COSMO-SkyMed flare
A COSMO-SkyMed flare above the UK
ManufacturerThales Alenia Space
Country of originItaly
ApplicationsEarth observation radar
Launch mass1,700 kg (3,700 lb)[1]
Power4 kW
RegimeSun-synchronous orbit
Design life5 years (planned)
On order4
Maiden launchCOSMO-1
23 June 2007, 02:34:00 UTC
Last launchCOSMO-4
5 November 2010, 02:20:03 UTC
COSMO-SkyMed Second Generation
ManufacturerThales Alenia Space
Country of originItaly
ApplicationsEarth observation radar
Launch mass2,205 kg (4,861 lb)[2]
Power5 kW
RegimeSun-synchronous orbit
Design life7 years (planned)
On order4
Maiden launchCSG-1
18 December 2019, 08:54 UTC

COSMO-SkyMed (COnstellation of small Satellites for the Mediterranean basin Observation) is an Earth-observation satellite space-based radar system funded by the Italian Ministry of Research and Ministry of Defence and conducted by the Italian Space Agency (ASI), intended for both military and civilian use.[3] The prime contractor for the spacecraft was Thales Alenia Space. COSMO SkyMed is a constellation of four dual use Intelligence, surveillance, target acquisition, and reconnaissance (ISR) Earth observation satellites with a synthetic-aperture radar (SAR) as main payload, the result of the intuition of Giorgio Perrotta in the early nineties. The synthetic-aperture radar was developed starting in the late nineties with the SAR 2000 program funded by ASI.

The space segment of the system includes four identical medium-sized 1,700 kg (3,700 lb) satellites called COSMO-SkyMed (or COSMO) 1, 2, 3, 4, equipped with synthetic-aperture radar (SAR) sensors with global coverage of the planet.[4] Observations of an area of interest can be repeated several times a day in all-weather conditions. The imagery is applied to defense and security assurance in Italy and other countries, seismic hazard analysis, environmental disaster monitoring, and agricultural mapping.[5]

COSMO-SkyMed first generation

The four satellites are in Sun-synchronous polar orbits with a 97.90° inclination at a nominal altitude of 619 km (385 mi) and an orbital period of 97.20 minutes. The local time ascending node at the equator is 06:00. The operating life of each satellite is estimated to be 5 years. Each satellite repeats the same ground track every 16 days. They cross the equator at approximately 06:00 and 18:00 local-time each day and can image any point twice each day. The satellites are phased in the same orbital plane, with COSMO-SkyMed's 1, 3, and 2 at 90° intervals followed by COSMO-SkyMed 4 at 67.5° after COSMO-SkyMed 2. The offset of satellite 4 allows a one-day interferometry mode for elevation information.[6] The Sun-synchronous orbit (SSO) is used due to power (Electrical Power Subsystem) and revisit time requirements.

The satellites' main components are:

The radar antenna is a phased array that is 1.4 × 5.7 m (4 ft 7 in × 18 ft 8 in). The system is capable of both single- and dual-polarization collection. The center frequency is 9.6 GHz with a maximum radar bandwidth of 400 MHz.[7]

List of launches

United Launch Alliance provided launch services for the satellites with their Delta II 7420-10C launch vehicles from Vandenberg Air Force Base.[8] Satellite processing for the first two satellites was handled by the Astrotech Space Operations subsidiary of SPACEHAB.[5] The first satellite COSMO-1 (COSPAR 2007-023A) was launched at 02:34:00 UTC on 8 June 2007.[9] COSMO-2 (COSPAR 2007-059A) was launched at 02:31:42 UTC on 9 December 2007,[10] the launch having been delayed from 6 December 2007 due to bad weather, and problems with the rocket's cork insulation. COSMO-3 (COSPAR 2008-054A) launched at 02:28 UTC on 25 October 2008. COSMO-4 (COSPAR 2010-060A) launched on 6 November 2010, at 02:20 UTC.[11]

Flight No. Date/Time (UTC) Launch site Launch vehicle Payload Outcome
1 8 June 2007, 02:34:00 VAFB, SLC-2W Delta II 7420-10 COSMO-1 Success
2 9 December 2007, 02:31:42 VAFB, SLC-2W Delta II 7420-10 COSMO-2 Success
3 25 October 2008, 02:28:25 VAFB, SLC-2W Delta II 7420-10C COSMO-3 Success
4 6 November 2010, 02:20:03 VAFB, SLC-2W Delta II 7420-10C COSMO-4 Success

Ground segment

The ground segment of the system is composed of:

The governments of Argentina and France are involved respectively in the civil and military segments of the system.

SAR capabilities

The COSMO-SkyMed satellites have three basic types of imaging modes:

There are two Spotlight modes:

There are two Stripmap modes:

There are two ScanSAR modes:

The system is sized to collect up to 450 images per satellite per day.[12]


e-GEOS, S.p.A., a joint venture between European spaceflight services company Telespazio (80%) and the Italian Space Agency (ASI) (20%), has the exclusive worldwide commercial rights to sell COSMO-SkyMed data and products.[13][12]


The COSMO-SkyMed satellites are lesser-known deliverers of satellite flares, sometimes approaching magnitude −3. Flares come mainly from SAR-panels of the satellites. Although overshadowed by the Iridium satellites, the flares are often long-lasting, with the satellites traversing much of the sky at brighter-than-average magnitudes.

COSMO-SkyMed second generation (CSG)

To replace the first COSMO-SkyMed constellation, the Italian Space Agency is developing the COSMO-SkyMed second generation constellation. The 2nd generation constellation has the same function of radar-based Earth observation with particular focus on the Mediterranean area as the 1st generation. Like the 1st generation, the 2nd generation also consists of 4 satellites, CSG-1, CSG-2, CSG-3 and CSG-4. The satellites are improved versions of the first generation satellites. Also the radar payload CSG-SAR (COSMO-SkyMed Second Generation Synthetic Aperture Radar) is an improved version of the first generation X-band SAR payload. Furthermore, the 2nd generation satellites will operate in the same orbit (indeed, in the same orbital plane) as the first generation satellites. The 2nd generation satellites slightly outweigh the first generation satellites at 2,205 kg (4,861 lb) of mass.[14]

The contract for building two satellites was signed in September 2015. In December 2020, another two satellites were ordered. The satellites are built by Thales Alenia Space (the successor company of Alenia Spazio). They have a planned lifetime of 7 years. CSG-1 was launched on 18 December 2019 by Soyuz ST-A from Centre spatial Guyanais (CSG). CSG-2 was launched on 31 January 2022 by Falcon 9 Block 5 from Space Launch Complex 40 at Cape Canaveral Space Force Station,[15] while the CSG-3 satellite is scheduled to be launched in 2024 on a Vega-C launch vehicle.[16]

List of launches

Flight No. Date/Time (UTC) Launch site Launch vehicle Payload Outcome Notes
1 18 December 2019, 08:54:20 Kourou, ELS Soyuz ST-A / Fregat-MT CSG-1 Success On 18 January 2021, COSMO-SkyMed Second Generation-1 (CSG-1) became operational with the first of four satellites.[17]
2 31 January 2022, 23:11:14 CCSFS, SLC-40 Falcon 9 Block 5
CSG-2 Success On 31 January 2022, SpaceX launched COSMO-SkyMed Second Generation FM2 mission to low Earth orbit from Space Launch Complex 40 (SLC-40) at Cape Canaveral Space Force Station in Florida.
3 2025 Kourou, ELV Vega-C CSG-3 Planned
4 2027 ? Kourou, ELV Vega-C CSG-4 Planned

See also


  1. ^ "COSMO-SkyMed (Constellation of 4 SAR Satellites)". Retrieved 26 November 2020.
  2. ^ "COSMO-SkyMed Second Generation (CSG) Constellation". Retrieved 26 November 2020.
  3. ^ "COSMO-SkyMed: Mission definition and main applications and products" (PDF). ESA.
  4. ^ "COSMO-SkyMed". Telespazio. Archived from the original on 8 July 2007.
  5. ^ a b "SPACEHAB Subsidiary Signs New Contracts Totaling US$4.7 million". SPACEHAB.
  6. ^ "COSMO-SkyMed Mission and Products Description 23/01/2019". Italian Space Agency. Retrieved 24 August 2020.
  7. ^ "COSMO-SkyMed User Guide" (PDF). ASI. Archived from the original (PDF) on 29 August 2017. Retrieved 8 November 2012.
  8. ^ "Boeing To Launch Fourth EO Satellite For Italy". SpaceDaily. 23 December 2008.
  9. ^ "Worldwide launch schedule". Spaceflight Now. Archived from the original on 11 September 2013.
  10. ^ NASA – Delta II launches with COSMO-SkyMed-2 Archived 8 December 2007 at the Wayback Machine
  11. ^ "COSMO 1, 2, 3, 4". Gunter's Space Page. 7 July 2020. Retrieved 12 October 2021.
  12. ^ a b "eGEOS: COSMO-SkyMed Overview". eGEOS. Archived from the original on 22 July 2013. Retrieved 10 August 2011.(subscription required)
  13. ^ "E-GEOS to Create Early Warning System for Caribbean Weather Emergencies". 18 December 2018. Retrieved 23 August 2019.
  14. ^ "CSG 1, 2, 3, 4 (COSMO-SkyMed 2nd Gen.)". Gunter's Space Page. 3 October 2021. Retrieved 12 October 2021.
  15. ^ "Falcon 9 finally launches with Italian CSG-2 Earth observation satellite". NASASpaceflight. 31 January 2022. Retrieved 1 February 2022.
  16. ^ "COSMO-SKYMED". Italian Space Agencydate. 3 October 2021. Retrieved 3 October 2021.
  17. ^ "COSMO-SkyMed". Agenzia Spaziale Italiana. 12 October 2021. Retrieved 12 October 2021.
  18. ^ "CSG-2 | Falcon 9 Block 5". 25 January 2022.