This ship part can be found near the landing site in the Forest of Hope by braking the stone wall in the landing zone with Bomb Rocks, then the Pikmin must defeat all of the Bulborbs. Then, they must brake the black wall not to far from the landing zone, after braking this, there is a few more Bulborbs that must all be defeated and it can be found. It takes thirty Pikmin to carry it, and the maximum number to carry it is fifty.
I've found the Nova Blaster!
This emites a dazzling burst of light capable of destroying almost anything! I'm net exactly sure about this, but the promotional brochure claims that its blasts can travel in the currents of space-time, smashing through stars and into the rifts of space."
Click on a ship part