Scientists have long wondered how the complex molecules necessary for life could have formed in the violent and turbulent environment of the Sun’s early days.
family meteorite “Chondrites“Meteorites are theorized to have brought the materials necessary for life to Earth, but the question remains: how did complex organic molecules containing elements such as carbon, nitrogen and oxygen get locked inside these meteorites in the first place?”
According to the new study, the “hot spots” for the formation of these macromolecules, which are the key building blocks of life, are so-calledDust trap“A disk of matter is swirling” Young StarHere, intense starlight from the central young star can irradiate the accumulated ice and dust, causing them to form carbon-containing polymers in just a few decades, which is relatively fast.
This means that the macromolecules may already be present in the larger sizes. Planetesimals form planetsor may be sealed asteroid In the form of small pebbles. These asteroids may have subsequently collided in space and broken up to form smaller objects, some of which may have reached Earth in the form of meteorites.
Related: Fascinating New Images from the Hubble Telescope Reveal the Brightness of a Young Star
“It’s exciting to discover a new and important role that dust traps play in the formation of polymeric materials that planets may need to harbor life,” Paola Pinilla, a member of the research team at the Mullard Space Science Laboratory, University of London, told Space.com. “Dust traps are beneficial areas for dust particles to grow into pebbles and planetesimals, the building blocks of planets.”
Pinilla explained that these regions are continually regenerated and replenished with tiny particles through ongoing destructive collisions. These tiny, micron-sized particles are easily lifted into the upper layers of the flat cloud of star-forming material that surrounds the young star, where they form a mass of 100 times larger than the mass of the young star. Protoplanetary disk.
Once here, Pinilla says, these particles receive just the right amount of radiation from the newborn star to efficiently convert these tiny ice particles into complex polymeric materials.
Recreating the early days of the solar system in the lab
Star-like The sun is born A protostar occurs when a dense speck forms in a giant cloud of interstellar gas and dust. The baby star gathers material from the remains of its birth cloud and accumulates the mass needed to trigger an explosion. Nuclear fusion Hydrogen is converted to helium in the core. This is the “Main sequence“The lifetime is about 10 billion years for a star around the mass of the Sun.
This young star is surrounded by a protoplanetary disk – material that wasn’t consumed during the birth of the star and its ascension to the main sequence. As the name suggests, this material and the disk are where plants form, but it also explains the origin of comets and asteroids.
Our solar system underwent this creation process approximately 4.5 billion years ago.
Previous studies in Earth-based laboratories have shown that when these protoplanetary disks are illuminated by starlight, complex molecules made up of hundreds of atoms form in them — molecules made mostly of carbon, similar to black soot or graphene.
Dust traps are places of high pressure in protoplanetary disks where molecules slow down and dust and ice particles can accumulate. The slower velocities in these regions allow the particles to grow and, in most cases, avoid the collisions that would cause fragmentation, which means they may be essential for planet formation.
The team wanted to know whether the radiation that starlight brings to these regions could trigger the formation of complex polymers, so they tested this idea using a computer model. Atacama Large Millimeter/submillimeter Array (ALMA) An array of 66 radio telescopes in northern Chile.
“Our work is a unique combination of astrochemistry, ALMA observations, laboratory work, dust evolution, and the study of meteorites from our solar system,” said team member Nienke van der Marel of Leiden University. “It’s really exciting that we can now use an observational model to explain how large molecules form.”
The model showed the team that producing polymers in dust traps is a feasible idea.
“We were of course expecting this result, but we were pleasantly surprised that it was so clear,” said team leader Niels Ligterink of the University of Bern. “We hope that this will encourage our colleagues to pay more attention to the effects of heavy radiation on complex chemical reactions. While most researchers focus on relatively small organic molecules, the size of a few tens of atoms, Chondrites contain mainly large macromolecules“
“We look forward to testing these models with further experiments and observations with powerful telescopes such as the Atacama Large Millimeter Array (ALMA) in the near future,” Pinilla concluded.
The research team’s study was published in the journal Nature on Tuesday (July 30). astronomy.
