Space mine

Hornet space mines aboard the prowler UNSC Nereid.

Space mines are a class of naval weaponry employed by warships of the United Nations Space Command and Covenant. They function similarly to ground landmines, though are generally deployed in space to ward off the passage of other spacecraft.

Human space mines

For humanity, there are two major naval mines in service within the UNSC Navy; the M1011 Moray and the M441 Hornet. The former of the two is a conventional explosive employed aboard smaller warships and larger strikecraft, including the Winter-class prowler and various iterations of the GA-TL1 Longsword. By contrast, the Hornet is a 30 megaton nuclear explosive employed aboard the much larger Sahara-class heavy prowlers, for use in seeding orbital space against capital ships. The use of nuclear mines aboard prowlers is a gambit for the captain of the vessel, as emerging from slipspace with the mines aboard risks emitting a burst of Čerenkov radiation - resulting in a captain having to weigh up whether to drop the mines into slipspace before emerging, or to risk detection.

Space mines can be useful in an ongoing space battle, as they can be deployed into the vector of an enemy fleet while they are distracted in combat. During the Onyx Conflict, UNSC Dusk used this to great effect to destroy a number of Covenant starship and prolong the survival of Admiral Carl Patterson's battlegroup.

Covenant space mines

The Covenant have not been observed to employ dedicated space mine systems, unlike their human counterparts. However, they are capable of using plasma torpedoes for the same purpose.

Netherop mine shell

In order to prevent Nizat from being rescued by the return of a loyal captain, the Silent Shadow had the Fleet of Swift Justice establish an orbital mine shell around Netherop which Nizat acknowledged was something that he himself would've done. Following the fleet's departure, Nizat witnessed the destruction of five vessels that were presumably trying to rescue him, ships that fell victim to the mine shell. The presence of the mine shell also kept the UNSC from being able to launch a rescue mission for Lieutenant Commander Amalea Petrov and her forces that had gotten stranded on the planet.

About a year after the Battle of Netherop, the UNSC sent a rescue mission. A Prowler sneaked into orbit and established contact with Petrov. However, the orbital mine shell destroyed both Pelicans that were sent to Netherop's surface. Not prepared to clear a full mine shell and unwilling twenty lives to save eight, the captain called off the mission, but he promised that a better-equipped mission would come back when it was feasible. True to the Prowler captain's word, the corvette UNSC Alpina came years later and worked to punch through the mine shell. On the third day, the Alpina made contact with the UNSC survivors and promised that a Pelican would collect them before the next evening, having apparently found a way through the mine shell. However, Nizat was able to use the Divine Hand to destroy the Alpina and the third rescue mission that came after it.

In November 2559, seeking a weapon that could destroy Cortana's Guardians, the Swords of Sanghelios visited Netherop. Arbiter Thel 'Vadam had high kaidon Olabisi Varo'dai coordinate an effort to dismantle the orbital mine shell in order to make it safe for his forces to land. Varo'dai's medium Covenant destroyer shepherded a swarm of Seraphs that flitted in and out of low orbit and used decoys and five-craft protective formations to laboriously clear out the mine shell. Observing the efforts to dismantle it, Thel was left wondering who had placed the shell around the planet in the first place. From their launching delay when a decoy passed one of the mines and their corkscrewing approach pattern, Thel was able to identify them as self-targeting Jaet-pattern plasma torpedos from early in the Human-Covenant War, but the Covenant World Registry made no mention of an orbital mine shell around Netherop, just the loss of the Radiant Arrow and the Steadfast Strike and that the Prophet of Truth had deemed the losses to be a sign of divine displeasure and forbade all Covenant vessels from entering the system. As observed by the Banished, by the time that the UNSC Hidden Point arrived, the Sangheli had spent three quarters of a cycle clearing out the mine shell and only needed another twenty units to finish the job. Once the orbital mine shell was finally cleared out, UNSC and Sangheli forces were able to descend to Netherop's surface, although the UNSC Pelicans were destroyed by Nizat with the Divine Hand.

List of appearances

• Halo: Ghosts of Onyx (First appearance)
• Halo: Retribution
• Halo: Oblivion
• Halo: Outcasts