Description
Explores exoplanet detection, demographics, orbital architectures, atmospheres, biosignatures, habitable zone models, extremophiles, prebiotic chemistry, and the scientific limits of life detection (the official catalog description). Every physical tool developed in this course — the radial-velocity semi-amplitude equation, the transit depth/duration relations, the mass-radius interior-composition degeneracy, the atmospheric scale-height and Jeans-escape derivations, the radiative-equilibrium habitable-zone boundary, biosignature disequilibrium/false-positive reasoning, and the Drake equation as a structured estimation framework — is derived from first principles and then applied to real, live-verified exoplanet systems (51 Pegasi b, the first planet discovered around a Sun-like star; HD 209458 b, the first transiting exoplanet and the first exoplanet atmosphere ever measured; and the TRAPPIST-1 seven-planet system, reused and extended from this curriculum's ASTR 320 course) plus real, published extremophile and prebiotic-chemistry literature; see reference-log.md for full data provenance.
Learning Outcomes
- Derive the radial-velocity semi-amplitude equation and the transit depth/duration relations from first principles, and apply both to real discovery-era measurements (51 Pegasi b, HD 209458 b).
- Interpret exoplanet demographic data (occurrence rates, the mass-radius relation, the radius valley) with explicit attention to each detection method's selection effects.
- Explain orbital architecture (eccentricity, mean-motion resonance, migration) and the mass-radius interior-composition degeneracy using real system data, including TRAPPIST-1's resonant chain.
- Derive atmospheric scale height and the Jeans escape parameter, and apply both to real transmission-spectroscopy and atmospheric-escape measurements of HD 209458 b.
- Derive the classical, radiative-equilibrium habitable-zone boundary and critically evaluate its necessary-but-not-sufficient relationship to genuine habitability, using climate-feedback and tidal-heating counterexamples.
- Apply biosignature disequilibrium/false-positive reasoning and documented extremophile/prebiotic-chemistry evidence to construct an honest, appropriately hedged scientific assessment of a real exoplanet system's astrobiological plausibility, including a personally justified Drake equation estimate.
Textbook and Materials
Primary reading: OpenStax Astronomy 2e (free, openly licensed; local extracted reference copy under references/openstax-astronomy-2e-extracted.txt and problem index under references/source-indexes/). Exoplanet detection methods are introduced descriptively in the "Exoplanets" section of Chapter 7 (Other Worlds: An Introduction to the Solar System); habitable-zone, biosignature, and Drake-equation topics are introduced descriptively in Chapter 30 (Life in the Universe). These chapter citations follow the ASTR320/330 precedent of native OpenStax chapter numbering, extrapolated by analogy rather than independently cross-checked against embedded figure/table numbering this session — flagged for human spot-check in reference-log.md. Because ASTR 350 is an upper-division elective, nearly every quantitative topic here (the radial-velocity and transit derivations, the mass-radius composition degeneracy, atmospheric scale height and Jeans escape, the radiative-equilibrium habitable-zone boundary, and the Drake equation) goes well beyond OpenStax Astronomy 2e's introductory, descriptive treatment; each lecture's slides and notes state explicitly where this course extends beyond the assigned introductory reading.
Assessment
| Component | Weight |
|---|---|
| Problem sets (7) | 30% |
| Labs (7) | 30% |
| Midterm exam (Lectures 1–7) | 15% |
| Final exam (cumulative, emphasis Lectures 8–14) | 20% |
| Participation and reading checks | 5% |
Lecture, Lab, and Problem-Set Cadence
The course runs 14 lectures, 7 labs, and 7 problem sets — a matched 1:1 biweekly cadence in which each lab and its paired problem set both follow the same two-lecture block, following the ASTR 230/ASTR 310/ASTR 320/ASTR 340 matched-cadence precedent for a standard-format 3-credit, 14-lecture course. This choice was confirmed against the actual lecture content, not assumed from file counts alone: the course is organized into seven thematic units of exactly two lectures each (unlike ASTR 320's variable-length 2-3 lecture units), so a strict two-lecture-per-lab grid is the natural and unambiguous cadence here — every lab and problem set reuses the physical tool(s) derived in its immediately preceding two-lecture unit (e.g., Lab/PS 01 apply Lecture 01's radial-velocity semi-amplitude derivation and Lecture 02's transit depth/duration derivation to the real 51 Pegasi b and HD 209458 b discovery measurements). This is documented explicitly here, rather than left implicit, because the seven-unit thematic structure (Detection I; Detection II and Demographics; Architectures and Interiors; Atmospheres; Habitability; Biosignatures and Life's Limits; Origins and Synthesis) is a deliberate simplification relative to ASTR 320's uneven unit lengths, chosen because this elective's topics divide naturally into balanced two-lecture pairs without the solar-system-specific pacing constraints that produced ASTR 320's variable unit lengths.
| Lab/PS Unit | Lectures | Lab | Problem Set | Topic | Thematic Unit |
|---|---|---|---|---|---|
| 1 | 1–2 | Lab 01 | PS 01 | Radial velocity and transit detection (51 Pegasi b, HD 209458 b) | Unit 1: Detection I |
| 2 | 3–4 | Lab 02 | PS 02 | Complementary detection methods and exoplanet demographics | Unit 2: Detection II and Demographics |
| 3 | 5–6 | Lab 03 | PS 03 | Orbital architectures (TRAPPIST-1 resonances) and interior structure | Unit 3: Architectures and Interiors |
| 4 | 7–8 | Lab 04 | PS 04 | Atmospheric characterization and escape (HD 209458 b) | Unit 4: Atmospheres |
| 5 | 9–10 | Lab 05 | PS 05 | The habitable zone and climate feedback | Unit 5: Habitability |
| 6 | 11–12 | Lab 06 | PS 06 | Biosignature false positives and extremophile limits | Unit 6: Biosignatures and Life's Limits |
| 7 | 13–14 | Lab 07 | PS 07 | Capstone: prebiotic chemistry, the Drake equation, and full synthesis | Unit 7: Origins and Synthesis |
Revision Policy
High standards apply to all graded work. Problem sets and labs may be revised and resubmitted once for improved credit within one week of return, provided the resubmission includes a short change note identifying what was corrected and why (see each problem set's assessment instructions for full criteria).
Prerequisites Check
ASTR 320 (Planetary Science) or ASTR 310 (Stellar Astrophysics) is required as a prerequisite because this course's quantitative toolkit builds directly on tools developed in both: the radiative-equilibrium temperature derivation (ASTR 320 Lecture 08, reused and extended here for the habitable zone in Lecture 09), the hydrostatic atmospheric-structure and Jeans-escape-parameter derivations (ASTR 320 Lectures 07 and 09, extended here to exoplanet atmospheres in Lectures 07-08), and the general first-principles derivation habit and stellar-physics background (ASTR 310) needed to derive the radial-velocity mass function and the mass-luminosity-based habitable-zone scaling used throughout this course. Students who completed ASTR 320 will recognize TRAPPIST-1 as the same live-verified real system used there, now extended with detection-method, atmospheric-escape, and astrobiological analysis beyond ASTR 320's scope; students arriving via ASTR 310 will recognize the tidal-circularization and radiative-equilibrium derivations as directly analogous to stellar-astrophysics tools applied here to planetary and exoplanetary systems.