Science

Life On Earth Possibly Came On A Comet

Ribose is one of the building blocks of our genes and forms a structure called RNA that helps our cells make protein.

Ribose is a sugar that forms the backbone of RNA, the latter being more primitive than DNA and believed to have been one of the first molecules characteristic of life to appear on Earth.

Scientists have long speculated about the origin of these biological compounds. Some believe the Earth was seeded by comets or asteroids that contained the basic building blocks needed to form such molecules. Doesn’t this mean that the exact same thing could have happened elsewhere in the universe?

For the first time, scientists have demonstrated that ribose can form in the ice on comets.

Several amino acids, the components of proteins, and nitrogenous bases which form nucleic acids have already been found in meteorites, and artificial laboratory comets yet Ribose has never been detected.

Today, everything we thought we knew has changed. By simulating the evolution of the interstellar ice making up comets, the researchers have successfully obtained ribose, a key step in understanding the origin of RNA, and consequently life. This is the first explanation of its kind and it is nothing less than thrilling. The discovery adds to evidence comets seeded life here more than four billion years ago.

Dr Cornelia Meinert from the University of Nice-Sophia Antipolis, said the diversity and abundance of sugars suggest they were formed from formaldehyde, a molecule found in space and on comets that forms in large quantities from methanol and water. ‘Our results suggest the generation of numerous sugar molecules, including ribose, may be possible from photochemical and thermal treatment of cosmic ices in the late stages of the solar nebula,’ said Dr Meinert.

The existence of ribose in real comets remains to be confirmed, and we hope further research will confirm the ‘real-deal’ soon enough.