Doctor Pran Tainer was an Atrean geologist, and the husband of Dr. Juliana Tainer.
In 2370, the Tainers discovered that the magma on their homeworld Atrea IV was cooling, which posed a significant threat to the continued habitability of the planet. The starship USS Enterprise-D was sent to assist in finding a solution to this problem. While investigating, Juliana was involved in an accident which revealed that she was, in fact, a Soong-type android constructed by Dr. Noonien Soong, Data's creator. She had been created in the image of then Soong's wife Juliana when she was injured in, and ultimately died from, the attack by the Crystalline Entity on the Omicron Theta colony in 2338. Pran was unaware of her true nature, as was Juliana.
The Tainers developed a technique known as ferro-plasmic infusion which would relieve the problem on Atrea IV for centuries. (TNG: "Inheritance")
Pran Tainer was played by actor William Lithgow.
His costume was later sold off on the It's A Wrap! sale and auction on eBay. [1] [2]