What Is Dark Matter?

Podcast of the Day

Melvyn Bragg and his guests discuss dark matter, the mysterious and invisible substance which is believed to make up most of the Universe. In 1932 the Dutch astronomer Jan Oort noticed that the speed at which galaxies moved was at odds with the amount of material they appeared to contain. He hypothesized that much of this 'missing' matter was simply invisible to telescopes. Today astronomers and particle physicists are still fascinated by the search for dark matter and the question of what it is.

Listen to Melvyn Bragg and guests discuss Dark Matter on the In Our Time podcast

Video of the Day

Short Article of the Day

It is thought there is five times more dark matter than normal matter in the universe, although it has yet to be detected directly. Finding it would solve one of science’s most baffling mysteries and explain why galaxies are not ripped apart by stars flying off into deep space.

However, many scientists believe time is running out for the hunt, which has lasted 30 years, cost millions of pounds and produced no positive results. The LZ project – which is halfway through construction – should be science’s last throw of the dice, they say. “This generation of detectors should be the last,” said astronomer Stacy McGaugh at Case Western Reserve University in Cleveland, Ohio. “If we don’t find anything we should accept we are stuck and need to find a different explanation, perhaps by modifying our theories of gravity, to explain the phenomena we attribute to dark matter.”

Continue reading Robin Mckie's short article: Will Scientists ever prove the existence of dark matter?

Further Reading

Astronomers can now observe every bright galaxy in the visible universe and can even see back to the cosmic "Dark Ages" before galaxies formed. Voluminous data from the never-before-seen universe are supporting exciting and counterintuitive directions of thinking. The great movie of the evolution of the universe is coming into clearer focus: we now know that throughout expanding space, as the universe evolved, vast clouds of invisible, mysterious non-atomic particles called "dark matter" collapsed under the force of their own gravity. In the process they pulled ordinary matter together to form galaxies. - Excerpt from The View From the Center of the Universe by Joel Primack

Related Topics

 Black HolesParticle PhysicsQuantum Mechanics | Science

Each day I post short quotes by great thinkers on a particular philosophical, scientific or historical topic, along with videos, interviews and articles by contemporary thinkers that explore each topic in more detail. Find me on Facebook or Twitter or enter your email below to learn about the ideas that helped shape our world.