Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Is life the rule or the exception? The answer may be in the interstellar clouds

29.05.2002


Is life a highly improbable event, or is it rather the inevitable consequence of a rich chemical soup available everywhere in the cosmos? Scientists have recently found new evidence that amino acids, the `building-blocks` of life, can form not only in comets and asteroids, but also in the interstellar space. This result is consistent with (although of course does not prove) the theory that the main ingredients for life came from outer space, and therefore that chemical processes leading to life are likely to have occurred elsewhere. This reinforces the interest in an already `hot` research field, astrochemistry. ESA`s forthcoming missions Rosetta and Herschel will provide a wealth of new information for this topic.



Amino acids are the `bricks` of the proteins, and proteins are a type of compound present in all living organisms. Amino acids have been found in meteorites that have landed on Earth, but never in space. In meteorites amino acids are generally thought to have been produced soon after the formation of the Solar System, by the action of aqueous fluids on comets and asteroids - objects whose fragments became today`s meteorites. However, new results published recently in Nature by two independent groups show evidence that amino acids can also form in space.

Between stars there are huge clouds of gas and dust, the dust consisting of tiny grains typically smaller than a millionth of a millimetre. The teams reporting the new results, led by a United States group and a European group, reproduced the physical steps leading to the formation of these grains in the interstellar clouds in their laboratories, and found that amino acids formed spontaneously in the resulting artificial grains.


The researchers started with water and a variety of simple molecules that are known to exist in the `real` clouds, such as carbon monoxide, carbon dioxide, ammonia and hydrogen cyanide. Although these initial ingredients were not exactly the same in each experiment, both groups `cooked` them in a similar way. In specific chambers in the laboratory they reproduced the common conditions of temperature and pressure known to exist in interstellar clouds, which is, by the way, quite different from our `normal` conditions. Interstellar clouds have a temperature of 260 °C below zero, and the pressure is also very low (almost zero). Great care was taken to exclude contamination. As a result, grains analogous to those in the clouds were formed.

The researchers illuminated the artificial grains with ultraviolet radiation, a process that typically triggers chemical reactions between molecules and that also happens naturally in the real clouds. When they analysed the chemical composition of the grains, they found that amino acids had formed. The United States team detected glycine, alanine and serine, while the European team listed up to 16 amino acids. The differences are not considered relevant since they can be attributed to differences in the initial ingredients. According to the authors, what is relevant is the demonstration that amino acids can indeed form in space, as a by-product of chemical processes that take place naturally in the interstellar clouds of gas and dust.

Max P. Bernstein from the United States team points out that the gas and dust in the interstellar clouds serve as `raw material` to build stars and planetary systems such as our own. These clouds "are thousands of light years across; they are vast, ubiquitous, chemical reactors. As the materials from which all stellar systems are made pass through such clouds, amino acids should have been incorporated into all other planetary systems, and thus been available for the origin of life."

The view of life as a common event would therefore be favoured by these results. However, many doubts remain. For example, can these results really be a clue to what happened about four billion years ago on the early Earth? Can researchers be truly confident that the conditions they recreate are those in the interstellar space?

Guillermo M. Muñoz Caro from the European team writes "several parameters still need to be better constrained (...) before a reliable estimation on the extraterrestrial delivery of amino acids to the early Earth can be made. To this end, in situ analysis of cometary material will be performed in the near future by space probes such as Rosetta ..."

The intention for ESA`s spacecraft Rosetta is to provide key data for this question. Rosetta, to be launched next year, will be the first mission ever to orbit and land on a comet, namely Comet 46P/Wirtanen. Starting in 2011, Rosetta will have two years to examine in deep detail the chemical composition of the comet.

As Rosetta`s project scientist Gerhard Schwehm has stated, "Rosetta will carry sophisticated payloads that will study the composition of the dust and gas released from the comet`s nucleus and help to answer the question: did comets bring water and organics to Earth?"

If amino acids can also form in the space amid the stars, as the new evidence suggests, research should also focus on the chemistry in the interstellar space. This is exactly one of the main goals of the astronomers preparing for ESA`s space telescope Herschel.

Herschel, with its impressive mirror of 3.5 metres in diameter (the largest of any imaging space telescope) is due to be launched in 2007. One of its strengths is that it will `see` a kind of radiation that has never been detected before. This radiation is far-infrared and submillimetre light, precisely what you need to detect if you are searching for complex chemical compounds such as the organic molecules.

Monica Talevi | alphagalileo

More articles from Physics and Astronomy:

nachricht APEX takes a glimpse into the heart of darkness
25.05.2018 | Max-Planck-Institut für Radioastronomie

nachricht First chip-scale broadband optical system that can sense molecules in the mid-IR
24.05.2018 | Columbia University School of Engineering and Applied Science

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

When corals eat plastics

24.05.2018 | Ecology, The Environment and Conservation

Surgery involving ultrasound energy found to treat high blood pressure

24.05.2018 | Medical Engineering

First chip-scale broadband optical system that can sense molecules in the mid-IR

24.05.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>