Stargazers hopeful to photograph the next arrival of Halley's Comet won't need to leave their fate to the heavens, thanks to a handy device that keeps the stars lined up like ducks in a row. The Nanotracker, a precision mini motor, is a boon for serious camera users that allows for precise, unblurred picture-taking of stars and planets at night.

Developed by Sightron, a maker of riflescopes and other hunting-related optical gear, the palm-sized unit turns the entire camera apparatus in line with the earth's rotation, making long-exposure shots possible.

The device operates fairly simply. The user bolts the unit between the tripod and the camera's base, after using a built-in keyhole to find the North Star. Just as it had been useful to maritime navigators, the North Star (aka Polaris) is used as reference point as it remains the brightest "fixed" point in space close to the North Pole.

The motor shifts the position of the camera incrementally by revolving in one full turn every 24 hours.

"Smartphone cameras have come a long way in recent years, but equipment like the Nanotracker is in a different league," says Takeyuki Fujii of Sightron Hong Kong. "If you're serious about taking pictures of the stars, it is assumed that you know what you're doing. The precision required for proper celestial tracking literally can't be left in human hands."

An on-board switch allows for either clockwise or counterclockwise motion, commensurate with either northern or southern hemisphere use. The Southern Cross constellation functions as a reference point for locations south of the equator.

Sightron makes two models of the Nanotracker. The single-speed AG version operates in four modes, and can carry an optical configuration of up to 2kg - appropriate for DSLR cameras. The heavier duty, six-speed TL unit is geared for video cameras, and enables time-lapse filming. It can handle gear up to 8kg in weight.

The hardware is made in Japan.

Both devices are driven by AA alkaline batteries or can be connected by USB mini plug. They can be found at Amazon.com for under $300, well below the price point of rival Vixen Polarie's Star Tracker. The Nanotracker's compact size and price are driving sales, and online reviews are largely positive.

Stargazers will have much to study before Halley's Comet is due to appear again in mid-2061!