Description
Celestaire Astra III Professional Commercial Edition – Whole Horizon Mirror is the top model in the Astra series and designed for professional use, teaching and intensive training in astronomical navigation. Combining high precision, robust construction and good ergonomics, this sextant is an advanced instrument for serious sextant 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 III Professional is a further development of the well-known Astra IIIB, which is one of the world’s most widely used metal sextants. The Professional model features a precise bronze arc fused to a lightweight aluminum frame. Bronze can be produced with a higher tolerance than aluminum, giving better scale precision, while the aluminum frame keeps the weight low and the instrument comfortable to use over time.
The extra weight in the bronze arc also gives the sextant excellent balance and stability during observations. At the same time, the model has an improved and more ergonomic handle for better comfort during longer observations.
The sextant is supplied here with a Whole Horizon Mirror, where the entire horizon mirror reflects the horizon. This solution makes it easier to learn the technique and is particularly suitable for astro-navigation courses and for navigators who want a clear and easily visible horizon during observations.
The instrument is equipped with LED illumination of the arc and micrometer drum, powered by two AA batteries in the handle. This makes it possible to read the instrument when observing at dusk or night, for example when observing stars.
The mirrors are carefully tested for high optical quality and the sextant is designed so that the horizon mirror can be easily switched between split and whole-horizon type using two screws. This makes the instrument flexible for different preferences and applications.
Celestaire Astra III Professional has a documented precision of ±15 arc seconds throughout the arc, making it suitable for both teaching and professional navigation. The model has also been selected by NASA for testing on the International Space Station (ISS) as part of astronomical navigation research.
The sextant is delivered in a sturdy lacquered wooden box and includes telescope, solar filters, certificate of accuracy, instruction book and adjustment tools.
This is an advanced instrument for sextant navigation at sea, used by long-distance sailors, navigation enthusiasts and maritime institutions.
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.
