Key ingredients for life on Earth found in meteorites

AUSTRALIA: A fresh examination of meteorites that landed in Australia, Canada and the United States is bolstering the notion that such objects may have delivered to Earth early in its history chemical ingredients vital for the advent of life.

Scientists previously had detected on these meteorites three of the five chemical components needed to form DNA, the molecule that carries genetic instructions in living organisms, and RNA, the molecule crucial for controlling the actions of genes.

Researchers said on Tuesday they had now identified the final two after fine-tuning the way they analysed the meteorites.

Nucleobases are nitrogen-containing compounds crucial in forming DNA’s characteristic double-helix structure. Confirmation of an extraterrestrial origin of a complete set of nucleobases found in DNA and RNA buttresses the theory that meteorites could have been an important source of organic compounds necessary for the emergence of Earth’s first living organisms, according to astrobiologist and study co-author Danny Glavin of NASA’s Goddard Space Flight Center in Maryland.Scientists have been seeking to better understand the events that unfolded on Earth that enabled various chemical compounds to come together in a warm watery setting to form a living microbe able to reproduce itself.

– SYDNEY MORNING HERALD