Space Surveillance and Tracking

ADS built for INAF-OAS Bologna the Tandem instrument installed on the G.D. Cassini telescope at Loiano observatory. Tandem was conceived and designed by professor Alberto  Buzzoni

Tandem is made by four f/3 Newtonian telescopes:

Depth Mode: all four telescopes converge on the same 2° x 2° FOV

Limiting magnitude:

V 19.2 in 120 sec exposure (data reduction process enabled) 

V 20.8 in 30 minutes (data reduction process enabled).

Wide-Field (mosaic) Mode: telescopes independently steered to cover adjacent fields

Limiting magnitude:

V 18.5 in 120 sec exposure

V 20 in 30 minutes

Tandem's astrometric accuracy of approximately 0.2 arcsec has been proved through observations of Near-Earth Asteroids (NEAs), Gaia-DR2 catalogue.

Wide Field Mode.
Andromeda Galaxy M31 displayed together with a full moon sketch as a reference.

COSMOS 2333 - TANDEM demonstrated its ability to track objects in LEO by arranging its four fields of view along the object's trajectory.
This technique allowed for astrometry of a 20° orbital arc in just 30-40 sec of observation time.

CLUSTER 2 - The system successfully recovered this satellite about a week before its atmospheric re-entry, using a 4-day-old TLE (latest available). This observation showcases TANDEM's ability to track objects with rapidly changing orbits. 

STEERABLE TELESCOPE CLUSTER (STC)

The main feature of our multiple telescope system is that each telescope can be oriented in two angular directions independently of the others, on a common equatorial mount. Thus the array can be used at its maximum depth in magnitude by converging the four telescopes on the same 2°x2°  FOV or, alternatively, fully exploiting the wider angular coverage on the sky by orienting each telescope to obtain a mosaic of four adjacent fields, covering a 16 deg2 FOV.  Notably, the user can freely arrange the mosaic, for example making a 2°x8° rectangular field, and orient it in the sky maximizing the object pass coverage.