Before license level 3:

Goto raraki restaurant in Quintown and watch the news. Meet hurt pilot in Pacifica Terminal

After license level 3:

Goto the pub in Regas and listen to the strangers conversation
Goto Argus tech in Newerth (Dr. Targas)
Goto Spanzo Bar in New New York and talk to Mouth
Goto Quintown and talk to Fasit
Attack Dragon Teeth at location according to Fasit
Meet Stan at Tuyak
Go back to Regas with Stan
Talk to Yanin the dock of New New York
Meet Mouth in Himbleton
After having license level 1 and having done everything above
Talk to Harvey Grant He will tell you to destroy all the pirate groups (4)
Then protect Hom from the attack of the Pogodyne Security Fleet
Attack Pogodyne Security Fleet
Goto Argus Tech and ask for the Anti-Matter gun
Goto Nova Research Lab
Final Mission at Gadon System E1