Learning Objectives
- Translate science questions into measurement payload requirements.
- Balance science return, technical risk, planetary protection, operations complexity, and flight time.
- Test whether a mission recommendation is robust to alternate stakeholder weights.
Preparation
Review Lectures 11-14 on small bodies, exoplanet context, habitability, planetary protection, and mission design. Bring notes from one previous ASTR 120 lab that could motivate a science question.
Materials and Data
../data/lab-07-mission-trade-matrix.csv, an instructor-created trade table with named mission precedents and NASA source pages.- Spreadsheet for weighted scoring and sensitivity tests.
- Course lab results from at least one earlier activity to use as science rationale.
Apparatus and Setup
- Open the CSV and add columns for normalized benefit, normalized cost/risk, baseline weighted score, and alternate weighted score.
- Use baseline weights: science return 40%, technical risk 20%, planetary protection 15%, operations complexity 15%, flight time 10%.
- For risk, protection, complexity, and flight time, invert the score so lower burden increases the total: converted score = 6 - listed score for 1-to-5 columns; for flight time, rank concepts from 5 for shortest to 1 for longest.
Procedure
- For each concept, identify the primary science question and the payload measurement that directly tests it.
- Calculate a baseline weighted score using the setup weights.
- Create an alternate stakeholder scenario: astrobiology-first, low-cost-first, or planetary-protection-first. Define the new weights before seeing the result.
- Recalculate scores and record whether the preferred mission changes.
- Choose one mission and write a traceability chain: science question -> measurement -> instrument -> target -> risk or uncertainty.
Measurement Record
| Mission concept | Baseline score | Alternate score | Key measurement | Dominant uncertainty or risk |
|---|---|---|---|---|
| Venus cloud microprobe | ||||
| Europa plume flythrough | ||||
| Enceladus plume sample return concept | ||||
| Mars polar ice drill scout | ||||
| Trojan asteroid flyby |
Analysis and Uncertainty
Treat all 1-to-5 ratings as uncertain by +/-1 unless the precedent mission already demonstrated the relevant capability. Run a one-at-a-time sensitivity test for the winning concept: lower its science score by 1, raise its dominant risk by 1, and lengthen flight time by one rank. Report whether it still wins. Discuss any ethical or planetary-protection consequence that a numerical score hides.
Deliverables
- Completed decision matrix with baseline and alternate stakeholder weights.
- One ranked chart of mission scores with the winning concept highlighted.
- One-page mission recommendation with traceability chain and sensitivity result.
- Provenance note citing NASA mission/program pages and
lab-07-mission-trade-matrix.csv.
Assessment Criteria
- Decision matrix calculations and inverted risk scoring are correct: 30%.
- Science traceability connects question, measurement, instrument, and target: 25%.
- Sensitivity analysis tests real uncertainty rather than just restating preference: 20%.
- Planetary-protection or ethical constraint is addressed concretely: 15%.
- Complete provenance note: 10%.
References, Software, and Data Provenance
Data file: materials/ASTR120/data/lab-07-mission-trade-matrix.csv. Sources: NASA Venus exploration, Europa Clipper, Cassini Enceladus, Mars exploration, and Lucy mission pages. Processing state: instructor-created decision-matrix dataset using public mission precedents and pedagogical risk scores; scores are not official NASA cost or review ratings.