Convert Light Year (ly) to Ken (ken) instantly.
About these units
Light Year (ly)
A light year is the distance that light travels in a vacuum in one Julian year, equal to approximately 9.4607 × 10¹⁵ meters. Despite its name, it is a unit of distance, not time. The light year arose from the need to express vast astronomical separations using a concept familiar to laypeople: the finite speed of light. By linking distance to time, it becomes easier to comprehend that observing distant stars is also an act of looking back in time. The light year is especially useful when describing the locations of nearby stars, nebulae, and star-forming regions. For example, Proxima Centauri lies roughly 4.24 light years away. Because light moves at about 300,000 km/s, even the nearest galactic objects are many trillions of kilometers distant, making ordinary units impractical. One of the light year's greatest strengths is how vividly it illustrates the immensity of space. When astronomers say a galaxy is millions of light years away, they convey not only a vast spatial separation but also the staggering temporal depth of the universe. The light year therefore plays a dual role as both a scientific measurement and an educational tool that grounds cosmic distances in a memorable framework.
Ken (ken)
The ken is a traditional Japanese unit of length, typically about 1.8 meters, though historically it ranged from 1.6 to 1.9 meters depending on the era and region. The ken is deeply tied to traditional Japanese architecture, especially temple and shrine construction. In classic building design, the ken measured the spacing between pillars in wooden structures. Because Japanese architecture emphasizes modularity and harmonious proportions, the ken allowed builders to create spaces that were both structurally efficient and aesthetically consistent. Many tatami room layouts are also derived from ken-based proportions. Beyond architecture, the ken carried symbolic importance in religious and cultural contexts. Temples were often laid out using ken multiples, reinforcing a sense of order, symmetry, and sacred geometry. Even though modern Japan uses the metric system, the ken persists in the restoration and preservation of historical buildings.