First two Galileo IOV satellites


The first orbital elements of Europe’s global satellite navigation system are in place. On 21 October 2011 a Soyuz rocket from French Guiana launched two satellites, with two more following on 12 October 2012: these four Galileo In-Orbit Validation (IOV) satellites currently in orbit represent the operational nucleus of the full 30-satellite constellation.

Fully representative of the others that will follow them into orbit, these first four IOV satellites will prove that the satellites and ground segment meet many of Galileo’s requirements and will validate the system’s design in advance of completing and launching the rest of the constellation.

Galileo IOV facts and figures

First launch: 21 October 2011
Second launch: 12 October 2012
Launch vehicle: Soyuz ST-B launcher with Fregat-MT upper stage
Launch site: Guiana Space Centre, French Guiana
Launch mass: 700 kg
Size (with solar wings stowed): 3.02 x 1.58 x 1.59 m
Size (with solar wings deployed): 2.74 x 14.5 x 1.59 m
Navigation payload: Two Passive Hydrogen Maser atomic clocks; two Rubidium atomic clocks; Clock monitoring and control unit; Navigation signal generator unit; L-band antenna for navigation signal transmission, C-band antenna for uplink signal detection, two S-band antennas for telemetry and telecommands; Search and rescue antenna
Available power: 1420 watts (sunlight) / 1355 watts (in eclipse)
Orbit: Medium-Earth orbit, 23 222 km
Orbital inclination: 56°
Operational lifetime: more than 12 years
Satellite control centre: CNES in Toulouse, France with the support of ESOC in Darmstadt, Germany for Launch and Early Operations Phase (LEOP), satellite control transferring to Oberpfaffenhofen Galileo Control Centre in Germany while Redu in Belgium performs the In-Orbit Test campaign
Navigation control centre: Fucino Galileo Control Centre in Italy

Last update: 7 December 2012

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