What Is Dark Matter Day?

On and around October 31, 2017, the world will celebrate the historic hunt for the unseen—something that scientists refer to as dark matter. Local events planned by institutions and individuals around the planet will engage the public in discussions about what we know about dark matter, and about the many present and planned experiments that seek to solve its mysteries.

Plan a Dark Matter Day Event

Want to plan a Dark Matter Day event in your community? We can help! Check out the links below to resources that can help you find and connect with local dark matter experts, plan a program for a particular audience, and promote and share your event with the world.

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What is Dark Matter?

There’s more to the universe than stars, planets, asteroids, comets, and space dust. In fact, there’s a lot more to the universe that we can’t yet explain.

Scientists believe that dark matter, which we have so far only detected through its gravity-based effects in space, makes up about a quarter (26.8 percent) of the total mass and energy of the universe, and something that is driving the universe’s accelerating expansion—which scientists call dark energy—accounts for another 68.3 percent. The ordinary matter, like stars and planets and galaxies, makes up just 4.9 percent of the total mass and energy of the universe. So there’s a BIG part of the universe that we don’t know much about. We’re not sure if dark matter is made up of undiscovered particles, or if it can be explained by tweaking the known laws of physics. Its makeup could teach us much about the history and structure of our universe.