minsta

How comet Hale-Bopp may reveal the origins of life on Earth – and perhaps beyond

Pabio November 7, 2024

Comets – these small, icy objects orbiting the sun – act like floating time capsules, providing a window into the early days of our solar system’s formation and holding clues to the origins of life on Earth. Earth.

In a recent study, scientists developed a revolutionary model to trace the evolution of a comet’s chemistry, known as “Hale-Bopp,” over time. Ultimately, this endeavor succeeded in revealing information that could improve our understanding of planetary formation as a whole – and it may even have shed light on the potential for life beyond our planet.

“You’d be hard-pressed to find two comets which look completely alike,” Drew Christianson of the University of Virginia told Space.com. “Hale-Bopp has been a favorite of comet studies in part because it was one of the brightest comets observed (…) even nicknamed the Great Comet of 1997. As a result, there is a wealth of observations with which to compare our model results.

Hale-Bopp is from Oort Clouda theoretical shell of icy planetesimals surrounding the sun at the confines of our solar systemand is believed to contain some of the most primitive and best preserved remains from primordial times. nebula which formed our solar system.

“The Oort Cloud is about as far from the sun as you can get while still being in the solar system,” Christianson said.

But then, at some point in the distant past, Hale-Bopp was ejected from the Oort Cloud and began its approach toward the sun. Today, it takes about 2,400 years to complete its orbit around our star. In other words, we now have an object relatively close to us that not only contains information about the far reaches of our solar system, but also about the early days of our cosmic neighborhood.

So, using observational data collected over the years, scientists studied Hale-Bopp – particularly its chemical composition and how it might change over time – to provide valuable insight into the state of the ancient solar system. This data is also complemented by computer models that help us understand the dynamic interactions and transformations taking place within the comet, simulating how complex organic molecules may have formed, survived or broken down over time. Knowing these internal cometary interactions is important because it reveals what types of molecules might have been present in the early days of our solar system – and therefore may suggest how life began.

However, such analyzes are difficult when studying fully formed comets like Hale-Bopp, and become even trickier as the comet approaches the sun, where it heats up and spews dust and gases into a giant and luminous “coma”.

One of the main questions researchers in the new study are asking is how to distinguish the chemical species created in the comet’s ice (the “parent” species) from those formed by energetic processes in the coma (the “girls”).

Scientists have developed gas-phase chemistry models to study processes occurring in cometary comas, but current iterations of these models focus only on active comets and do not take into account the chemistry occurring in icy cores. comets. As a result, these models may not adequately capture all of the conditions and processes experienced by a comet throughout its life.

“There have been many chemical models of the gas and surfaces around comets in the past,” Christianson said. “Similarly, studies have been carried out on the physical conditions of the ice and dust of the comet itself. However, before (our model), MAGICKAL, there was no chemical model of the comet body, making it the first of its kind.

The team’s new model tracks Hale-Bopp’s orbit, starting from its cold storage phase in the Oort Cloud, followed by five of its orbits around the sun. The model divides the comet’s body into 25 distinct layers of ice and dust, with complex chemistry occurring at different depths, allowing them to better represent the true reality of the comet’s chemistry.

“When a comet is heated as it approaches the sun, it is not heated uniformly,” Christianson said. “The exterior first becomes hotter before penetrating deeper into the comet. Likewise, UV rays and cosmic rays only reach certain depths and affect each depth differently.

The Hale-Bopp core, composed of frozen water, gas, dust and rocky materials, contains complex organic molecules such as formamide, methyl formate, ethylene glycol, methanol and acetonitrile – substances that scientists suspect of being linked to the origins of life on Earth.

Interestingly, research suggests that most of Hale-Bopp’s complex organic molecules are likely inherited from its primordial origins rather than formed during its current journey. “Comets are aggregates of icy dust grains that develop during the process of star and planet formation,” Christianson said. “While dust grains are omnipresent in the interstellar mediumIn dense star-forming regions, they build ice mantles from materials in the surrounding gas while temperatures are still low. »

Scientists believe that it is within these ices that complex organic molecules are formed.

“JWST “Observations also begin to support the idea that (these molecules) are present in cold ices,” Christianson added. “Eventually, these icy grains aggregate to form larger and larger bodies that we call comets. Many complex organic molecules found in comets appear to have an interstellar origin. »

Before you can jump to conclusions, Christianson cautions that whether comets are a source of organic molecules on Earth is a highly controversial subject. “We don’t know for sure what influence, if any, early comets had on the early Earth. Our model results don’t affect the formation of the solar system much, but they suggest it was in effect of a very complex environment with all kinds of chemicals, organic or otherwise. But the organic molecules brought to a primitive Earth by comets could come from long before the formation of the Sun.

He says the team plans to further refine its model to more accurately represent real comets, with the aim of making more reliable predictions about new comets and the insights they can offer about the history of the ‘evolution. To this end, they are currently preparing a model study of comet 67P – a Jupiter-family comet that made history as the first comet to be orbited and landed by a spacecraft from Earth.

“As far as observations go, we haven’t even observed a fraction of a percent of the comets in the solar system,” Christianson said. “Most are simply out of reach. If we observe more comets and find them less complex than we initially thought, then perhaps the composition could be entirely formed within the solar system. Or, if we find more chemically complex comets, this would occur further supports the idea that the complex molecules must have been formed before the. formation of the solar system.

“Only time I’ll say it.”

Mondor Festival

Mondor Festival

How comet Hale-Bopp may reveal the origins of life on Earth – and perhaps beyond

Pabio

This robot should be used for DJI Mini 3 Pro mini drone

Balancing inheritance fairness and spotting signs of isolation

Anthony Rendon appears to be out of Angels’ plans: report

Three-Second Rule for Food: Food Type and Surface Material

How comet Hale-Bopp may reveal the origins of life on Earth – and perhaps beyond

Pabio

You Might Also Like

This robot should be used for DJI Mini 3 Pro mini drone

Balancing inheritance fairness and spotting signs of isolation

Anthony Rendon appears to be out of Angels’ plans: report

Three-Second Rule for Food: Food Type and Surface Material