Oceanography ›  Unit 2

Unit 2 Origins of Life & a Habitable Ocean

Earth wasn't always breathable. This short unit traces how the ocean built our atmosphere \u2014 then asks you to use that same standard to judge whether a planet 124 light-years away deserves to be called habitable.

📅 Week 3🏷️ 3 Activities🏷️ 1 Project🏷️ 1 Problem
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The Path Through Unit 2

124 light-years away, a planet called K2-18b might have a liquid ocean. Before anyone gets to call it habitable, someone has to check the evidence. Read the full dossier →
Activity — builds the skill
Project — applies it, target known
Problem — open-ended dossier review (do last)
AActivity3 days total
2-1-1Early Earth's Atmosphere — Before There Was Oxygen
1 day→
2-1-2Photosynthesis & the Great Oxidation Event
1 day→
2-1-3Is the Ocean the Cradle of Life? Reading the Evidence
1 day→
PProject🕑 2 class days

2-1-4  Map the Atmosphere

Build an illustrated timeline tracing Earth's atmosphere from anoxic to oxygenated — every stage driven by something happening in the ocean, not on land.

Turn in: Illustrated atmosphere timeline (infographic or short video) with a caption explaining each stageOpen →
BProblem🕑 2 class days

2-2-1  Could K2-18b Support Life?

Astronomers think a distant exoplanet might have a liquid ocean. Using everything you know about how Earth's ocean became habitable, you assess the evidence and decide what's actually been confirmed — and what's still just a hope.

Turn in: Habitability assessment memo ranking the evidence for each criterion, with a final verdict and a list of what data is still missingOpen →