From ROI Wiki

The Spartacus is a warp powered Earthfleet dreadnought of the Romano class that served in the fleet in the years prior to the birth of the Shipkillers, and was eventually retired in the years shortly after The Battle of the Oort Perimeter. It fought its last official battle during the events of Homeworld where it engaged, and ultimately defeated Black Orchid's only starship, the Predicator in a pitched battle high above Earth's moon. And, it did this while operating on a minimum of warp fuel, limited weapons, and limited shields. Even so, it came out the victor in the fight, surviving long enough to defeat the Predicator before running out of power. It was then towed back to the Society Starship Museum and placed on display where it is still parked to this day.