Convert Arc second to Milliradian

Simple, fast and user-friendly online tool to convert Arc second to Milliradian ( arcsec to mrad ) vice-versa and other Angle related units. Learn and share how to convert Arc second to Milliradian ( arcsec to mrad ). Click to expand short unit definition.

Please select a valid country.
Clear input
   Arc second (arcsec) =    Milliradian (mrad)

What is Arc second ?

An Arcsecond (also written as arc second or abbreviated as ) is a very small unit of angle measurement used in fields like astronomy, navigation, and geodesy (the study of Earth's shape). It helps measure extremely tiny angles, especially when observing distant objects like stars or when needing high precision in mapping.

Understanding an Arcsecond

To understand what an arcsecond is, we need to start with the concept of a degree:

  • A degree (°) is a way of measuring angles, where a full circle is 360 degrees.
  • Each degree is further divided into 60 minutes (not to be confused with time minutes). These are called arcminutes.
  • Each arcminute is then divided into 60 arcseconds.

So, an arcsecond is 1/60th of an arcminute and 1/3600th of a degree.

Key Facts About Arcseconds
  • Tiny Angle:
    • Since an arcsecond is such a small angle, it's used for very precise measurements. For instance, 1 arcsecond is equal to 1/3600th of a degree.
  • Relation to Degrees:
    • 1 arcsecond = 1/3600th of a degree.
    • 1 arcminute = 60 arcseconds.
  • Practical Uses:
    • Astronomy: Astronomers use arcseconds to measure the positions and sizes of stars, planets, and other celestial objects in the sky. For example, the apparent size of a distant star might be just a few arcseconds across.
    • Geodesy: When mapping the Earth, precise locations might be given in degrees, minutes, and seconds to ensure accuracy.
Visualizing an Arcsecond

Visualizing an arcsecond can be challenging because it’s so small. Here's a way to think about it:

  • Imagine you’re looking at a clock face from a distance of 1 kilometer (0.6 miles). The angle that the width of a coin held at arm’s length would cover from that distance is roughly 1 arcsecond.

Another way to understand it:

  • If you divided a full circle (360°) into 1.3 million equal parts, each part would be about 1 arcsecond.
Practical Example

In astronomy, if you were observing the sky, the distance between two stars that are very close together might be just a few arcseconds. If a telescope can resolve details down to 1 arcsecond, it can distinguish two stars that are this close to each other.

Summary
  • An arcsecond is a very small unit of angle measurement, equal to 1/3600th of a degree.
  • It’s used in fields requiring precise angular measurements, like astronomy and geodesy.
  • There are 60 arcseconds in an arcminute and 3600 arcseconds in a degree.
  • Arcseconds help measure extremely tiny angles, making them essential for observing distant objects or mapping locations with high precision.

Understanding arcseconds is crucial for working in fields that involve very precise measurements of angles, especially when dealing with objects that are far away or when exact positioning is needed.




What is Milliradian ?

A Milliradian, often abbreviated as mrad or simply mil, is a unit of angle measurement that is commonly used in fields like ballistics, optics, and surveying. It’s a smaller subdivision of the radian, which is the standard unit for measuring angles in mathematics and engineering.

Understanding a Milliradian

To grasp what a milliradian is, let's first briefly review what a radian is:

  • A radian measures an angle by comparing the length of an arc (a part of a circle’s edge) to the radius of the circle. When the arc length equals the radius, the angle formed is 1 radian.

Now, a milliradian is simply one-thousandth (1/1000) of a radian. This small unit allows for very precise measurements of angles.

Key Facts About Milliradians
  • Relation to Radians:

    • Since 1 milliradian is 1/1000th of a radian, there are 1000 milliradians in a single radian.
    • Since there are 2π radians in a full circle, there are approximately 6283 milliradians in a full circle (2π × 1000 ≈ 6283).
  • Converting Milliradians to Degrees:

    • Since 1 radian equals approximately 57.3 degrees, 1 milliradian is about 0.0573 degrees (because 57.3°/1000 ≈ 0.0573°).
    • To convert milliradians to degrees, you multiply the number of milliradians by 0.0573.
  • Common Uses:

    • Ballistics and Shooting: In long-range shooting, milliradians are used to adjust scopes. For instance, if a scope is adjusted by 1 mil, it changes the point of impact by 1 meter at 1000 meters.
    • Surveying: Surveyors use milliradians for precise angular measurements over large distances.
    • Artillery and Military: Milliradians help calculate angles for targeting and positioning equipment.
Visualizing Milliradians

Imagine standing 1000 meters away from a target. If you shift your view by 1 milliradian, the target appears to move by 1 meter at that distance. This precision is why milliradians are so useful in activities requiring exact aiming and measurement over long distances.

Practical Example

In a rifle scope, if you see a target 1000 meters away, and you need to aim slightly higher to hit it due to gravity, you might adjust your scope by a few milliradians. Each milliradian adjustment moves the point of impact by 1 meter at that distance.

Summary
  • A milliradian is a unit of angle measurement that is 1/1000th of a radian.
  • It’s a very small angle, approximately equal to 0.0573 degrees.
  • Milliradians are widely used in fields requiring precise angular measurements, such as shooting, surveying, and military applications.
  • A full circle has about 6283 milliradians.

Understanding milliradians is essential for activities that require high precision in measuring small angles over long distances.



List of Angle conversion units
Degree Radian Milliradian Microradian Gradian Revolution Arc minute Arc second Milliarcsecond Microarcsecond