Tuesday, June 27, 2023

The James Webb Space Telescope found a molecular building block of life hiding in the Orion Nebula


Natalie Musumeci, Morgan McFall-Johnsen
Tue, June 27, 2023 

Images from the James Webb Space Telescope show a part of the Orion Nebula where methyl cation was detected in a young star system, shown in the lower right segment.
ESA/Webb, NASA, CSA, M. Zamani (ESA/Webb), and the PDRs4All ERS Team

The James Webb Space Telescope detected a key carbon molecule in space for the first time ever.


The methyl cation, or CH3+, molecule was found in a young star system in the Orion Nebula.


The discovery reveals the chemical processes that could give rise to alien life.

NASA's James Webb Space Telescope has detected a key carbon molecule in space for the first time: methyl cation (pronounced cat-eye-on).

The methyl cation, or CH3+, molecule can promote chemical reactions that form more complex carbon molecules — crucial building blocks for life.

Scientists have theorized that methyl cation could lay the foundations for organic chemistry, and possibly life, across the universe.

But nobody had detected the molecule beyond our solar system until scientists pointed the Webb telescope at a young star system in the Orion Nebula, a giant star-forming region located 1,350 light-years from Earth.


A wide shot of the Orion Nebula, revealing it's iconic shape.
Eric Teske/Stellar Neophyte

There, in a ring of gas, dust, and rock orbiting a star — material that may someday coalesce into a planet — Webb spotted the first alien methyl cation known to science.


"While we have hypothesized for some time methyl cation existed in the universe, it was purely theoretical until now," Els Peeters, an astrophysicist at Western University, an expert in interstellar molecules and star formation, and a member of the team that made this discovery, said in a press release.

"We can only now prove its existence thanks to the awesome capabilities of the James Webb telescope. This is a remarkable discovery," she added.
Webb's sensitivity to light helps it detect new molecules


An artist's impression of the James Webb Space Telescope.NASA

The Orion Nebula is visible to the unaided eye under very dark skies, but it takes a powerful telescope to identify the molecules that make it.

While scientists have used other telescopes, including Hubble, to study the Orion Nebula, only Webb has the power to detect methyl cation. That's because Webb analyzes wavelengths of a type of electromagnetic radiation called infrared light coming from distant objects in space.

That's a treasure trove of information for astronomers, because each chemical element emits and absorbs light at specific wavelengths. By picking apart the infrared light shining from a star or nebula, Webb can tell scientists exactly what chemicals are present there. That's how it can detect water vapor, for example, or sand-like particles in a distant planet's atmosphere.

An international team of scientists spotted the signature of methyl cation in the wavelengths Webb captured from this distant star in the Orion Nebula. They published their findings in the journal Nature on Monday.

"This detection not only validates the incredible sensitivity of Webb but also confirms the postulated central importance of CH3+ in interstellar chemistry," Marie-Aline Martin-Drumel, a researcher at the University of Paris-Saclay and another co-author on the paper, said in a NASA press release.

Destructive UV radiation may actually help the early chemistry of life


The young star system in the center of this image contains a protoplanetary disk named d203-506.
ESA/Webb, NASA, CSA, M. Zamani (ESA/Webb), and the PDRs4All ERS Team

Some scientists wouldn't have expected to find methyl cation in the ring of material, or "protoplanetary disk," where Webb spotted the critical carbon molecule.

That's because, according to NASA, the region is being constantly bombarded with powerful UV radiation, which is known to destroy complex organic molecules.

The discovery of methyl cation there suggests that UV radiation may actually be the source of energy needed to form this particular molecule in the first place. Then, eons later, the methyl cation could help form the more UV-sensitive complex carbon molecules needed for life.

That could explain how the building blocks of life appeared on our planet. Long ago, when Earth was just a protoplanetary disk, it too was bombarded with heavy UV radiation.

"This clearly shows that ultraviolet radiation can completely change the chemistry of a protoplanetary disk. It might actually play a critical role in the early chemical stages of the origins of life," said lead author of the study, Olivier Berné of the French National Centre for Scientific Research in Toulouse.

No comments: