United Earth Space Probe Agency

The United Earth Space Probe Agency (abbreviated UESPA) was an organization controlled by the United Earth responsible for space exploration.

History
UESPA evolved, in part, from the United Earth AeroNav Forces of the early 21st century.

In 2067, UESPA launched the Friendship One probe toward the Delta Quadrant, as part of a series of unmanned exploration.

By the 2130s the United Earth Starfleet had taken UESPA's place as Earth's leading exploratory agency, but the two would continue to cooperate. 

UESPA personnel also aided in the construction of the Enterprise in 2150.

UESPA continued to help control Starfleet vessels into the 2260s. James T. Kirk reported the destruction of the USS Antares (NCC-501) to UESPA. Later, Kirk informed John Christopher that UESPA was the USS Enterprise (NCC-1701)'s operating authority.

Alternate realities
In one alternate timeline the Qu was a UESPA vessel prior to capture by Klingons.

In another alternate universe, UESPA became a purely military organization after several other powers established the Interstellar Coalition. They also operated the UESS in the 2260s.