NASA has found sugar in meteorites that crashed to Earth

An international team has found sugars essential to life in meteorites. The new discovery adds to the growing list of biologically important compounds that have been found in meteorites, supporting the hypothesis that chemical reactions in asteroids – the parent bodies of many meteorites – can make some of life’s ingredients. If correct, meteorite bombardment on ancient Earth may have assisted the origin of life with a supply of life’s building blocks.

In a study published in the Proceedings of the National Academy of Sciences, researchers analyzed three meteorites, including one that landed in Australia in 1969 and dates back billions of years. Previous studies have also tried to investigate the meteors for sugar — but this time, researchers used a different extraction method using hydrochloric acid and water. The researchers found sugars like arabinose and xylose — but the most significant finding was ribose.

The team discovered the sugars by analyzing powdered samples of the meteorites using gas chromatography-mass spectrometry, which sorts and identifies molecules by their mass and electric charge. They found that the abundances of ribose and the other sugars ranged from 2.3 to 11 parts per billion in NWA 801 and from 6.7 to 180 parts per billion in Murchison. 

Since Earth is awash with life, the team had to consider the possibility that the sugars in the meteorites simply came from contamination by terrestrial life. Multiple lines of evidence indicate contamination is unlikely, including isotope analysis. Isotopes are versions of an element with different mass due to the number of neutrons in the atomic nucleus. For example, life on Earth prefers to use the lighter variety of carbon (¹²C) over the heavier version (¹³C). However, the carbon in the meteorite sugars was significantly enriched in the heavy ¹³C, beyond the amount seen in terrestrial biology, supporting the conclusion that it came from space.

Now, the researchers will continue to analyze the meteorites to see how abundant these sugars are and how they may have influenced life on Earth. This study adds to a growing list of evidence that meteorites may have led to terrestrial life. Last year, researchers found that two meteorites held other ingredients for life: amino acids, hydrocarbons, other organic matter, and traces of liquid water that could date to the earliest days of our solar system.

Sources: NASA.gov , CNN Edition