# Assessment Instructions: Problem Set 04 — Atmospheric Structure, Radiative Balance, and the Greenhouse Effect

## Inputs to Inspect
Student submission, this problem set, the solution key, the corresponding lecture slides/notes, and the shared
constants in `materials/ASTR320/src/generate_astr320_content.py` where a problem reuses course data.

## Grading Standard
Award credit for correct method and units first, then for the specific numeric result. A student who shows correct
reasoning with a small arithmetic slip should receive most of the available credit; a student with a correct-looking
number but no visible derivation steps should not. Because this is a 300-level quantitative course, full marks require
a genuine derivation (not just formula substitution) wherever the problem set asks for one.

## Problem-Level Criteria
- Problem 1: must connect escape velocity AND temperature to Jeans escape, not just assert Mercury has no atmosphere.
- Problem 2: must state the pressure-ratio order of magnitude AND correctly conclude mass/opacity (not composition) controls greenhouse magnitude.
- Problem 3: must show the linear T-scaling explicitly, not just state a new H value.
- Problem 4: must use the (1-A)^(1/4) proportional scaling correctly (a common error is treating T_eq as scaling linearly with (1-A)).
- Problem 5: must explain why differential escape is favored over the "born deuterium-rich" alternative, not just describe the escape mechanism alone.

## Resubmission Policy
Students may resubmit within one week of receiving feedback. A resubmission must show a corrected derivation, not
only a corrected final number, and should reference the specific feedback comment it addresses. Regrade to a maximum
of 90% of the original point value unless the error was a grading mistake.

## Common Errors to Flag
- Treating T_eq as proportional to (1-A) rather than (1-A) to the one-fourth power (Problem 4).
- Confusing scale-height's linear dependence on temperature with the equilibrium-temperature formula's quarter-power dependence on flux (Problems 3 vs. 4).
- Describing Venus's and Mars's CO2 atmospheres as fundamentally different in composition rather than in total mass/opacity (Problem 2).