The Battle of Saturn was a conflict involving the Earth Defense Forces and the White Comet Empire. The Empire brought a large number of space carriers, battleships and numerous smaller vessels to bear against the humans, whose own forces were considerably smaller and had less advanced firepower than the invading ememy.
The White Comet Empire's plan was to attack with their scorpion fighters, which had twice the range of EDF fighters, and destroy or mortally wound the EDF fleet before the latter's large capital ships could get a bead on their counterparts. However, thanks to a surprise attack launched by the Yamato and an accompanying EDF carrier fleet, Empire's Scorpion fleet was eliminated, mostly before they could launch from their mother ships. The EDF forces took advantage of the fact that the Empire had positioned its carriers sufficiently far behind the rest of their fleet as to make it impractical to support them when the EDF sprung its surprise attack.
At the start of the battle the Comet Empire was ambushed by the Hyperion fleet, the second fleet fired at the Hyperion Fleet with impulse cannons, destroying all ships and killing most-if not all-personnel onboard the ships, afterwards the flagship of the Comet Empire regrouped all ships attempting to break through the middle of the Earth fleet and crush the remaining ships, however the Earth was moving into attack position, The fleet commander ordered the burst energy direct transport cannon to fire as it did many Earth ships were destroyed, forcing the Earth fleet to retreat to Saturn's ring, as it did so a few ships were destroyed by the cannon.
It was at that time the Yamato and the space carrier fleet came to assist the fleet by launching fighters destroying some Empire ships. In the asteroid ring the Empire's fleet was damaged by firing the cannon, the Earth fleet acted accordingly and turned around and fired at the Empire's ship destroying many ships. The Empire flagship made a suicide attack on the Earth fleet ship but was lost to intense fire by the fleet.
The White Comet arrived too late to avert the Comet Empire fleet's loss but attacked the Earth fleet, the fleet was destroyed and the Yamato was heavily damaged. the result was disastrous, morale was destroyed on Earth and Yamato was missing-presumed lost with the rest of the fleet.