All of the stars and planets and other visible matter in the universe only make up about five percent of its mass. Another 20 percent is thought to be mysterious dark matter and the remaining 75 percent to be dark energy, neither of which emit light, nor have ever been conclusively detected by scientists. But today, an international group of researchers reported that they have begun to unravel that mystery using a $1.6 billion instrument located aboard the International Space Station, designed specifically to probe for evidence of dark matter.

"Consistent" with dark matter, but not enough to rule out other explanations

The first results of the Alpha Magnetic Spectrometer (AMS) instrument include an abundance of a type of particle called a positron that is "consistent" with dark matter, but not enough to rule out other explanations, according to CERN, which helped develop and continues to oversee the instrument. The US Energy Department, which also helped fund the experiment, specifically said that the data did not yield a "smoking gun" when it came to locating dark matter at this time.

Still, researchers said that they will be able to tell for certain if the positrons they found are evidence of dark matter after a few more months of observations. The AMS instrument was installed aboard the space station in 2011. “When you take a new precision instrument into a new regime, you tend to see many new results, and we hope this this will be the first of many,” said a spokesperson for the experiment, CERN's Samuel Ting. Until then, we'll all just have to be content waiting in the dark.