There are six scientists in Blast Corps, and once you've found these white-jacket clad old men, you have completed the game's first major segment. The six scientists are located in:

Ebony Coast
Ironstone Mine
Argent Towers
Oyster Harbor
Tempest City
Glory Crossing
But there's more. After the game ends, the carrier is directed to a safe place to explode, and after all of the credits roll by, a brand new set of challenges awaits you. Wait until the credits roll by to see this new bonus level.