Gateway Purple - Gateway's Purple Coins
From Lumapedia
Gateway Purple - Gateway's Purple Coins is usually the first purple coin star done in 120 star routes. Upon completion, the player unlocks the Red Star for use in the observatory, allowing for a fast mode of travel to reach the higher domes on the Comet Observatory.
The individual level world records are 1:26.466 for Mario by Tiber and 1:35.933 for Luigi by Flygonman.