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The Bright Night Skyep3
Does dark matter really matter?
Dr. Harry CliffDr. Harry CliffHD, subtitles, Q&ATranscript39m
We are all surrounded by an unseen, invisible world; a world made of mysterious substances that we can’t see or touch: the Dark Universe. But if we can’t see it, touch it, or detect it, why do we think it is there?

Over the final decades of the 20th-century astronomers realised that most of the Universe is missing. When we look up into space with our most powerful telescopes we are only glimpsing a tiny fraction of what’s out there. In fact, every galaxy, every star, every planet, and every spec of dust in the night sky accounts for just 5% of the Universe.

The remaining 95% is completely unknown, dominated by enigmatic substances called dark matter and dark energy. Today, scientists from all over the world are trying to prize open a window into this hidden world, a scientific mission with the potential to transform how we think about the cosmos and our place in it. 

In this fascinating talk, particle physicist Dr. Harry Cliff takes us on a tour of the Dark Universe, revealing how we came to realise that most of the Universe is missing, and telling the story of the ongoing quest to discover its true nature. 

Why do we believe dark matter is there and why is it important to us to understand it? 

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HD, subtitles, Q&ATranscript

The Bright Night Sky

For centuries, we have been looking up to the sky to understand the mysteries that surround us. The sky might hold the answers to some of our deepest questions such as where we came from. But what do we know so far?

4 talks
Interactive Q&A
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Top audience questions
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How do you measure/estimate the mass of a galaxy?
8 votes
How would you be able to tell it is a dark matter particle and not another kind of particle?
8 votes

Superb talk, a mind bending subject articulated brilliantly Peter
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