Finmeccanica sensor part of the New Horizons mission to study Pluto

Finmeccanica sensor part of the New Horizons mission to study Pluto

Thanks to the A-STR (Autonomous Star Tracker), a star sensor produced by Finmeccanica - Selex ES, Italian technology is voyaging to the edges of the solar system, passing 12,500 km from Pluto. Called "Star Camera" by NASA, the on-board star tracker has guided the NASA New Horizons mission probe as far as Pluto. The lone Italian contribution to the US mission to study Pluto, the A-STR for New Horizons allows the probe to orient itself in space so as to transmit its data back to earth.


Produced at the Selex ES Campi Bisenzio facility, the A-STR was installed in the NASA probe in 2004. The version used in this mission is composed of a dual sensor which allows the instrument to operate both during rotational phases of the probe (rotating around its own axis during the cruise phase), and when the probe is stably pointed towards the planet. The Italian star tracker communicates the vehicle's attitude to the on-board computer via on-board software, allowing it to correctly point its instrumentation towards Pluto.

The basic hardware is similar to that used by the attitude sensor installed in the Rosetta probe for the Rosetta ESA mission.


Since 2001, Selex ES has produced and delivered over 100 star trackers around the world, and this figure is set to reach 200 units by the end of 2016. As a matter of fact, other units are currently in production, for example the ones which will guide the two "ExoMars" probes towards the red planet in 2016 and 2018 as part of the "ExoMars" European mission, being carried out in conjunction with the Russian space agency.

Rome 15/07/2015