NIRSpec

And recently, the huge step in this field of science right now is the James Webb Space Telescope.

Operating primarily in the infrared spectrum from 0.6 all the way out to 28 microns, JWST uses an elite suite of instruments like NIRSpec and MERI to read chemical fingerprints that were completely invisible to older space telescopes.

So what chemical fingerprints are astronomers actually hunting for? They aren't just looking for a single isolated gas.

What they really want to find is thermodynamic disequilibrium.

As an exoplanet passes its mother star, James Webb not only measures the drop in brightness, but also how the spectrum of light changes.

The telescope's near-infrared spectrometer, or NIRSpec for short, measures the wavelengths of infrared radiation closest to the visible spectrum.

Molecular bonds absorb energy in this range, and different bonds, like this carbon-hydrogen bond in methane, or this carbon-oxygen double bond in carbon dioxide, absorb different wavelengths.

It means that by measuring which wavelengths are absorbed as a planet transits its star, we can first of all work out if there is an atmosphere, and then, if so, determine which gasses are present.

Oh, I see.

The thermal drift of the NIRSpec detector inside JWST does not care at all about the eight point four six day orbit of LP eight ninety-nine Zingc.

It just warms up whenever it warms up.

Exactly.