Sonsorra was a Borothan warp field theorist who was one of the passengers on a transport ship to view the energy burst of the Great Plume of Agosoria in 2151.

He and his fellow observers were invited aboard Enterprise NX-01. Upon boarding the spacecraft, he offered a special liquor called voo-sinteel as a gift to Tucker, stating it "enhances the experience" when viewing the Great Plume. (ENT: "Cold Front")

Sonsorra was played by actor Leonard Kelly-Young who was credited as "Leonard Keely-Young" in the end credits.
His costume from this episode was later sold off on the It's A Wrap! sale and auction on eBay. [1] [2]