The Vanguard Fleet during the early Terran Age of Discovery (02200s)

While ships of Terra did carry out significant exploration efforts during the mid- to late-02100s, the first real era of discovery began in the 02260s with the deployment of the TransFed Vanguard Exploration Cruisers.  This new line of galactic research ship was made up of vessels ranging from the diminutive Exploration Frigates to the late era Exploration DreadNaughts and consisted of both brand new designs and upgrades of earlier classes, such as that of the TFS Venture and her sister ships. 

Some of the newer TransFed VanGuard designs were merely upgraded variants of previous designs.  These ships turned out to be excellent vessels for both exploration and military purposes and many enjoyed long service lives into the late 02290s.

The 02260s also marked the first contact between Terrans and one of the Galaxy's cosmic horrors (or guardians, depending on how you look at it); the sublimely ancient Omnicrons.  Their massive vessels plied the deep space lanes, alternating between attacking and protecting the ships of Terra and her allies.

The VanGuard became the major fleet power during the First Terran Age of Discovery as their starships became commonplace throughout much of the local region of known space.  At the same time, there was significant jockeying for position and influence with other races, such as the Cronans and a newly-discovered avian species called the Pauk.  The Cronans were transplanted humans from Terra's ancient past who followed a religion of conquest and debauchery, ruling over other beings in a brutal fashion using their genetically-modification technology.  The Pauk, on the other hand, were a suspicious and devious race who saw themselves as a counter-balance to the Terrans.  With their population spread throughout dozens of nebulae, these "Warriors of the Clouds" (as they called themselves) caused fear throughout the known worlds for nearly two centuries, although at least one sect of the Pauk were nominal allies with the TransStellar Federacy on occasion.  These two races, along with other species that would rise and fall from time to time, posed the greatest threat to the Terran Ascension during the 23rd and 24th Centuries.

The vile Cronans were responsible for many of the interstellar crises that developed during the 02260s, but were overthrown circa 02270 by one of their slave races, the reptilian Zarlacks. 

Pauk warships terrorized the allied worlds during the two centuries that began around 02260 and ended roughly 02460, although they seemed to take a long hiatus here and there and hide out in their stellar nurseries from time to time.  Their treachery became the stuff of legends, and even thousands of years later the term "Paukish" still connotes a being of dishonest or duplicitous nature.