how does one be a ''supernova''

so latley in the collesium there seems to be a few rookies with bounties over 100,000,000 but are not supernovas or is it because there can only be elven at any given time?im confused

Well, the title is given to the group of rookie pirates whom are thought to have the potential to affect the world greatly. The eleven supernovas caused (actually it was Luffy -.-), or participated in the incidence of offending a Clestial Dragon at the Shapodi island. They all also survived too when some of the greatest marine forces were there, which includes a Shichibukai and an Admiral. I think they truly deserve the title XD

soo to be come a supernova you need to:
(A.)have a bounty over 100,000,000
(B.)be noticed by the gument
(C.)reach the new world or graand line not sure