Space Combat - Missiles

In the New Diasporia Universe, at TL A at any rate, space combat is dominated by the missile. Energy weapons, especially among the largest ships, are formidable weapons with very great ranges. In single ship actions, especially between relatively small vessels at very close range, energy weapons are very effective. In fleet actions missiles are the deadliest weapons.
The Legion has standardized on offensive missiles in 2 standard sizes, 250 mm 6 cf missiles and 500 mm 30 cf missiles. Other armed ships inside the Union tend to use these same missile sizes. Because much of the weapon technology of the nearer Midland worlds tends to originate in the Highlands these sizes are also common there,
The typical light missile is a kinetic kill weapon, primarily a heavily stealthed B/G engine with a mass of collapsed matter for a warhead and a brilliant compact computer guided by a sensor targeting array. Topping out at 700G acceleration and with an endurance of 15 minutes and a range of almost 2 million miles light missiles are formidable weapons, even against a target with a force field, if you throw enough of them at it.
Heavy missiles are even more versatile. Topping out at 1000G acceleration and with an endurance of 18 minutes and a range of 3 miles heavy missiles can carry a variety of payload packages, including nuclear and X-Ray laser warheads.

Viper anti-missile have a crushing 10,000G acceleration, but only have a 3 minute endurance, but they can still have a range of a million miles of powered flight. A heavy missile can deliver 10 Viper anti-missiles, extending the usable range of these lethal fire and forget weapons. They can also be fired from a gravity pulse launcher, which conveys an even higher initial acceleration, extending their range. Vipers typically contain a force field warhead which gives them an intersection cross section larger than their own size.
Unlike Vipers, light and heavy missiles are a combination of guided and fire-and-forget technology. Each missile contains a long range laser receiver that allows it to be controlled from its firing vessel or any other platform with the proper access codes. When the missile gets withing close range of its target an on board computer uses the missile's own sensor package to guide it to its target. A self-destruct charge allows the remote operator to destroy the missile at need.
Modified heavy missiles can be used to control other missiles in its flight allowing one laser guidance transmitter to control a barrage of missiles.
There are versions of both light and heavy missiles which have been converted into surveillance drones, ECM drones and even delivery systems for smart bombs, glide bombs and deadfall ordnance.
There are a variety of different sensor packages that can be used for guidance. Passive systems include radscanners, which can be used for Anti-Radiation Missile Homing (ARM), ladar homing, and neutrino homing,  and  PESA, good for Infrared imaging, Radar homing, and even optical homing. Multiscanners can be used to target particular targets based on human occupation or even to avoid them, as well as working in radscanner mode as above. In chemscanner mode particular ship locations or economic targets can be chosen. Gravscanner homers can lock onto force fields or the Barnes Manifold of a B/G engine.
For the cost in weight of a laser transceiver a missile can send telemetry data back to its mother ship. This slightly reduces its payload.
Because they can be remotely controlled missiles can be seeded in a location and be activated later. A missile's engine can also be turned off to allow it to drift further extending its range, though ballistic missiles are easy targets for lasers or railguns.