The main map shows nine sectors. The game contains more. Confirmed secrets, community sightings, and a few hints from the developers, collected in one place without spoiling the good part.
The Omitted Sector
The first confirmed secret. Finishing Sector 3 without touching a single pickup opens a course with no name and no score upload. It exists only in that session. Around 4 percent of players have seen it.
The pulsar easter egg
Fly a slow orbit around the pulsar in Sector 7 for three full turns and the soundtrack crossfades into a track that does not appear on the OST. It took the community eleven months to find.
"The best secret in the game is still unclaimed. That is all we are saying."
BeardyBird, asked directlyOmega's second door
Patch 1.4 added a hidden exit inside Omega's star storm. Players who escape through it report a changed title screen the next time they launch. Nobody has fully documented what it does yet.
Things that are not secrets
No, there is no eleventh ship. No, typing your name backwards does nothing. The community wiki keeps a debunked list, and the developers confirm entries on request.
How to hunt
Every confirmed secret shares one pattern: it rewards a weird behaviour the main game never asks for. Slow down. Fly backwards. Idle on a menu too long. The game is watching for the players who stop trying to win.