JWST’s unparalleled ability to observe the shrouded hearts of distant clouds has revealed the elements of biochemistry in the coldest, darkest places we’ve seen so far.
In a molecular cloud called Chamaeleon I, located more than 500 light-years from Earth, data from the telescope have revealed the presence of frozen carbon, hydrogen, oxygen, nitrogen and sulfur, vital elements for the formation of atmospheres and molecules such as amino acids, collectively known as CHONS.
“These elements are important components of prebiotic molecules such as simple amino acids, and therefore the ingredients of life, if you will.” says astronomer Maria Drozdovskaya from the University of Bern in Germany.
In addition, an international team of researchers led by astronomer Melissa McClure of Leiden University in the Netherlands has also identified frozen forms of more complex molecules, including water, methane, ammonia, carbonyl sulfide, and the organic molecule methanol.
The cold, dense clusters in molecular clouds are where stars and their planets are born. Scientists believe that CHONS and other molecules were present in the molecular cloud that gave birth to the Sun, some of which were later delivered to Earth via an icy comet and asteroid impacts
Although the elements and molecules detected on Chamaeleon I are quietly floating around right now, they could one day be caught up in planet formation, delivering the necessary ingredients for the emergence of life on new baby planets.
“Our identification of complex organic molecules, such as methanol and potentially ethanol, also suggests that many star and planetary systems developing in this particular cloud will inherit molecules in a fairly advanced chemical state.” explains astronomer Will Rocha from the Leiden Observatory.
“This could mean that the presence of prebiotic molecules in planetary systems is a common result of star formation rather than a unique feature of our own Solar System.”
Chamaeleon I is cold and dense, a dark conglomeration of dust and ice that is one of the closest active star-forming regions to Earth. A census of their composition, therefore, can tell us a great deal about the ingredients involved in the formation of stars and planets and contribute to an understanding of how these ingredients are incorporated into newly formed worlds.
JWST, with its powerful infrared sensing capabilities, can see through dense dust with more clarity and detail than any previous telescope. This is because infrared wavelengths of light don’t scatter dust particles the way shorter wavelengths do, meaning instruments like the JWST can see through dust better than optical instruments like the JWST. the hubble.
To determine the chemical composition of the dust in Chamaeleon I, scientists rely on absorption signatures. Starlight traveling through the cloud can be absorbed by elements and molecules in it. Different chemicals absorb different wavelengths. When a spectrum of the emerging light is collected, these absorbed wavelengths are darker. Scientists can then analyze these absorption lines to determine which elements are present.
JWST looked deeper into Chamaeleon I for a census of its composition that we have never seen before. He found grains of silicate dust, the aforementioned CHONS and other molecules, and ice colder than any previously measured in space, at around -263 degrees Celsius (-441 degrees Fahrenheit).
And they found that, for the cloud density, the amount of CHONS was less than expected, including only about 1 percent of the expected sulfur. This suggests that the rest of the materials may be locked up in places that cannot be measured, for example, within rocks and other minerals.
Without more information, it is difficult to assess at this point, so the team intends to obtain more information. They hope to get more observations that will help them map the evolution of these ices, from covering the dust grains of a molecular cloud to their incorporation into comets and perhaps even the seeding of planets.
“This is just the first in a series of spectral snapshots we will take to see how ices evolve from their initial synthesis to the comet-forming regions of protoplanetary disks.” McClure says.
“This will tell us what mix of ices, and therefore what elements, may eventually be delivered to the surfaces of terrestrial exoplanets or incorporated into the atmospheres of gas or ice giant planets.”
The research has been published in nature astronomy.
And you can download wallpaper-sized versions of JWST image of Chamaeleon I here.
