The James Webb Space Telescope (JWST) hasn’t been up in space for very long, and yet already it is taking unprecedented images in high-resolution. Its infrared vision allows us to “cut through the cosmic dust” to see some of the earliest structures in the universe in far more detail than the Hubble Space Telescope – and the results are spectacular!
Opacity is a measure of how easily photons of light pass through a material, while opacity models are the tools scientists use to determine how light interacts with that material as a function of the material’s properties. Different elements and compounds present in an atmosphere surrounding a planet have different spectral “fingerprints.” Meaning, the way these elements and compounds absorb and reflect light can be measured and interpreted to determine whether planets may harbor any signs of potential life.
However, an MIT study has found that these models need improvement in order to produce accurate planetary predictions. Imagine the JWST captures light from a newly-discovered planet. Now imagine there can be three possible planets that current opacity models produce as a result of that light: one is interpreted with an atmosphere of methane (CH4), one with water vapor, and one with a mix, including carbon dioxide (CO2). Which planet is it?? That has big implications for possibilities of life.
“There is a scientifically significant difference between a compound like water being present at 5 percent versus 25 percent, which current models cannot differentiate,” says study co-leader Julien de Wit, assistant professor in MIT’s Department of Earth, Atmospheric and Planetary Sciences. In light of this unprecedented high-resolution data is a chance now for scientists to improve their models, with a combination of lab measurements and theoretical calculations. JWST is not only providing us with imagery of stunning clarity, but also opening up opportunities to refine our knowledge of the universe.