arcsecond

USAGE SUMMARY

The phrase "arcsecond" is correct and usable in written English.
It is typically used in fields such as astronomy and optics to measure angles, specifically one-sixtieth of an arcminute. Example: "The telescope can resolve details as small as one arcsecond, allowing astronomers to observe distant celestial objects with great clarity."

✓ Grammatically correct

News & Media

Encyclopedias

Science

Human-verified examples from authoritative sources

Exact Expressions

2 human-written examples

This device measures sky brightness in units of magnitudes per square arcsecond (magnitude is a measure of brightness, the lower the number the brighter the sky; square arcseconds is a measure of area, where one arcsecond is 1/3600 of a degree).

The Guardian

In my back garden in the suburbs of Glasgow the SQM reads about 18 magnitudes per square arcsecond.

The Guardian

Human-verified similar examples from authoritative sources

Similar Expressions

4 human-written examples

The equinoxes drift westward along the ecliptic at the rate of 50.3 arcseconds annually as the celestial equator moves with Earth's precession.

Encyclopedia Britannica

Despite being in constant high-speed motion, it can lock on to a target celestial object and track it continuously without its gaze wandering by more than 0.007 "arcseconds" – the width of a human hair seen at a distance of 1.5km.

Independent

As Mr. Rees documents, the men lacked the benefit of roads, electricity or the digital precision allowed by satellite technology; as a result, on average, the markers are three arcseconds (i.e. 295 feet) north or south of the 49th parallel [2].

The New York Times

Feynman (1963, p. 697) gives an example that highlights this difference in magnitudes more dramatically by showing how the gravitational coupling between a proton and an electron in a hydrogen atom would shift the wave-function of an electron by just 43 arcseconds over a time period of 100 times the age of the Universe!

SEP

Expert writing Tips

Best practice

When describing extremely small angles in astronomy or optics, use "arcsecond" to provide a precise and universally understood measurement.

Common error

Avoid using "arcsecond" interchangeably with "arcminute" or "degree". Remember that 1 arcminute equals 60 arcseconds, and 1 degree equals 3600 arcseconds. Always specify the correct unit for the intended precision.

Linguistic Context

The term "arcsecond" functions as a unit of measurement, specifically for angles. It provides a precise way to quantify very small angles, particularly in fields like astronomy and optics. Ludwig indicates that this term is correctly used in contexts requiring accuracy in angular measurement.

Expression frequency: Rare

Frequent in

Science

40%

News & Media

30%

Encyclopedias

30%

Less common in

Formal & Business

0%

Social Media

0%

Wiki

0%

Ludwig's WRAP-UP

In summary, "arcsecond" is a unit of angular measurement equal to 1/3600th of a degree, primarily used in astronomy, optics, and surveying. As Ludwig AI confirms, the term is grammatically correct and serves to provide precise angular measurements in scientific and technical contexts. Although the term is not very common, it is important to use it correctly to not confuse it with "arcminute" or "degree". Alternatives include "second of arc" or "angular second". When writing about topics requiring very precise angles, "arcsecond" is the term you should use.

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

second of arc

Alternative term for the same unit of angular measurement.

angular second

Synonymous term emphasizing the angular nature of the measurement.

milliarcsecond

A smaller unit, equal to one-thousandth of an arcsecond.

minute of arc

A larger unit of angular measurement, equal to 60 arcseconds.

microarcsecond

An even smaller unit, equal to one-millionth of an arcsecond.

degree of arc

An even larger unit, equal to 60 arcminutes or 3600 arcseconds.

parallax second

Unit of length used to measure the vast distances to astronomical objects outside the Solar System.

angular resolution

The smallest angle that can be distinguished by a telescope or other optical instrument.

celestial sphere

An imaginary sphere of gigantic radius with the earth located at its center.

field of view

The extent of the observable world that is seen at any given moment.

FAQs

How is an arcsecond related to a degree?

An arcsecond is a very small unit of angular measurement. There are 60 arcseconds in an arcminute, and 60 arcminutes in a degree, meaning there are 3600 arcseconds in one degree.

What is the difference between an arcsecond and an arcminute?

An arcminute is a larger unit of angular measurement than an arcsecond. One arcminute is equal to 60 arcseconds. So, to express a very small angle, you'd use arcseconds; for a larger angle, you might use arcminutes.

In what fields is the term "arcsecond" typically used?

The term "arcsecond" is primarily used in astronomy, optics, and surveying to measure very small angles. It's crucial for precise measurements of celestial objects and in high-precision instrumentation.

Are there alternative terms for "arcsecond"?

Yes, "second of arc" and "angular second" are alternative terms that mean the same thing as "arcsecond". These terms are interchangeable.