Meteors Carries Life

Cosmic dust travels with meteors into the Universe and carries life in many forms. All this creats life in many planets like earth. Organic molecules in the meteorites might have helped the earlies organisms capture energy. Meteorites are ones that survived the birth of our Solar System

Otherwise known as ‘interplanetary dust particles’ or IDPs, these are tiny cousins of meteorites; or rocks from space which we can collect in the stratosphere, in deep sea sediments, or arctic ice. Most meteors are the size of a grain of sand and burn up in the atmosphere. Cosmic dust particles are about the size of a particle of smoke and because of their small sizes, most survive without ‘buring up.’
Cosmic smog may have seeded life not only on our planet, but in countless other solar systems throughout the Galaxy.

That is the implication of a new study of meteorites, which reveals that important complex organic molecules survived the formation of our Solar System and were brought to Earth on these rocks. It suggests ours and any other solar systems would have been dusted with this mix of organic ingredients very early on, giving life a head start that could make it common elsewhere. “It makes us more sanguine about finding other habitable planets,” says Max Bernstein of NASA’s Ames Research Center in Moffett Field, California. Organic molecules in the meteorites might have helped the earlies organisms capture energy. The molecules, called polycyclic romatic hydrocarbons, are common in interstellar space, and many believe they were among the raw materials for life. But until now no one knew if the PAHs in meteorites are ones that survived the birth of our Solar System, or if they formed from scratch only later. PAHs are a family of compounds composed of two or more linked benzene rings that share carbon atoms. The simplest, naphthalene, is used to make mothballs. Others, many of them carcinogenic, are components of smog and smoke from burning fuels or tobacco. PAHs are the most abundant form of carbon known in the Universe. They also make up well over half of the organic compounds in the most common type of meteorites, called carbonaceous chondrites, which have rained down on the Earth along with other cosmic dust ever since the planet formed. These meteorites contain samples of the material from which the Solar System formed 4.6 billion years ago. But it has remained unclear whether the organic components date from that time, or if they were formed or have been altered since then by exposure to space and solar radiation. To find out, chemist Richard Zare of Stanford University in California fired a sensitive laser probe at fresh slices from two different meteorites. He analysed the organic compounds released from the carbon grains in the meteorite, looking in particular at the ratio of heavier PAHs to naphthalene. Interstellar cloud
Zare reports to the American Chemical Society meeting in Boston this week that the ratio was surprisingly uniform throughout the meteorite. That means the molecules have not been altered since the rock formed, he says. Otherwise you’d expect to see a gradient, with the ratio of compounds near the outside of the meteorite looking different to that in the centre. “We’re getting a chemical snapshot of the smoggy Universe before the Solar System formed,” he says.

Although PAHs themselves aren’t found in living cells, they are easily converted into other molecules that are essential for life. Over a decade ago, chemist Everett Shock showed that PAHs could react to form amino acids. And more recently, Bernstein made important organic molecules such as alcohols and quinones by illuminating ice-coated PAHs with ultraviolet light, simulating the environment of an interstellar cloud. Researchers are now considering the possibility that PAHs themselves might have been involved in the earliest cells. “It’s possible that these meteoritic molecules on the early Earth were incorporated into the first organisms,” says Bernstein. PAHs might even have allowed primitive organisms to capture light energy in a kind of basic photosynthesis, according to chemist David Deamer of the University of California, Santa Cruz.

He has found that PAHs absorb near-ultraviolet and deep blue light, allowing them to donate electrons to other molecules, just as chlorophyll does. PAHs could be incorporated into membranes and deliver electrons, Deamer says, potentially “starting a whole chain of reactions.”

Space is a place that life ends and begins life travels to places and continues universe unites and it is not separate.