The Langston Field is a fictional device featured in the CoDominium series of science-fiction novels.

The Langston Field generator creates a shield around a spacecraft which absorbs energy. Since the shield absorbs all wavelengths of light, it is completely black in normal use, like a black hole. It is necessary to raise sensors through the Field to see anything, much like a periscope. These sensors can be destroyed if they are outside the Field, so there are usually many backups on a warship. As the Field absorbs energy it starts to reradiate it and to glow as a perfect blackbody; the colour of the Field moves from infrared to red and through the visible spectrum to violet as the amount of reradiated energy increases. After a certain point, the Field generator can no longer absorb further energy: the Field collapses and the stored energy is released outwards and inwards; this latter usually destroys the ship.

Expanding Langston Field

The Moties did not realise that the Langston Field was possible until humans demonstrated it. The Moties were inconceivably superior to Humanity in the development of existing technologies, but lacked the ability (or perhaps the inclination) to carry out primary research. Even if they had had the ability, however, it is possible that they would never have developed Langston Field technology; even for Humanity it was a purely accidental discovery. Once the Motie Engineers saw that the Field was possible, they immediately devised an improvement to it: the Fields on Motie spaceships expand as they absorb energy. This gives the Field more surface area to disperse the energy again, and allows it to survive much longer.

The Moties' improvement is not useful for the human blockade ships that guard the original entrance to Mote System, because the entrance is inside the photospere of a red giant star. Their Fields would keep expanding, and the resulting greater surface area would cause them to absorb more heat instead of bleed it off. Motie ships generally used the expanding Langston Field, so when they attempted to run the blockade they heated up more quickly and were destroyed sooner.