JWST’s unique ability to peer into the veiled hearts of distant clouds has revealed elements of biochemistry in the coldest and darkest place we’ve ever seen.
In a molecular cloud called Chamaeleon I, 500 light-years away from Earth, data from the telescope revealed frozen carbon, hydrogen, oxygen, nitrogen and sulfur – elements vital to the formation of atmospheres and molecules such as amines. acids collectively known as CHONS.
“These elements are essential components of prebiotic molecules such as simple amino acids and are thus the ingredients of life.” says astronomer Maria Drozdovskaya University of Bern, Germany.
In addition, an international team of researchers led by astronomer Melissa McClure of Leiden University in the Netherlands also identified frozen forms of more complex molecules such as water, methane, ammonia, carbonyl sulfide and the organic molecule methanol.

The cold, dense clumps in molecular clouds are where stars and their planets are born. Scientists believe that CHONS and other molecules available in the molecular cloud Some of the ones that gave birth to the Sun were later delivered to Earth by an icy comet and asteroid effects
Although the elements and molecules discovered in Chamaeleon I are floating around quietly for now, they could one day be caught up in the process of planet formation, delivering the ingredients necessary for life to new baby planets.
“The identification of complex organic molecules such as methanol and potentially ethanol also suggests that many stellar and planetary systems that developed in this particular cloud would have inherited the molecules in a fairly advanced chemical state.” explains astronomer Will Rocha Leiden Observatory.
“This may mean that the presence of prebiotic molecules in planetary systems is not a unique feature of our solar system, but a common consequence of star formation.”
Xamaeleon I is a cold and dense, dark conglomerate of dust and ice that forms one of the closest active star-forming regions to Earth. Therefore, taking a census of its composition can tell us a lot about the ingredients that go into the formation of stars and planets, and help us understand how these ingredients get into nascent worlds.
With its powerful infrared detection capabilities, JWST can see dense dust with greater clarity and detail than any telescope previously available. This is because infrared wavelengths of light do not scatter dust particles as much as shorter wavelengths, meaning that instruments like JWST can effectively see dust better than optical instruments like Hubble.

Scientists rely on absorption signatures to determine the chemical composition of the dust in Chamaeleon I. Starlight passing through a cloud can be absorbed by the elements and molecules there. Different chemicals absorb different wavelengths. When a spectrum of the resulting light is collected, these absorbed wavelengths become darker. Scientists can then analyze these absorption lines to determine which elements are present.
JWST looked deeper into Chamaeleon I than we’ve seen before to catalog its composition. At about -263 degrees Celsius (-441 degrees Fahrenheit), it found silicate dust grains, CHONS and other molecules mentioned above, and ice colder than previously measured in space.
And they found that the amount of CHONS for the cloud density was lower than expected, including only 1 percent of the expected sulfur. This suggests that the remaining materials may be locked up in places that cannot be measured – for example, inside rocks and other minerals.
Without more data, it’s hard to measure at this point, so more data is what the team is aiming for. They hope to obtain more observations that will help them map the evolution of these ices, from covering the dust grains of the molecular cloud to being incorporated into comets and possibly seeding planets.
“This is the first of a series of spectral images we will obtain to see how protoplanetary disks evolved from the initial synthesis of ices into comet-forming regions.” McClure says.
“This will tell us what kind of ice mix – and therefore what elements – could be delivered to the surfaces of terrestrial exoplanets, or introduced into the atmospheres of giant gas or ice planets.”
The study was published Natural Astronomy.
And you can download wallpaper-sized versions JWST’s image of Chamaeleon I is here.