Guardians of the Galaxy Vol. 3 subtly hints the Guardians recreated the Nova Corps - setting up the debut of some of Marvel Comics' greatest heroes, the Novas Richard Rider and Sam Alexander. The Nova Corps appeared in the first Guardians of the Galaxy, defenders of the planet Xandar. They were subsequently decimated offscreen before the beginning of Avengers: Infinity War, when Thanos' forces attacked Xandar and the Mad Titan took the Power Stone from them. Still, it's long been clear that wasn't the end of their story; Marvel Comics has two heroes who are part of the groups, and Marvel Studios president Kevin Feige has long claimed these Novas have "immediate potential" in the MCU.
The trailer for Guardians of the Galaxy Vol. 3 subtly hints the Guardians are either allied with, or more likely are part of, the Nova Corps. It shows the Guardians wearing new team uniforms, and they bear a logo inspired by Star-Lord's from the comics. There are some differences between the logos, though; in the comics, the flame shape is empty, but the MCU has filled it in with a design clearly inspired by the symbol of the Nova Corps. It looks as though Guardians of the Galaxy Vol. 3 will reveal the status of the Nova Corps, and their (presumably expanding) role in defending the galaxy. In doing so, it will clearly set up the potential introduction of those superheroes teased by Feige.
Guardians Of The Galaxy Vol. 3 Explains Why Marvel Is Taking So Long With Nova
Feige's initial comments about Nova were made back in 2018, which means the term "immediate potential" looks rather odd in hindsight. But it's important to remember Guardians of the Galaxy Vol. 3's delay affected Marvel's Phase 4 slate, because the film isn't only the swan song for the OG Guardians; it's also positioned as a launchpad for a new wave of cosmic films. Gunn was originally heavily involved with these plans, confirming scripts were already in the works. Gunn was fired from Marvel when old comments on social media resurfaced, with Guardians of the Galaxy Vol. 3 - and all these cosmic plans - put on hold until he was eventually rehired. It's worth noting that Marvel recently revealed their upcoming slate for Phases 5 and 6 of the shared universe - but even after these announcements, the MCU still has several unannounced films and TV shows. It's reasonable to assume many of these are projects that spin out of Guardians of the Galaxy Vol. 3, presumably including Nova.
What Is The Connection Between The Guardians Of The Galaxy & The Nova Corps?
The Guardians of the Galaxy have long had ties to the Nova Corps in the comics - especially Star-Lord, who is a close friend of Richard Rider, Earth's pre-eminent Nova. The two allied together in a number of major Annihilation events, and in the Realm of Kings epic they teamed up to trap Thanos in a twisted alternate universe called the Cancerverse. Richard Rider has often served as leader of the Nova Corps, and under his leadership they've frequently shared resources with the Guardians of the Galaxy. Thus a connection between the groups in the MCU has its basis in comics, even if the MCU is yet to introduce its version of Richard Rider.
This could explain why the Guardians have relocated to Knowhere, the severed Celestial head transformed into a mining colony. The Guardians of the Galaxy Holiday Special revealed the Guardians have purchased Knowhere from the Collector, and it's possible they are doing so on behalf of the Nova Corps - taming a previously-untamed part of the galactic frontier. It would certainly fit with the apparently unlimited resources Star-Lord has access to, allowing him to buy all the new equipment seen in the Guardians of the Galaxy Vol. 3 trailer.