A new Story Pack has been announced for Stellaris, named First Contact which will be available on March 14th. You can check the Release DateAnnouncement Trailer below.
“You are not alone! The galaxy is vast and full of wonders, but it’s also full of alien empires you’re going to encounter, whether you’re ready or not. First Contact offers a set of new origins and mechanics that give players the chance to tell stories about their civilizations’ early encounters with visitors from the stars — ones that may not have come in peace!”