During this tracking, there were 12 significant time delays that could be candidates for unknown objects in space, based on the changes of these eight pulsars. Some of these candidates were relatively small, such as one which was about a fifth of the size of the sun.
While the objects have been identified, what they are exactly still remains uncertain. There are several bodies in space that would make sense. Potentially, they could be rogue planets, dwarf stars, dark matter, or something else entirely.
“I have been warned not to call them planets, not to call them dark matter, just call them mass concentrations because, just by looking in the radio, you can’t determine what they are. I can’t even guarantee that they’re dark. They could be a brown dwarf or some sort of a white dwarf or something else.”