How Life on Earth Could Have Started

Scientists redid an experiment and found a new possibility of how life on Earth could have started.

In the 1931 movie “Frankenstein,” Dr Henry Frankenstein howled his triumph as massive bolts of lightning crackled and Frankenstein’s monster stirred on a laboratory table, its pieced-together corpse brought to life by the power of electricity.

Electrical energy may have also sparked the beginnings of life on Earth billions of years ago. Earth is around 4.5 billion years old, and the oldest direct fossil evidence of ancient life is stromatolites, microscopic organism preserved in layers known as microbial mats. These are about 3.5 billion years old. However, some scientists suspect life originated even earlier, emerging from accumulated organic molecules in bodies of water, a mixture sometimes referred to as primordial soup.

But where did that organic material come from? Decades ago, researchers proposed that lightning caused chemical reactions in the oceans, and spontaneously produced organic molecules.

New research suggests that fizzes of barely visible “microlightning,” generated between charged droplets of water mist, could have cooked up amino acids from inorganic materials. Amino acids are life’s most basic building blocks and would have been the first step forward in the evolution of life.

For amino acids to form, they needed nitrogen atoms that could bond with carbon. Freeing up atoms from nitrogen gas requires severing powerful molecular bonds and takes an enormous amount of energy. Even microlightning has enough energy to break molecular bonds.

In 1953, chemists Stanley Miller and Harold Urey combined ammonia, methane, hydrogen and water inside a glass sphere to mimic the atmosphere of ancient Earth. They then jolted that atmosphere with electricity, producing simple amino acids. This experiment supported the theory that life could emerge from nonliving molecules.

Scientists revisited the 1953 experiment but directed their attention toward electrical activity on a smaller scale. They looked at electricity exchanged between water droplets measuring between 1 micron and 20 microns in diameter. (The width of a human hair is 100 microns.) The big droplets were positively charged. The little droplets were negatively charged. When oppositely charged droplets are close together, electrons can jump from the negative charge to the positively charged.

The researchers mixed ammonia, carbon dioxide, methane and nitrogen in a glass bulb, then sprayed the gases with water mist. A high-speed camera captured faint flashes of microlightning in the vapor. When they examined the bulb’s contents, they found organic molecules, including the amino acid glycine and uracil, a nucleotide base in RNA.

For the first time, scientists have seen that little droplets of water emit light and a spark. And that spark causes all types of chemical transformations.

Lightning is a dramatic display of electrical power, but it sporadic and unpredictable. Lightning may have been too infrequent to produce amino acids in quantities sufficient for life. Water spray, however, would have been more common than lightning. It is more likely that mist-generated microlightning constantly zapped amino acids into existence from pools and puddles, where the molecules could accumulate and form more complex molecules.

However, questions remain about life’s origins. An alternative abiogenesis hypothesis proposes that Earth’s first amino acids were cooked up around hydrothermal vents on the seafloor. Yet another hypothesis suggests that organic molecules didn’t originate on Earth at all. Rather, they formed in space and were carried here by comets or fragments of asteroids, a process known as panspermia.

What do you think is a likely explanation?

 

https://www.msn.com/en-us/news/technology/scientists-redid-an-experiment-that-showed-how-life-on-earth-could-have-started-they-found-a-new-possibility/ar-AA1BPYjK?ocid=mailsignout&pc=U591&cvid=55f7946bb40046bca0f5c028e2b5ca06&ei=38