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The Krantivrtta is an instrument that is meant to measure the Celestial Latitude and Celestial Longitude of an object in the sky.

Krantivrtta consists of two brass circles of equal diameter pivoted together at one point on their circumference, maintaining an angle of 23.5 degrees between them.

The inner brass circle is always parallel to the equator of the Earth. By rotating the entire instrument around the polar axis, the outer brass ring is made parallel to the ecliptic at any given moment.

There is a sighting bar that is pivoted to the ecliptic ring, which, in this position, can be rotated around the ecliptic pole. The sighting bar is rotated, and is bought into the nearest alignment with the celestial object. The reading on the ecliptic ring, where the sighting bar rests, gives the Ecliptic Longitude of the object.

There is a quadrant attached to the sighting bar. There is a smaller sighting bar with this quadrant, which when aligned exactly towards the celestial object, allows one to read off the celestial latitude of this object on the quadrant scale.

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Page last modified on September 26, 2008, at 10:22 PM EST