NASA defines space as starting at 50 miles (~80 km), FAI defines it as 100 km (~62 miles).

Scott Manley gave a nice summary a few days ago: https://youtu.be/0b1VgtyIQN0?t=627

Here's the article he references: https://physicstoday.scitation.org/doi/full/10.1063/PT.3.459...

EDIT: Added links.

It will be interesting what is most commercially successful in the short term. I've a feeling Bransons option will be and he'll develop the option to 100km

Then again might get bought out

Trying to find this, but google results are just full of the controversy about this flight rather than information: _can_ SpaceShipTwo reach the Karman line?

Yes, everywhere except in the USA.