Astronomers spot up to 170 giant rogue planets floating through space

[PJMcK]

2. Probably not "dark matter"

This mysterious stuff doesn’t seem to interact with “normal” matter at all. We can’t see it because light doesn’t reflect off of it. The only way we know something is there is because of its gravitational effect on stuff around it.

Rogue planets are made of the regular stuff. They were probably formed in orbits around other stars but were then cast adrift by powerful gravitational forces from outside their solar systems.

Some scientists theorize that dark matter could be the gravitational influence from an adjacent universe! Crazy stuff but that’s science!

Dark matter and dark energy will probably be profound discoveries when astrophysicists figure them out.

One quibble from the article is that nothing moves through space “aimlessly.” Gravity affects everything.