Weytahn Crisis

In the 2050s, the Andorians terraformed a class-D planetoid which they named Weytahn, lying at a strategic position on the frontier between the Andoria and Vulcan. When Andoria refused to allow the Confederacy of Vulcan to inspect the colony in order to search for possible threats in the form of military installations, the Vulcans forcibly evacuated the planetoid. In 2097, the Weytahn Accord was signed, in which the Vulcans officially claimed Weytahn, which they named Paan Mokar, and a surveillance satellite was placed in orbit of the planetoid in order to enforce the accord.

As part of the 2097 Weytahn Accords, the Vulcan-controlled 47 Ursae Majoris-system was ceded to the Andorians, and settlers arrived the following year. Eleven-months after the colony was abandoned when most of the local plant life proved toxic to species to cobalt-based blood, namely Andorians. The result was the Andorians believed the Vulcans had intentionally ceded the planet knowing it was dangerous for Andorians.