Scientists have detected sugar in the depths of interstellar space for the first time.
In a remarkable discovery, a team have identified erythrulose in the vast clouds of gas and dust between the stars.
It was found in a molecular cloud in the centre of our galaxy by two ultra–sensitive telescopes.
The researchers said based on their findings, up to 50 million tonnes of this sugar could have reached Earth’s surface when it was heavily battered by space rocks some four billion years ago.
And it raises the possibility that some of life’s essential ingredients were forged in the cosmos before reaching our young planet.
The finding is significant because sugars are among the key ingredients needed for life to exist.
‘The detection of erythrulose is very exciting because it opens up the possibility of discovering in space other sugars such as ribose, which is part of RNA, and other important molecules for the origin of life,’ said Carlos Briones, co–author of the study.
The discovery strengthens the idea that the chemical ingredients needed for life are widespread in space – which adds weight to the idea that life could have also formed on other planets.
In a remarkable discovery, a team have identified erythrulose in the vast clouds of gas and dust between the stars in the middle of the Milky Way
Sugars are essential molecules for life, providing energy and forming key components of DNA and RNA.
DNA is the primary carrier of genetic information in cells, while RNA performs numerous essential functions.
However, scientists have never been able to pinpoint how sugars originated on our planet.
‘Despite their importance, one of the major questions in origin–of–life research is how the first sugars formed on Earth, since laboratory experiments show that they do not form in enough quantities under prebiotic conditions,’ the researchers said.
‘Sugars such as ribose and glucose have previously been detected in meteorite and asteroid samples, suggesting that some of these molecules may have originated in the primordial molecular cloud from which our Solar System formed.
‘However, until now, no sugar had ever been directly detected in the interstellar medium.’
The international team identified the four–carbon sugar erythrulose in a giant molecular cloud near the centre of the Milky Way.
To confirm the discovery, they matched 12 distinct radio signals from the cloud with the unique spectral fingerprint of erythrulose measured in the laboratory.
To confirm the discovery, they matched 12 distinct radio signals from the cloud with the unique spectral fingerprint of erythrulose measured in the laboratory
‘The discovery of interstellar erythrulose suggests that the interstellar medium could be a viable source of sugar feedstock for the prebiotic synthesis of the first nucleic acids, not only on the primitive Earth but also elsewhere in the Universe,’ they said.
Further analysis revealed erythrulose could form naturally inside icy dust grains in space from much simpler molecules.
On Earth, this sugar is commonly found in raspberries and even in fake tan products.
And while erythrulose itself is not the sugar found in DNA or RNA, its discovery shows that complex sugars can form naturally in space.
That makes it more plausible that other biologically important sugars – especially ribose, which forms part of RNA – might also exist in interstellar clouds.
The findings, which the scientists described as ‘unexpected’, have been published in the journal Nature Astronomy.
Last year, NASA announced it had discovered essential sugars millions of miles away on the asteroid Bennu.
The five–carbon sugar ribose was found on the asteroid, as well as six–carbon glucose.
This marked the first time this sugar has been found in an extraterrestrial sample.
The researchers, led by a team at Tohoku University in Japan, emphasise that these sugars are not evidence of aliens.
Instead, they could provide key clues to the origins of life here on Earth.
‘Although these sugars are not evidence of life, their detection, along with of amino acids, nucleobases, and carboxylic acids in Bennu samples, show building blocks of biological molecules were widespread throughout the solar system,’ the team explained.
