Feet to Light-minutes (ft to lmin)

1 foot equals 1.694505604×10⁻¹¹ light-minutes (rounded).

1 foot = 1.694505604×10⁻¹¹ light-minutes

How to convert feet to light-minutes

To convert feet to light-minutes, multiply the number of feet by 1.694505604×10⁻¹¹. The factor is rounded to 10 significant digits. To go the other way, multiply light-minutes by 59,014,263,386 (rounded).

light-minutes = feet × 1.694505604×10⁻¹¹

Example: 10 feet = 1.694505604×10⁻¹⁰ light-minutes.

About these units

Foot (ft)

US & ImperialCurrent unit

12 inches. Defined as exactly 0.3048 meters. Still the standard unit for height, altitude in aviation and room dimensions in the US and UK.

Human anatomy supplied the idea: an adult foot is roughly 15 percent of body height. Ancient cultures turned that into standards, but not the same one. The Greek pous was about 302 mm, the standard Roman pes about 295.7 mm, and a Harappan foot of about 335 mm has been reported from the Indus Valley. Historically, a foot fell somewhere between about 250 and 335 mm. Charlemagne tried to standardize units around 790 with little lasting success, and in 1593 English law fixed the statute mile at 5,280 feet.

The modern foot dates from the 1959 International Yard and Pound Agreement, which defined the yard as exactly 0.9144 meter and so the foot as exactly 0.3048 meter; the UK adopted it on 1 January 1964. The US survey foot, defined in 1893 as 1200/3937 meter, was deprecated on 31 December 2022. Feet remain in everyday use for height and rooms in the US, and ISO shipping containers are defined in them. Aviation altitudes use them too: flight level 330 means 33,000 feet.

1 foot = 0.3048 meters (exactly).

Sources: Wikipedia: Foot (unit); Wikipedia: Mile; NIST Guide to the SI, Appendix B.8: conversion factors

Light-minute (lmin)

AstronomicalCurrent unit

The distance light travels in a minute (about 18 million km). The Sun is roughly 8.3 light-minutes from Earth.

Sunlight takes about 8.3 minutes to reach Earth, so the light-minute is the natural scale for the inner solar system. Its figure is exactly 60 light-seconds, which comes to 17,987,547,480 meters or about 18 million kilometers. The unit has no formal standing in the SI and no single inventor. It simply follows from the fixed speed of light, and it turns up in popular astronomy, in discussions of signal delays and in tables that give planetary distances as travel times.

Distance and delay are the same number in this unit, which makes it handy for spacecraft work. A signal to a distant spacecraft therefore cannot be answered instantly, because every light-minute of separation adds a minute each way. One astronomical unit is about 8.317 light-minutes, and Saturn's orbit at its closest approach to the Sun lies near 1.25 light-hours. Larger distances usually move up to light-hours or light-years.

1 light-minute = 17,987,547,480 meters (exactly).

Sources: Wikipedia: Light-minute; Wikipedia: Light-second

Related conversions

See all length units.