Artifacts allow the player to travel to the planet that they were found on, effectively opening that planet up to exploration directly from the player's Ship via selecting that planet on the Computer Block and then using the Portal Block.
Every time the player lands on most planets, 0-4 artifacts can be found. To activate, the player simply needs to run into the artifact. A successful activation will grant 3 direct portal uses to the planet normally, 6 if the character is using the President uniform.
Artifacts do not spawn in Mech City, Old Earth, and The Forbidden Arena, and the only way to get additional direct portal uses to those places is to consume Ion Tickets, Remembrance Tickets, and Arena Tickets, respectively.