science

No, this study didn't deal with dark matter, that's not the missing matter they're taking about. They've known that the ordinary matter in the galaxies only accounts for a small fraction of the matter in the universe, and there were theories about how much matter was in the space between galaxies. This study looked at radio waves being emitted by distant sources, and looked at how much those waves were defracted by pasted through matter, which corroborated that yes, there's a lot of matter between galaxies.