Star hopping

From Wikipedia, the free encyclopedia

Star hopping is a technique that is often used by amateur astronomers to locate items of interest in the night sky. It can be used in place of or in conjunction with Setting circles.

Most celestial objects of interest are not visible without instruments such as telescopes or binoculars. Yet from their nature telescopes and binoculars have a much smaller field of view than the unaided eye, and directing these instruments to exactly where intended may present difficulties.

Star hopping uses bright stars as a guide to finding fainter objects. The bright star can easily be seen through a telescope or binocular and with the unaided eye, and this allows the astronomer to establish exactly where they are looking with their instrument according to a map of the sky.

Knowing where the object is on the map, the astronomer can identify a trail of stars that will lead them from the starting location towards the item they are searching for in the sky. It then becomes possible to move the aim of the telescope by small increments, following the identified patterns of stars in the sky, perhaps referring back to the map on occasion. The observer may also follow the equatorial coordinate system on a star map in combination with telescopes equipped with equatorial mounts to "hop" or "slide" along the lines of right ascension or declination from a well known object to find a more obscure object. This can be assisted using setting circles.

[edit] External links

• An interactive guide to Star hopping
• Star hopping guide