Cumulative: Lectures 01, 04, 05, 09, 13, 14 ยท Student-facing assignment
Show reasoning, units, diagrams or plots where useful, and source acknowledgments. Numerical answers without explanation receive limited credit. Eligible submissions may be revised after feedback.
A headline says: 'Earth-like planet found.' List four different meanings this phrase could have. For each, name the measurement needed to support it, such as radius, mass, density, orbit, atmosphere, or biosignature evidence.
Choose one claim from the course: a star is a giant, a galaxy contains dark matter, or the universe is expanding. Build an evidence chain with at least four links from observation to model conclusion. Identify the weakest link.
A claim says a galaxy 100 Mpc away changes position on the sky by 1 degree in one year because it is moving sideways. Explain why this is implausible using angular motion and distance. A qualitative order-of-magnitude argument is sufficient.
Pick one equation from the course and explain what it lets astronomers infer that cannot be measured directly. Include one limitation of the equation.