Skirmish at Theta Ursae Majoris

The Skirmish at Theta Ursae Majoris System was an engagement in the Theta Ursae Majoris System during the Insurrection. It was fought by the Bellicose, a captured UNSC frigate fighting on the Insurrectionist side, and the first UNSC ship armed with a Magnetic Accelerator Cannon, the UNSC Gorgon. The Gorgon was commanded by Captain Preston Cole, an officer whom the UNSC Navy was actively promoting as a hero. The Bellicose was commanded by Lyrenne Castilla, whose civilian identity was as yet unknown to the UNSC.

Background
Prior to the skirmish, the Gorgon and the Bellicose had met twice in battle, and on both occasions the Insurrectionist frigate managed to escape.

When they met for the third time on June 2, 2501 the Gorgon had engaged in two battles in the past seventy-two hours, and as such had severely depleted munitions and a weary crew.

Upon encountering one another the two ships battled for 34.7 minutes, peppering one another with Archer Missile, until the Gorgon slung around a planetoid to come around for a killing shot with its MAC, a weapon which no ship had yet evaded. As the Gorgon fired its last tungsten slug, the Bellicose fired the last of its missiles and detonated them prematurely, pushing the frigate out of the path of the slug.

Both vessels were left nearly or completely out of offensive ordnance. As the two ships drifted in space, their commanders engaged in a text message-only tête à tête. Castilla was aware of Cole's identity, but he was unaware of hers. With no hope of defeating each other, the two ships went their separate ways. Cole remained confident that the two ships would meet again.

Aftermath
Later that year Cole met Castilla while on leave on the UNSC colony of Roost in the Lambda Aurigae System. After a romance lasting more than a year the two were married in November 2502. However in June 2503 Lyrenne Castilla's identity as a high-ranking member of the insurgency was discovered by the UNSC. Cole was given a chance to bring her in himself, however when he returned to their home on Roost he found only a printout from the text-only exchange from their skirmish more than two years before, revealing that she was the captain of the Bellicose.