Canopus (α Car / α Carinae / Alpha Carinae) is the brightest star in the southern constellation of Carina, and the second brightest star in the sky, with a visual magnitude of −0.62, second only to Sirius. Right ascension (RA; symbol α: Greek letter alpha) is the astronomical term for one of the two coordinates of a point on the celestial sphere when using the equatorial coordinate system. ... In astronomy declination (dec) is one of the two coordinates of the equatorial coordinate system, the other being either right ascension or hour angle. ... Alpha (uppercase Α, lowercase α) is the first letter of the Greek alphabet. ... Orion is a remarkable constellation, visible from most places on the globe (but not always the whole year long). ... Carina is the Latin word for keel. ... Bright stars can be bright because they produce more light, or because they are closer to us. ... The apparent magnitude (m) of a star, planet or other heavenly body is a measure of its apparent brightness; that is, the amount of light received from the object. ... The position of Sirius Sirius (α CMa / α Canis Majoris / Alpha Canis Majoris) is the brightest star in the nighttime sky, with a visual apparent magnitude of −1. ...

Canopus is a yellowish-white supergiant star. It is located well into the southern hemisphere, at a declination of −52° 42' (2000) and a right ascension of 06h24.0m, and is visible on the southern horizon of even the southern US States as far north as Virginia or Kentucky or the African coast of the Mediterranean Sea. A supergiant is a very large type of star which is ~10 to 50 solar masses on the Hertzsprung-Russell diagram. ... The Pleiades star cluster A star is any massive gaseous body in outer space. ... In astronomy declination (dec) is one of the two coordinates of the equatorial coordinate system, the other being either right ascension or hour angle. ... Right ascension (RA; symbol α: Greek letter alpha) is the astronomical term for one of the two coordinates of a point on the celestial sphere when using the equatorial coordinate system. ... State nickname: Old Dominion Other U.S. States Capital Richmond Largest city Virginia Beach Governor Mark R. Warner (D) Official languages English Area 110,862 km² (35th)  - Land 102,642 km²  - Water 8,220 km² (7. ... State nickname: Bluegrass State Other U.S. States Capital Frankfort Largest city Louisville Governor Ernie Fletcher (R) Official languages English Area 104,749 km² (37th)  - Land 102,989 km²  - Water 1,760 km² (1. ... A mediterranean sea, in oceanography, is a mostly enclosed sea that has limited exchange of deep water with outer oceans and where the water circulation is dominated by salinity and temperature differences rather than winds. ...

Canopus is, according to the Hipparcos satellite, 310 light years (96 parsecs) from our solar system (based on parallax measurement of 10.43 ± 0.53 mas). Before Hipparcos, distance estimates for the star varied very widely, up to as much as 1200 light years or as close ar 96 light years; had the former been correct Canopus would have been one of the most powerful stars in our galaxy. As is, it is still about 20,000 times brighter than the Sun and the most intrinsically bright star within 700 light years or so. It is much more luminous, intrinsically, than the sole star that appears brighter than it from Earth—Sirius is a mere 22 times more luminous than our sun, and depends on being much closer to us to beat its rival in apparent magnitude. In fact, for a large fraction of stars in the local stellar neighbourhood, Canopus is the "brightest star in the sky". The High Precision Parallax Collecting Satellite of the Hipparcos Space Astrometry Mission was a project of the European Space Agency (ESA) dedicated to the measurement of stellar parallax and the proper motions of stars. ... A light year, abbreviated ly, is the distance light travels in one year: roughly 9. ... The parsec (symbol pc) is a unit of length used in astronomy. ... Presentation of the Solar system (not to scale). ... Parallax (Greek: παραλλαγή (parallagé) = alteration) is the change of angular position of two stationary points relative to each other as seen by an observer, due to the motion of said observer. ... The Sun is the star at the centre of our Solar system. ... The position of Sirius Sirius (α CMa / α Canis Majoris / Alpha Canis Majoris) is the brightest star in the nighttime sky, with a visual apparent magnitude of −1. ... The apparent magnitude (m) of a star, planet or other heavenly body is a measure of its apparent brightness; that is, the amount of light received from the object. ...

The difficulty in measuring Canopus' distance stemmed from its unusual nature. The usual classification for Canopus is F0 IA, and F-class bright supergiants are rare and poorly understood; they may be stars in the process of evolving to or away from red giant status. This in turn made it difficult to guess how intrinsically bright it is and so how far away it might be. Direct measurement was the only way to solve the problem, and as it was too far away for earth-based parallax observations to be made, a precise distance had to wait until the Space Age. A supergiant is a very large type of star which is ~10 to 50 solar masses on the Hertzsprung-Russell diagram. ... According to the Hertzsprung-Russell diagram, a red giant is a large non-main sequence star of stellar classification K or M; so-named because of the reddish appearance of the cooler giants. Examples include Aldebaran and Arcturus. ...

The name "Canopus" has two common derivations, both listed in Richard Hinckley Allen's touchstone of stellar mythology, Star Names: Their Lore and Meaning; which is correct is a matter of conjecture. One comes from the legend of the Trojan War. As the constellation Carina is part of the now-obsolete, gigantic Argo Navis constellation, which represented the ship used by Jason and the Argonauts, the brightest star in the constellation was given the name of a ship's pilot from another Greek legend — Canopus was the pilot of Menelaus' ship on his quest to retrieve Helen of Troy after she was taken by Paris. The Trojan War was a war waged, according to legend, against the city of Troy in Asia Minor by the armies of the Acheans, following the kidnapping (or elopement) of Helen of Sparta by Paris of Troy. ... The constellation Argo Navis drawn by Johannes Hevelius in 1690 Argo Navis (or simply Argo) was a large southern constellation representing the Argo, the ship used by Jason and the Argonauts in Greek mythology. ... Jason (Greek: Ίασων) is a hero of Greek mythology. ... In Greek mythology, Canopus (or Canobus) was the pilot of the ship of King Menelaus of Sparta during the Trojan War. ... Menelaus (also transliterated as Meneláos), in Greek mythology, was a king of Sparta and son of Atreus and Aerope. ... Helen of Troy by Evelyn de Morgan Helen was the wife of Menelaus and reputed to be the most beautiful woman in the world, and her abduction by Paris brought about the Trojan War. ... The Eiffel Tower has become a symbol of Paris throughout the world. ...

The other etymology of the name is that it comes from the Egyptian Coptic Kahi Nub ("Golden Earth"), which refers to the way it would appear near the horizon in Egypt and be correspondingly reddened by atmospheric extinction from that position. There is also a ruined ancient Egyptian port, Canopus, apparently specifically named for the star, near the mouth of the Nile; its site was the location of the Battle of the Nile. The Coptic Language is the last phase of the Egyptian languages, and is the direct descendant of the ancient Egyptian language written in the hieroglyphic, hieratic, and demotic scripts. ... Canopus (also: Canobus) was an Ancient Egyptian coastal town, located in the Nile Delta. ... The Nile in Egypt Length 6 695 km Elevation of the source 1 134 m Average discharge 2 830 m³/s Area watershed 3 400 000 km² Origin  Africa Mouth  the Mediterranean Basin countries Uganda - Sudan - Egypt The Nile (Arabic: النيل an-nÄ«l), in Africa, is one of the two... The Battle of the Nile, also known as the Battle of Aboukir Bay, was an important naval battle of the French Revolutionary Wars between a British fleet commanded by Rear-Admiral Horatio Nelson and a French fleet under Vice-Admiral François-Paul Brueys DAigalliers. ...

Or it could be that Menelaus's legendary pilot was named after the port, and the port was named "Golden Floor" because of the many valuable cargoes that passed across its quays and the profits made by merchants there.

Due to its brightness and position away from the orbital plane of our solar system (the latter being in contrast to Sirius' position), Canopus is often used by American space probes for navigational purposes, using a special camera known as a "Canopus Star Tracker" in combination with a "Sun Tracker".