Description
The Celestaire Astra IIIB Deluxe Sextant – Split Horizon Mirror is a classic metal sextant that has been one of the world’s most widely used models for astronomical navigation since the 1980s. The model has been produced by Celestaire since 1986 and is known for combining good precision, robust construction and high optical quality at a relatively accessible price. Astra IIIB is used by long-distance sailors, navigation enthusiasts and sextant navigation courses, and is for many the entry-level model for serious astro-navigation.
A sextant is used to measure the angle between a celestial body – such as the sun, moon or a star – and the horizon. Together with nautical almanacs and tables, you can calculate your position at sea without using GPS. Even today, astronomical navigation is an essential skill for sailors who want an independent backup system to electronic navigation.
Astra IIIB has a lightweight and corrosion-resistant aluminum frame that provides good stability while keeping the weight low. This makes the sextant comfortable to use for long periods of time and makes it easier to keep the instrument stable during observations in waves and changing weather conditions. The good balance also makes the model particularly suitable for navigators who do not use a sextant on a daily basis.
The sextant is known to be one of the most user-friendly metal sextants on the market. The scale has clear white degree markings against a black background, which makes reading easier, even in low light conditions. The instrument is equipped with LED illumination of the arc and micrometer drum, powered by two standard AA batteries in the handle.
This version comes with Split Horizon Mirror, the traditional mirror solution used on most classic sextants. One half of the horizon mirror is reflective, while the other half is clear glass so that the horizon is seen directly through the mirror. Many experienced navigators prefer this solution because it provides a natural and precise image of the horizon during observations.
The mirrors and filter glasses are carefully tested during production to ensure high optical quality. The hexagon is also designed so that the horizon mirror can be easily switched between split and whole-horizon types using two screws. This makes it possible to customize the instrument if you later want a different mirror solution.
The Celestaire Astra IIIB Deluxe is delivered in a sturdy lacquered wooden box and includes a telescope, instruction manual, certificate of accuracy and alignment tools. The model comes with a 3.5×40 monocular telescope as standard.
Astra IIIB is a robust and precise instrument that is well suited for both training and practical sextant sailing, and is one of the most widely used sextant models in the world.
Production
Celestaire sextants are manufactured by Changzhou Celestaire Instrument Co. in China to Celestaire USA specifications and quality standards. Each sextant comes with a certificate of accuracy and in a protective lacquered wooden box with instruction manual and adjustment tools.
Navigasjonsbutikken Kart.no AS is a distributor of Celestaire in Norway. For schools, courses and institutions, we can also deliver larger batches of sextants – please contact us for price and delivery time.
