WhatTheStar

Constellations · Constellation · Octantis · Oct

Constellation

Octans

The octant — the navigator’s instrument — and the home of the south celestial pole, which has no bright star to mark it.

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Genitive
Octantis
Area
291 square degrees · 50th of 88
Brightest star
· magnitude 3.73
Naked-eye stars
60 brighter than magnitude 6.5
Highest at midnight
mid July

Did you know

The southern pole star, Polaris Australis, is barely visible to the naked eye — only about magnitude 5.4. Southern navigators use the Southern Cross instead.

History

Lacaille chose the octant, invented in the 1730s, because it had just revolutionised navigation. Octans never sets from New Zealand or southern Australia.

Words used here

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