Thom-293 was a SPARTAN-III commando who served as a member of the UNSC Navy during the Human-Covenant War. He was a member of Noble Team until his death in spring 2552.
Death
During a battle on an unknown colony world on April 22, 2552, Thom participated in an operation put together by LCDR Catherine-B320 to destroy a CCS-class Battle-cruiser maintaining position above a city. However, the Lieutenant Commander, who carried the tactical nuclear weapon intended to destroy the Covenant ship, was incapacitated while on her way to the objective by an enemy Banshee.
Thom was the first to arrive to where Kat was wounded, and immediately picked up the nuke and used his Jetpack to fly into the battlecruiser without waiting for his teammates. Once inside, he threw the nuke into a staging area and attempted to escape the ship before it went off, without success. The nuke detonated before Thom could safely make it out, destroying the ship but killing Thom in the process.
Replacement
Both Commander Carter-A259 and Lieutenant Commander Catherine-B320 took responsibility for Thom's death, unable to admit that his death was his own fault. The team's commanding officer, Colonel Urban Holland, asserted that Thom died because he chose to attack Covenant forces without waiting for backup. Thom was replaced on Noble Team by SPARTAN-B312 (you) a few months later, just prior to the Fall of Reach.
http://www.youtube.com/watch?v=DKRlWLDWhGI
Direct Link: Deliver Hope Trailer
In the Deliver Hope trailer, Thom is seen wearing a gray Mark V MJOLNIR Armor with jetpack and a Mark V[B] helmet with the HUL and the CNM attachments, and FJ/PARA knee guards. It is possible that Bungie's image of Noble Six is based on Thom or vice versa.
Source: halo.wikia.com
