Tantalising traces of the building blocks of life have been spotted in nearby galaxies. However, working out the identity of these carbon-containing molecules, and when they became abundant, is proving tricky, say astronomers.

Astrophysicists believe that organic molecules were present in the cloud of dust and gas from which our solar system formed, providing the raw materials for life on Earth. Astronomers can see these molecules throughout our galaxy, which is one reason why many believe conditions may also be ripe for life in other parts of the Milky Way, and perhaps further afield.

So the hunt is on to find these molecules in other galaxies. By looking at galaxies similar to our own, but at an earlier stage of their evolution, astronomers hope to work out how long these molecules have been abundant in the universe, and therefore how long the conditions suitable for life as we know it have prevailed.