What is the primary driver of rotational velocity differences observed between spiral galaxies?

Answer

Mass

Observations show that the most massive galaxies spin significantly faster than less massive ones, suggesting that mass is the main influence on rotational velocity.

What is the primary driver of rotational velocity differences observed between spiral galaxies?

#Videos

The Fastest Spinning Galaxy | Space is Weird - YouTube

galaxygalaxiesastronomySpinspiral galaxiesrotation speed