NASA has found sugar in meteorites that crashed to Earth

(CNN) Meteorites that crashed into Earth billions of years ago contain sugars, researchers say, lending support to the idea that asteroids may hold some of the ingredients to life.

An international team of scientists found "bio-essential" sugars in meteorites, which also contain other biologically important compounds, according to a press release from NASA on Tuesday.

Asteroids -- rocky near-Earth objects which orbit the sun -- are the parent bodies of most meteorites. And the theory suggests that chemical reactions within asteroids can create some of the elements essential to life.

In a study published Monday 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.

shiruken on November 21st, 2019 at 19:48 UTC »

Here's a link to the study published today in PNAS: Y. Furukawa, et al., Extraterrestrial ribose and other sugars in primitive meteorites, PNAS (November 18, 2019).

Significance: Ribose is an essential sugar for present life as a building block of RNA, which could have both stored information and catalyzed reactions in primitive life on Earth. Meteorites contain a number of organic compounds including components of proteins and nucleic acids. Among the constituent molecular classes of proteins and nucleic acids (i.e., amino acids, nucleobases, phosphate, and ribose/deoxyribose), the presence of ribose and deoxyribose in space remains unclear. Here we provide evidence of extraterrestrial ribose and other bioessential sugars in primitive meteorites. Meteorites were carriers of prebiotic organic molecules to the early Earth; thus, the detection of extraterrestrial sugars in meteorites implies the possibility that extraterrestrial sugars may have contributed to forming functional biopolymers like RNA.

Abstract: Sugars are essential molecules for all terrestrial biota working in many biological processes. Ribose is particularly essential as a building block of RNA, which could have both stored information and catalyzed reactions in primitive life on Earth. Meteorites contain a number of organic compounds including key building blocks of life, i.e., amino acids, nucleobases, and phosphate. An amino acid has also been identified in a cometary sample. However, the presence of extraterrestrial bioimportant sugars remains unclear. We analyzed sugars in 3 carbonaceous chondrites and show evidence of extraterrestrial ribose and other bioessential sugars in primitive meteorites. The 13C-enriched stable carbon isotope compositions (δ13C vs. VPDB) of the detected sugars show that the sugars are of extraterrestrial origin. We also conducted a laboratory simulation experiment of a potential sugar formation reaction in space. The compositions of pentoses in meteorites and the composition of the products of the laboratory simulation suggest that meteoritic sugars were formed by formose-like processes. The mineral compositions of these meteorites further suggest the formation of these sugars both before and after the accretion of their parent asteroids. Meteorites were carriers of prebiotic organic molecules to the early Earth; thus, the detection of extraterrestrial sugars in meteorites establishes the existence of natural geological routes to make and preserve them as well as raising the possibility that extraterrestrial sugars contributed to forming functional biopolymers like RNA on the early Earth or other primitive worlds.

Kule7 on November 21st, 2019 at 18:02 UTC »

"The research provides the first direct evidence of ribose in space and the delivery of the sugar to Earth," said Yoshihiro Furukawa of Japan's Tohoku University, lead author of the study, in the press release. "The extraterrestrial sugar might have contributed to the formation of RNA on the prebiotic Earth which possibly led to the origin of life."

I don't understand this. If the chemical processes that create Ribose are found on asteroids, wouldn't they have also likely been found on early Earth? Why do we need an extraterrestrial sugar hypothesis?

seriousnotshirley on November 21st, 2019 at 14:39 UTC »

I did a spectroscopy project in college. I was surprised to find out how much of what’s floating out in space is complex molecules rather than just elemental.

Chemical processes are everywhere.