Based on the current best measurements of the large-scale structure of the universe, 73% of the total mass-energy is cosmological constant, a.k.a. dark energy; of the remainder, 90% is dark matter of various sorts. The remainder is 90% intergalactic gas, and the rest luminous matter.
For short: 97% of the universe is poorly understood; 3% is hot air; and the rest is on fire.
Any resemblance to other projects is purely coincidental, I promise.