Glossary term: Magnitude apparente
Description: La magnitude apparente est une mesure de la luminosité d'un corps céleste pour un observateur. Pour des raisons historiques, l'échelle de magnitude attribue des nombres plus élevés aux objets moins lumineux. La magnitude est une échelle logarithmique : une différence de cinq magnitudes correspondant à un facteur 100 dans la luminosité mesurée. Il existe de nombreuses échelles de magnitude, car la luminosité peut être mesurée à différentes longueurs d'onde et avec différentes techniques. L'échelle commune de "magnitude visuelle" est établie de telle sorte que l'étoile brillante Véga ait une magnitude apparente de zéro. Sur cette échelle, Sirius, l'étoile la plus brillante du ciel nocturne, a une magnitude de -1,46, et les magnitudes du Soleil et de la pleine Lune sont respectivement de -26,7 et -12,7. Les nombres négatifs indiquent que ces objets apparaissent plus brillants que Véga. Dans des conditions très sombres, les personnes ayant une excellente vision peuvent voir des étoiles jusqu'à une magnitude visuelle de 6. Le champ ultra-profond de Hubble atteint une magnitude visuelle proche de 31. C'est environ 10 milliards de fois plus faible que la magnitude 6.
Related Terms:
See this term in other languages
Term and definition status: The original definition of this term in English have been approved by a research astronomer and a teacher The translation of this term and its definition is still awaiting approval
The OAE Multilingual Glossary is a project of the IAU Office of Astronomy for Education (OAE) in collaboration with the IAU Office of Astronomy Outreach (OAO). The terms and definitions were chosen, written and reviewed by a collective effort from the OAE, the OAE Centers and Nodes, the OAE National Astronomy Education Coordinators (NAECs) and other volunteers. You can find a full list of credits here. All glossary terms and their definitions are released under a Creative Commons CC BY-4.0 license and should be credited to "IAU OAE".
If you notice a factual or translation error in this glossary term or definition then please get in touch.
Related Diagrams
Carte de la constellation d'Andromède
Credit: Adapté par le Bureau de l'astronomie pour l'éducation de l'AIU à partir de l'original de l'AIU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Crux Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope.
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Orion Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Libra Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Scorpius Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Sagittarius Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Carte de la constellation du Capricorne
Credit: Adapté par le Bureau de l'astronomie pour l'éducation de l'AIU à partir de l'original de l'AIU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Aquarius Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Pisces Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Aries Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Taurus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Gemini Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Cancer Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Leo Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Virgo Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Cetus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Ophiuchus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Octans Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Cassiopeia Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Ursa Minor Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Ursa Major Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Canis Major Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Antlia Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Apus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Aquila Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Ara Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Auriga Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Boötes Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Caelum Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Camelopardalis Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Canes Venatici Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Canis Minor Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Carina Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Centaurus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Cepheus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Chamaeleon Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Circinus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Columba Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Coma Berenices Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Corona Australis Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Corona Borealis Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Corvus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Crater Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Cygnus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Delphinus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Dorado Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Draco Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Equuleus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Eridanus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Fornax Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Grus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Hercules Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Horologium Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Hydra Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Hydrus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Indus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Lacerta Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Leo Minor Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Lepus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Lupus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Lynx Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Lyra Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Mensa Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Microscopium Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Monoceros Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Musca Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Norma Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Pavo Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Pegasus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Perseus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Phoenix Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Pictor Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Piscis Austrinus Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Puppis Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Pyxis Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Reticulum Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Sagitta Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Sculptor Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Scutum Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Serpens Caput Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Serpens Cauda Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Sextans Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Telescopium Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Triangulum Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Triangulum Australe Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Tucana Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Vela Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Volans Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons
Vulpecula Constellation Map
Credit: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
License: CC-BY-4.0 Creative Commons Attribution 4.0 International (CC BY 4.0) icons