Constellations · Guide

Mic · Microscopii

Microscopium Constellation

Updated by Funfactorium Editorial1 min readFor fun · sources cited
Image: IAU and Sky & Telescope magazine (Roger Sinnott & Rick Fienberg) · CC-BY 3.0
In short

Microscopium (Mic) is one of the 88 constellations recognised by the International Astronomical Union. It covers 210 square degrees of the southern sky in quadrant SQ4. Its brightest star is Gamma Microscopii. The Latin genitive of the name is Microscopii, used to form star names within the constellation. The IAU standardised all constellation boundaries in 1930.

Quick facts

IAU name
Microscopium
Abbreviation
Mic
Latin genitive
Microscopii
Hemisphere
southern
Area
210 sq deg
Brightest star
Gamma Microscopii
Quadrant
SQ4
Family
Lacaille
Discovery era
Nicolas Louis de Lacaille, 1751-1752

Overview

Microscopium is one of the 88 constellations formally recognised by the International Astronomical Union (IAU). It occupies 210 square degrees of sky in the southern hemisphere sky, best visible at latitudes between +45 and -90 degrees in September. The constellation belongs to the Lacaille family of constellations. Its Latin genitive is Microscopii, the form used when naming stars within the constellation — for example, the brightest star Gamma Microscopii may appear in catalogues as Alpha Microscopii or similar. The IAU standardised the boundaries of all 88 constellations in 1930 under the direction of Eugène Delporte, using straight lines of right ascension and declination to eliminate the ambiguities of earlier variable-boundary systems.

Notable stars

The brightest star in Microscopium is Gamma Microscopii. Individual stars within Microscopium are conventionally named using Bayer designation — Greek letters followed by the Latin genitive of the constellation name (Microscopii) — introduced by Johann Bayer in his 1603 star atlas Uranometria. Flamsteed numbers (numeric designators followed by Microscopium) were added by John Flamsteed in his 1712 catalogue. Variable stars, double stars, and deep-sky objects within the Microscopium boundary are catalogued by the IAU with the abbreviation Mic.

History and catalogue

Microscopium was introduced or documented by Nicolas Louis de Lacaille, 1751-1752. The modern IAU constellation boundaries were formally established in 1930. The designation Mic is the official three-letter IAU abbreviation used in star catalogues, variable star designations, and positional references. The family classification 'Lacaille' groups this constellation with others sharing a region of sky or a common historical source in astronomical literature.

Sources & further reading (2)
  1. official-iau — accessed 2026-05-06
  2. encyclopedia — accessed 2026-05-06

Frequently asked questions

What does the name Microscopium mean?

Microscopium is the Latin name used by the IAU to designate this constellation. The name comes from classical Latin and Greek astronomical tradition. In star catalogues, stars within Microscopium are designated using the genitive form of the name (e.g. Alpha Microscopium or similar Latin genitive forms) — a naming convention introduced by Johann Bayer in his 1603 atlas Uranometria and still in use today.

How large is Microscopium compared to other constellations?

Microscopium covers 210 square degrees of sky. The full sphere of the sky contains 41,253 square degrees, so Microscopium occupies about 0.5% of the total sky. For comparison, the largest constellation is Hydra at 1303 square degrees; the smallest is Crux at 68 square degrees.

When and where is Microscopium visible?

Microscopium is primarily a southern hemisphere constellation. Observers at high northern latitudes cannot see it; it is best appreciated from the southern tropics or high southern latitudes. The brightest star, Gamma Microscopii, serves as the main visual anchor for locating the constellation. As with all constellations, the best viewing conditions are a dark sky away from artificial light pollution, with the constellation high enough above the horizon to minimise atmospheric absorption.

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