Inside a laboratory nestled above the mist of the forests of South Dakota, scientists are searching for the answer to one of science's biggest questions: why does our Universe exist?

They are in a race for the answer with a separate team of Japanese scientists – who are several years ahead.

The current theory of how the Universe came into being can't explain the existence of the planets, stars and galaxies we see around us. Both teams are building detectors that study a sub-atomic particle called a neutrino in the hope of finding answers.

The US-led international collaboration is hoping the answer lies deep underground, in the aptly named Deep Underground Neutrino Experiment (Dune).

The scientists will travel 1,500 metres below the surface into three vast underground caverns. Such is the scale that construction crews and their bulldozers seem like small plastic toys by comparison.

The science director of this facility, Dr Jaret Heise describes the giant caves as "cathedrals to science".

Dr Heise has been involved the construction of these caverns at the Sanford Underground Research Facility (Surf) for nearly ten years. They seal Dune off from the noise and radiation from the world above. Now, Dune is now ready for the next stage.

"We are poised to build the detector that will change our understanding of the Universe with instruments that will be........

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