A few layers of water ice—the width of a strand of DNA—are starting to impact Euclid's vision; a common issue for spacecraft in the freezing cold of space, but a potential problem for this highly sensitive mission that requires remarkable precision to investigate the nature of the dark universe.

Scientists are trying to melt a thin layer of ice that is increasingly clouding the vision of the "dark universe detective" space telescope Euclid, the European Space Agency said on Tuesday.

It is the latest of several technical setbacks for the wide-eyed telescope, which blasted off into space in July on a mission to chart a third of the sky.

By doing so, the ESA hopes Euclid will reveal out more about the nature of dark matter and dark energy, which are thought to make up 95 percent of the universe but remain shrouded in mystery.

During checks in November, the team on the ground first noticed that they were losing a little light coming into the telescope's visible light imager, Euclid instrument operations scientist Ralf Kohley told AFP.