An international team of researchers have developed a new technique to measure dark matter, using a state-of-the-art simulation of the Milky Way to test their mass-measuring method before applying it to real data. This threw up a number of surprises: they noticed that standard techniques used over the past twenty years were biased, always tending to underestimate the amount of dark matter. The researchers then developed a new unbiased technique that recovered the correct answer from the simulated data. Applying their technique to the positions and velocities of thousands of orange K dwarf stars near the Sun, they obtained a new measure of the local dark matter density.

“We are 99% confident that there is dark matter near the Sun,” says the lead author Silvia Garbari.