When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Milliradian - Wikipedia

    en.wikipedia.org/wiki/Milliradian

    Since an mrad is an angular measurement, the subtension covered by a given angle (angular distance or angular diameter) increases with viewing distance to the target. For instance the same angle of 0.1 mrad will subtend 10 mm at 100 meters, 20 mm at 200 meters, etc., or similarly 0.39 inches at 100 m, 0.78 inches at 200 m, etc.

  3. Light-second - Wikipedia

    en.wikipedia.org/wiki/Light-second

    The light-second is a unit of length useful in astronomy, telecommunications and relativistic physics.It is defined as the distance that light travels in free space in one second, and is equal to exactly 299 792 458 m (approximately 983 571 055 ft or 186 282 miles).

  4. Low Earth orbit - Wikipedia

    en.wikipedia.org/wiki/Low_Earth_orbit

    A wide variety of sources [5] [6] [7] define LEO in terms of altitude.The altitude of an object in an elliptic orbit can vary significantly along the orbit. Even for circular orbits, the altitude above ground can vary by as much as 30 km (19 mi) (especially for polar orbits) due to the oblateness of Earth's spheroid figure and local topography.

  5. Quarter mile - Wikipedia

    en.wikipedia.org/wiki/Quarter_mile

    Quarter-mile or 1 ⁄ 4 mile may refer to: . A dragstrip competition or vehicle test in motorsport, where cars or motorcycles compete for the shortest time from a standing start to the end of a straight 1 ⁄ 4 mile (0.40 km) track

  6. Visibility - Wikipedia

    en.wikipedia.org/wiki/Visibility

    a) the greatest distance at which a black object of suitable dimensions, situated near the ground, can be seen and recognized when observed against a bright background; b) the greatest distance at which lights of 1,000 candelas can be seen and identified against an unlit background.

  7. Distance measuring equipment - Wikipedia

    en.wikipedia.org/wiki/Distance_measuring_equipment

    In aviation, distance measuring equipment (DME) is a radio navigation technology that measures the slant range (distance) between an aircraft and a ground station by timing the propagation delay of radio signals in the frequency band between 960 and 1215 megahertz (MHz). Line-of-visibility between the aircraft and ground station is required.

  8. Green Rocks - Wikipedia

    en.wikipedia.org/wiki/Green_Rocks

    The Green Rocks) are a small cluster of rocks, 0.25 nautical miles (0.5 km) east of Honkala Island and an equal distance offshore, in the eastern part of the Swain Islands of Antarctica They were first mapped from air photos taken by U.S. Navy Operation Highjump , 1946–47, and are included in a 1957 survey of the Swain Islands by Wilkes ...

  9. Milestone - Wikipedia

    en.wikipedia.org/wiki/Milestone

    Old and new railway mileposts in the UK, indicating a distance of 33 + 1 ⁄ 4 miles (53.5 km) from the zero point. The Railways Clauses Consolidation Act 1845 [8] compels UK railway companies to provide their passengers with a means of determining the distance travelled (fares were set by distance at this time). Section 94 states: