Bell ringer: start here (while attendance happens)
Prior-knowledge probe · 5 min

From last block: name one thing a transit observation can tell us and one thing it can't.
Task: Pair-share, 60 seconds.

Answer in your Field Notebook, dated.

Today we are learning

I can extract key habitability data from a card, justify why I chose this exoplanet, and identify two questions I'll need to answer about my chosen planet in Blocks 7–8.

I can: tick as you go (for you, not for marks)
full course map →
AI Partners available for today's work
Remember: every AI use gets documented. → AI Documentation Template

What today is about

Choice-lock day. Eight candidates. One verdict to defend.

You've been hearing about the eight candidate exoplanets since Block 4. Today you read all eight data cards and lock your choice for the Goldilocks Report. The work between now and Block 10 is built around the planet you pick today: your framework, your sources, your verdict, your defense.

Not all eight are equally useful for your framework workout. TRAPPIST-1 e has the richest dataset and the most JWST work, but JWST's recent atmospheric non-detections on its siblings have complicated the "most habitable" framing. K2-18 b is the fastest-moving science target on the list: its dimethyl sulfide detection in 2023 is genuinely contested. Gliese 581 d is the pedagogical plant: its very existence is disputed (the 2007 detection may be stellar activity artifact). Kepler-186 f and Kepler-452 b are media darlings with thin primary-source support, useful for OPVL practice but harder to defend a verdict on. Pick the planet that gives you the best framework workout, not the most famous name.

The Planet Hunter has been in your toolkit since Block 3: today it becomes your main advisor for choice-lock. It still refuses verdicts: the lock is your call.

Before you start the work

Keep these open. The candidate table below is the data you choose from, and these cards are how you read it. Notes go in your Class Notebook as a Power outline.

Taking notes? Power 1 seeds for today
the eight candidates · choosing for the workout · the format
Placeholder
Watch (5 min)
TBD: a 2-planet comparison video (e.g. TRAPPIST-1 e vs. K2-18 b) showing how the same "habitable zone" claim has very different evidence behind it for different planets.
Read
Goldilocks Report: Step 1 of the handout lists the 8 candidates and links each to a printed data card. Bring the printed Exoplanet Data Cards handout; you'll annotate it during today's work.
Interact
The Planet Hunter: read the opening message and example exchange before your first conversation if you haven't yet. Bring a specific exoplanet to talk through.
CandidateDistance (ly)What's interesting about it
TRAPPIST-1 e~40Earth-sized, in HZ. JWST has not detected atmospheres on its siblings; this complicates the "most habitable" framing.
Proxima Centauri b4.24Closest known exoplanet. M-dwarf flares are a major atmospheric retention concern.
K2-18 b~124Hubble + JWST detected atmospheric water vapor; possible hycean world. DMS detection (2023) is contested.
Kepler-186 f~580First Earth-sized planet confirmed in a HZ. Too far for direct atmospheric study; OPVL is essential.
Kepler-452 b~1,800"Earth's older cousin" in pop-sci. Larger than Earth (1.6 R⊕); possibly super-Earth or mini-Neptune.
LHS 1140 b~40Rocky, in HZ around a quiet M-dwarf. Excellent JWST target. Less media coverage = harder OPVL practice.
TOI 700 d~101TESS discovery. Earth-sized in HZ. Recent enough that scientific consensus is still forming.
Gliese 581 d~20Genuinely contested existence: 2014 re-analysis suggests stellar activity artifact. Excellent for Limitations practice.

Today's work: choose one path

Three real paths, same destination: a locked exoplanet choice + a profile to defend.

Learning Intention: I can extract key habitability data from a card, justify why I chose this exoplanet, and identify two questions I'll need to answer about my chosen planet in Blocks 7–8.
A
Solo profile build
Pick your exoplanet from the table above. Fill in a one-page profile using the printed data card: distance, host star type, mass, radius, orbital period, atmospheric data status (observed / unknown), HZ status, one major uncertainty. End the page with one sentence: "I chose this planet because…"
Independent · Solo
B
Pair-debate Earth-like vs. Mars-like
With a partner who picked a different planet, debate: is your planet more Earth-like (atmosphere, water possibility, magnetic protection) or more Mars-like (lost atmosphere, frozen surface, no magnetic field)? Defend with at least three pieces of evidence from your data card. Then switch.
Verbal · Pair
C
AI-coached exoplanet interrogation
Use the Planet Hunter to work through one specific uncertainty about your planet ("what does JWST not yet know about K2-18 b's atmosphere?" / "how confident is the Gliese 581 d detection?"). The Planet Hunter will push back; let it. Load the same planet in the Habitability Zone Calculator as you talk; notice how Atmosphere = Unknown propagates as UNCERTAIN through the framework. Document the exchange in the AI Documentation Template.
Conversational · Solo

Open your Class Notebook and type today's entry header as Heading 2:

A: Sep 18 | U1 B6 | Reading Exoplanet Data Cards: Choosing Your PlanetB: Sep 17 | U1 B6 | Reading Exoplanet Data Cards: Choosing Your Planet

What you're submitting today

Locked choice + profile. This is the artifact that drives every subsequent block in the unit.

Exoplanet choice + profile (submit by end of class)

Your one-page exoplanet profile (filled-in data card) PLUS locked-choice declaration: the planet you'll defend in the Goldilocks Report. Include two specific questions you'll answer in Blocks 7 and 8 about this planet.

Submit via Google Classroom (link posted in August)

Rubric link: Ms. Jayanthi/Mr. Ignash uses today's submission to redirect duplicate choices: if everyone picked TRAPPIST-1 e, the Stakeholder Q&A in Block 10 would be repetitive. Variety makes the panel work. Submission feeds the T/T strand of the Goldilocks Report rubric.

One question before you leave

Three to five minutes. Your answer is saved to your reflection journal, where you can read back everything you have written this year.

Stake a position. We'll come back to your "biggest unknown" in Block 8.

Today's reflection is in Google Classroom, under Reflection Journal.

Link posted in August

Sign in with your school account. Your teacher can see what you write here.