Nasa says its “crisp, sweeping surveys will help scientists investigate dark energy and dark matter, discover and characterise exoplanets, map billions of galaxies, study black holes, and explore objects from our own solar system to the edge of the observable Universe.”

Dark matter, which is invisible, acts as a kind of gravitational glue, while dark energy is believed to be a repulsive force driving the Universe’s expansion. Together, they are thought to make up about 95% of the Universe.

“One of our main goals at Nasa is answering the question: are we alone in the Universe?” Fox said at a Sunday morning news conference.

“With Roman, we are going to make this giant leap forward… that is going to allow us to look at these distant, distant worlds and start to really resolve the atmosphere around them to let us know: could they be habitable?”

Millard said, through the work of telescopes like Roman, scientists are hoping to create “enormous cosmic maps” of the Universe at various stages.

“They’ll be almost like an onion, so you can peel back layer upon layer… and see how the distribution of galaxies changes through cosmic time,” she said.

“What we want to do is use this distribution to try and figure out dark matter and dark energy because we know they exist, we see their effects, but what they are is a real mystery.”