ABOUT DARK MATTER DAY
On and around October 31, 2021, the world celebrated the hunt for the unseen—something that scientists refer to as dark matter. Local events organized by institutions and individuals around the planet explored its mysteries and highlighted the experiments that could bring us closer to solving them. Since then, Dark Matter Day has become an annual celebration with labs around the world taking part.
Less than 5 percent of the total mass and energy in the universe is the stuff we know about: like stars, planets, galaxies, and gases. Dark matter makes up about 85 percent of the total mass of the universe, and about a quarter (26.8 percent) of the universe’s total mass and energy. Almost 70 percent (68.3 percent) of the universe’s mass and energy is composed of dark energy, another big mystery to scientists that is causing the accelerated expansion of the universe.
