NASA’s Webb may have discovered the ingredients for life in a cold, dark cloud
A few hundred light-years from Earth (which is unusually close, cosmically speaking) lies a mysterious, hazy expanse called the Chamaeleon I molecular cloud. In an already cold and dark universe, this hazy stellar nursery is believed to be the one of the coldest and darkest neighborhoods known to date. And it is often in the darkest corners of space that we find the brightest embers of the evolution and history of our universe.
Writing in the journal Nature on Monday, scientists working with the James Webb Space Telescope reported that pointing this machine at Chamaeleon I revealed an amazing menagerie of icy molecules hidden in the cloud. But these are not just old molecules. These are the kind of interstellar bricks that will one day coalesce into the next generation of stars, planets – and could even lead to the start of life as we know it.
Sure enough, in addition to structural ice chunks such as frozen carbon dioxide, ammonia, and water, the JWST also managed to detect evidence of so-called “prebiotic molecules” in the cloud, according to a press release about the discovery. It simply refers to specific chemicals known to promote the right conditions for the precursors of life.
“Our identification of complex organic molecules, such as methanol and potentially ethanol, also suggests that the many star and planetary systems growing in this particular cloud will inherit molecules in a fairly advanced chemical state,” said Will Rocha. , an astronomer at the Leiden Observatory who helped with the discovery, said in a statement. “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.”
In other words, maybe Earth humans, flowers, and microbes aren’t that special. Perhaps we are not alone in the universe because the ingredients that made us up are extraordinarily common by-products of baby stars growing up in big bad suns.
OK, to be clear, that doesn’t mean we found evidence of extraterrestrial life or anything drastic like that. I mean, we don’t know exactly what will happen to these cloud-borne molecules over time as the mini-solar system look-alikes begin to form.
However, this opens up (very preliminary) leads in the hunt. “These observations open a new window into the formation pathways of the simple and complex molecules that are needed to make the building blocks of life,” said Melissa McClure, astronomer at Leiden Observatory and lead author of the paper. in a press release.
Follow a chameleon cloud
In a nutshell, the JWST works by using its gold-plated mirrors and high-tech instruments to detect specific wavelengths of light that fall into the infrared region of the electromagnetic spectrum.
Infrared light is very different from the ordinary light we are used to seeing with the naked eye. Unlike the latter, known as visible light, infrared wavelengths are essentially invisible ours. Yet a great deal of light emanating from different regions of the universe – especially from inside star-forming clouds – arrives at our vantage point on Earth as invisible infrared light.
This is why the JWST is so important.
This machine is literally built to decode all that infrared light from deep space and turn it into something understandable to our minds and technology – elucidating a host of cosmic secrets otherwise shielded from our sight.
And, you guessed it, as the JWST observed Chamaeleon I, it picked up a bunch of infrared wavelengths associated with the icy molecules hidden inside the haze, and turned them into information digestible by the team of scientists who operate the scope.
Basically, the light emitted by a star in the background of the cloud somehow touched everything in its path on the way to the JWST lenses, located a million miles from our planet. Specifically, when the wavelengths passed through the cloud itself, they came into contact with all those icy molecules floating inside.
So some of the starlight was absorbed by these icy molecules, leaving a kind of fingerprint in its wake. These fingerprints are called absorption lines – and once analyzed they can help infer whatever created them. In this case, the fingerprints led scientists to learn more about ice molecules.
“We simply couldn’t have observed this ice without Webb,” said Klaus Pontoppidan, Webb project scientist at the Space Telescope Science Institute, who participated in this research, in a statement. “In regions this cold and dense, much of the light from the background star is blocked, and Webb’s exquisite sensitivity was needed to detect starlight and thus identify ices in the molecular cloud. “
Going forward, the team intends to see how these ices and prebiotic components evolve over time in Chamaeleon I as planet-forming disks begin to appear in the region. As McClure explained, “this will tell us what mixture of ices – and therefore what elements – may possibly be delivered to the surface of terrestrial exoplanets or incorporated into the atmospheres of gaseous or ice giant planets.”
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