The Hidden 95% of the Universe

The Hidden 95% of the Universe

2021, Science  -   2 Comments
Ratings: 8.13/10 from 23 users.

In the early 1990s two teams of astronomers had set out to measure just what the universe was made of. These two teams known as the "High-Z Supernova Search Team" and the "Supernova Cosmology Project" brought together astronomers from around the globe with the goal of charting cosmic expansion over the life of the universe.

The astronomers expected the presence of all the matter and radiation in the universe to act like a drag on the expansion, steadily slowing it as the cosmos aged. By measuring this deceleration all the matter and energy that make up the universe would be revealed.

These international collaborations used the world's mightiest telescopes such as the eight-meter Keck telescope in Hawaii and orbiting Hubble space telescope, to scour the sky. Their target was supernovae acting as beacons of the distant cosmos whose brightness, as measured through our
telescopes, revealed how the universe had expanded as their light traveled for billions of years.

But the astronomers were in for a shock. Our universe is not slowing down, it is speeding up. After repeatedly searching for flaws in their observations and checking their calculations they presented their conclusions to a startled world. And to account for this accelerated expansion there was something else in the universe, something unexpected driving the cosmos faster and faster.

And whilst there must be immense quantities of this stuff for the effect to take place it remained and remains totally invisible to our telescopes. Whatever is out there between the stars
and galaxies accelerating the expansion, it is truly dark.

And as 1998 dawned we realized that even this dark matter was significantly outweighed by the presence of the newly discovered dark energy. Two vast components of the cosmos unseeable and for millennia undetectable. It is currently the biggest question in cosmology. What are these new components of our universe, how do they work and where did they come from?

More great documentaries


Oldest Most Voted
Inline Feedbacks
View all comments
9 months ago


Jean Corriveau
Jean Corriveau
1 year ago

This is the clearest coverage of cosmology. It allows me to connect concepts.