiation, emission lines, doppler shift
Resources required: chalkboard
Learning Objectives: describe an AGN, illustrate how a single object can look very different when viewed from different angles
Common misconceptions:
Detailed description of activity: have 6-8 students approach the chalkboard and agree to be artists while the rest of the students are instructed to draw on their papers. have the students draw the AGN unified model as you describe it. first, a black hole, then an accretion disk, dusty molecular torus, jets. i also have them label the size scales of each component in light minutes/days/years. then i have the students sit down and we discuss the different kinds of AGN : seyfert I and seyfert II, radio galaxies, blazars and their characteristics and list them on the board. i talk about how we think that these are all the same object just seen at different angles. then, using the best student picture on the board, i label four viewing angles with arrows and ask the students to (in groups) match the four kinds of AGN with the four viewing angles. then we talk about how each viewing angle can produce different observational results. if there’s time we talk about the number distribution of agn with redshift and have the students brainstorm why these object turn on and off.
Assessment: this is mostly done through interacting with the students as they work in groups. you could also have them write up what they learned at the end of class and collect and look over it.
Associated files and images:
Comments: it would be cool to show a 3D rotating AGN model to help the students visualize.