Feet to Light-hours (ft to lh)
1 foot equals 2.824176006×10⁻¹³ light-hours (rounded).
How to convert feet to light-hours
To convert feet to light-hours, multiply the number of feet by 2.824176006×10⁻¹³. The factor is rounded to 10 significant digits. To go the other way, multiply light-hours by 3,540,855,803,150 (rounded).
light-hours = feet × 2.824176006×10⁻¹³
Example: 10 feet = 2.824176006×10⁻¹² light-hours.
About these units
Foot (ft)
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-hour (lh)
The distance light travels in an hour (about 1.08 billion km). Pluto is about 4.8 light-hours from the Sun.
Reaching the outer planets takes light hours rather than minutes, and the light-hour is the matching unit. Equal to 3,600 light-seconds, it is exactly 1,079,252,848,800 meters, or about 1.08 billion kilometers. Like the other light-time units it is informal, defined entirely by the fixed speed of light and the length of the SI second rather than by any standards body, and it appears mainly in astronomy outreach and in descriptions of deep-space missions.
Neptune orbits at about 30 astronomical units, which with light taking roughly 499 seconds per unit works out to somewhat over four light-hours. Pluto, at an average of 34.72 astronomical units, is about 4.81 light-hours from the Sun. The Voyager 1 probe passed 23 light-hours from Earth and the Sun by 2025 and is expected to reach one light-day, 24 light-hours, around late 2026. Beyond that scale the light-day, light-week and light-year take over.
1 light-hour = 1,079,252,848,800 meters (exactly).
Sources: Wikipedia: Light-hour; Wikipedia: Light-minute; Wikipedia: Astronomical unit
Related conversions
- Light-hours to feet (reverse)
- Feet to meters
- Feet to kilometers
- Feet to centimeters
- Feet to millimeters
- Feet to inches
- Feet to yards
- Feet to miles
- Feet to micrometers
- Feet to nanometers
- Feet to nautical miles
- Feet to pixels (CSS)
- Feet to light-years
- Meters to light-hours
- Kilometers to light-hours
- Centimeters to light-hours
- Millimeters to light-hours
- Inches to light-hours
- Yards to light-hours
- Miles to light-hours
See all length units.