Arcseconden

Arcseconden is a fictional unit of angular measurement used in speculative science fiction, fan-made glossaries, and world-building discussions. It is employed to express extremely small angular separations in a way that sits conceptually between familiar units such as arcseconds and microarcseconds. Unlike real-world angular units, arcseconden have no universally accepted definition or standard conversion, and their exact magnitude varies by source or author. Consequently, references to arcseconden should be interpreted within their specific fictional or hypothetical context rather than as established scientific terms.

In common fictional usage, arcseconden are described as a finer subdivision within an imagined angular system, allowing resolution or positioning details beyond what is described by arcseconds. Some authors treat arcseconden as a subdivision of an arcsecond, while others place them in an independent scale that requires fictional instruments or technologies to achieve such precision. The lack of standardization is typical for world-building terms and is often addressed by defining a conversion within a given work or glossary.

Etymology and usage: The name arcseconden blends the concept of an arc with the word second, evoking arcseconds in astronomy while signaling a nonstandard, fictional unit. It may appear in encyclopedic entries, gaming guides, or collaborative wikis to describe measurement capabilities, sensor precision, or angular resolution in imagined settings.

See also: arcsecond, microarcsecond, angular resolution, boresight.