https://www.nasa.gov/image-feature/goddard/2022/nasa-s-webb-reveals-steamy-atmosphere-of-distant-planet-in-detail

I freely admit that my mind is blown any time anyone presents any data that shows anything definite about the atmospheres of exoplanets. I (wrongly) predicted that we would not see this in my lifetime, and I could not be more delighted to be wrong.

The first JWST exoplanet spectrum came in the original release of five images, and identified water in the atmosphere of WASP-96 b. This is a hot gas giant orbiting a Sun-like star more than 1,000 ly away. The spectrum is a transmission spectrum: the planet was observed as it transited the star, and then the spectrum was compared to that of the star when the planet is not in view. The spectrum has a wide range of wavelengths, and multiple water lines are present across the full spectrum. I see other narrower lines there as well that I’m certain are being investigated further.

But already, we have more! In August, a similar transmission spectrum for WASP-39 b was released, (https://www.nasa.gov/feature/goddard/2022/nasa-s-webb-detects-carbon-dioxide-in-exoplanet-atmosphere) showing a clear detection of carbon dioxide in the atmosphere of that hot gas giant.

All that said, it’s a bit of a heavy lift to help students understand how exciting a graph can be!  They’ll need you to help them understand why they should be astonished that we can determine the composition of the atmosphere of a planet (even a Jupiter-sized one) from 1,000 light years away.

Supporting material in the texts and online: This image ties in to a deep fascination about life in the universe---if we are all honest about it, we are anxiously awaiting the first detection of O₂. You might reference this image in the chapters on the Formation of Stars and Planets, the Giant Planets, Exoplanets or Life in the Universe.

Exploration: Exploring Exoplanets

Process of Science Assignment: Light and Spectroscopy

Interactive Simulations: Planetary Orbits Simulator and Habitable Zone

Astrotours: Atmospheres: Formation and Escape

Astronomy in Action videos: Emission and Absorption

Learning Astronomy by Doing Astronomy Workbook, Activity 6: Extraterrestrial Tourism explores the relationship between observations and properties of planets; Activity 35: Finding Habitable Worlds beyond Earth will help students understand why we are interested in the orbital properties of planets.