Messierluettelo

Messierluettelo is the Finnish title for the Messier catalogue, a well‑known astronomical list of 110 deep‑sky objects assembled by French astronomer Charles Messier in the 18th century. The catalogue was originally published in 1771 and revised in 1781, then expanded by Messier’s assistant, Nicolas Louis de Lacaille, in 1801. The primary purpose of the catalogue was to aid comet hunters in distinguishing cometary appearances from permanent nebulous objects. Each entry in Messierluettelo is assigned a Messier number (from M1 to M110) and includes an abbreviation of the object's type, such as cluster, galaxy, or nebula, along with its location in the sky expressed in equatorial coordinates.

The Messier catalogue remains a staple of amateur astronomy, serving both as a practical observing guide and a historical record of early cataloguing efforts. It is widely used for educational programs, telescope course curricula, and public outreach. Messierluettelo provides a concise naming convention that has been adopted globally, with synonyms such as UGC, NGC, and IC used for many of its entries. The catalogue is available in printed handbooks and online databases, and it continues to be updated with additional photometric and spectroscopic data from modern surveys. Though it contains only 110 objects, Messierluettelo is valued for its orderly presentation, historical significance, and enduring relevance to the study of deep‑sky astronomy.