HOUSTON  –  Astronomers have detected a natural sugar found in raspberries in clouds of interstellar dust and gas near the center of the Milky Way galaxy. The sweet discovery shows for the first time that compounds that are key to life can form in the vast expanse between stars and fuels optimism that other molecules important for the origins of life might be found in space. A team led by astronomers at Spain’s Center for Astrobiology detected the sugar, called erythrulose, which is made of four carbon atoms. Sugars play a pivotal role in living systems, helping to provide energy, build biological structures and form parts of genetic material such as RNA and DNA. To make the observations, the team used two radio telescopes, one at the Yebes Observatory north of Madrid and the other at the Institute for Radio Astronomy in the Millimeter Range, known as IRAM, in the Sierra Nevada in southern Spain, to study a molecular cloud known as G+0.693−0.027 near the center of the galaxy.

Researchers identified the sugar by comparing its molecular signature in the radio wave data from the molecular cloud with the wavelength pattern for erythrulose measured in the laboratory. The team initially searched for simpler sugars with three carbon atoms but didn’t find any.  “This finding was unexpected, as the prevailing view in astrochemistry is that interstellar molecules grow in size through the sequential addition of carbon atoms,” Izaskun Jiménez-Serra, an astronomer at the Center for Astrobiology in Madrid and the Spanish National Research Council, said in a statement. Jiménez-Serra was the lead author of the research, which published Monday in the journal Nature Astronomy.  “Our discovery demonstrates that relatively complex sugars can already be synthesized in interstellar space, before stars and planets are born,” she added via email.

The study suggested that erythrulose can be made from simpler molecules on icy dust grains in space and may then become part of more complex chemical systems. Scientists have detected more than 340 molecules in the matter and gases that exist in the Milky Way’s interstellar space the but no sugars, the study noted.