The post-credits scene in Spider-Man: Brand New Day leaves audiences with a specific mystery. The film concludes by showing the Spidey Tracker app, developed by Ned Leeds, detecting a signal far out in space beyond the moon. Because the scene contains no live-action footage or actors, the meaning remains a topic of debate for viewers.
The most prominent theory involves the upcoming Avengers: Doomsday and the concept of incursions. These cosmic events occur when two universes collide within the multiverse. The appearance of a Spider-Man signature in space might signal that the boundaries of Earth-616 are breaking down, potentially allowing other versions of the character to enter the main Marvel universe.
Another theory suggests a connection to the Fantastic Four. Fans know that the group enters Earth-616 on a rocket, and it is possible that Peter Parker hitches a ride with them for a mission. This aligns with the long-standing comic book history where Spider-Man and the Fantastic Four frequently cooperate on off-world adventures.
A third possibility links the scene to Avengers: Secret Wars. In the comic storylines, Battleworld acts as a patchwork planet formed from the remains of various universes after a total multiversal collapse. Spider-Man appearing in space could hint at his presence on this planet, rather than an immediate arrival in the next film.
Finally, some fans speculate about the return of the Symbiote. Venom originated on Battleworld in the 1980s Secret Wars comics, eventually finding its way to Earth as a black suit for Spider-Man. With a piece of the Symbiote left behind in the Marvel Cinematic Universe during No Way Home, this space signal might mark the beginning of that classic narrative arc.