COSMO-SkyMed


COSMO-SkyMed 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, intended for both military and civilian use. 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 Earth observation satellites with a synthetic-aperture radar 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 satellites called COSMO-SkyMed '1, 2', 3, 4, equipped with synthetic-aperture radar sensors with global coverage of the planet. 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.

COSMO-SkyMed first generation

The four satellites are in Sun-synchronous polar orbits with a 97.90° inclination at a nominal altitude of 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. The Sun-synchronous orbit is used due to power and revisit time requirements.
The satellites' main components are:
The radar antenna is a phased array that is. 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.

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. Satellite processing for the first two satellites was handled by the Astrotech Space Operations subsidiary of SPACEHAB. The first satellite COSMO-1 was launched at 02:34:00 UTC on 8 June 2007. COSMO-2 was launched at 02:31:42 UTC on 9 December 2007, the launch having been delayed from 6 December 2007 due to bad weather, and problems with the rocket's cork insulation. COSMO-3 launched at 02:28 UTC on 25 October 2008. COSMO-4 launched on 6 November 2010, at 02:20 UTC.
Flight No.Date/Time Launch siteLaunch vehiclePayloadOutcome
18 June 2007, 02:34:00VAFB, Vandenberg [Space Launch Complex 2|SLC-2W]Delta II 7420-10COSMO-1
29 December 2007, 02:31:42VAFB, SLC-2WDelta II 7420-10COSMO-2
325 October 2008, 02:28:25VAFB, SLC-2WDelta II 7420-10CCOSMO-3
46 November 2010, 02:20:03VAFB, SLC-2WDelta II 7420-10CCOSMO-4

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 is an improved version of the first generation X-band SAR payload. Furthermore, the 2nd generation satellites will operate in the same orbit as the first generation satellites. The 2nd generation satellites slightly outweigh the first generation satellites at of mass.
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. They have a planned lifetime of 7 years.

List of launches

CSG-1 was launched on 18 December 2019 by Soyuz ST-A from Centre spatial Guyanais. CSG-2 was launched on 31 January 2022 by Falcon 9 Block 5 from Space Launch Complex 40 at Cape Canaveral Space Force Station. CSG-3 was launched in January 2026 on a Falcon 9 Block 5 launch vehicle.
Flight No.Date/Time COSPAR IDLaunch siteLaunch vehiclePayloadOutcomeNotes
118 December 2019, 08:54:202019-092AKourou, ELSSoyuz ST-A / Fregat-MTCSG-1On 18 January 2021, COSMO-SkyMed Second Generation-1 became operational with the first of four satellites.
231 January 2022, 23:11:142022-008ACCSFS, SLC-40Falcon 9 Block 5
B1052.3
CSG-2On 31 January 2022, SpaceX launched COSMO-SkyMed Second Generation FM2 mission to low Earth orbit from Space Launch Complex 40 at Cape Canaveral Space Force Station in Florida.
33 January 2026, 02:09:162026-001AVandenberg, SLC4EFalcon 9 Block 5CSG-3First orbital launch of 2026
42027 ?Kourou, ELVVega-CCSG-4

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:
  • Spotlight, a high-resolution mode collected over a small area by steering the radar beam slightly fore-to-aft during the collection period
  • Stripmap, a medium-resolution mode collected over long, continuous swaths in which the beam is pointed broadside to the satellite track
  • ScanSAR, a low-resolution mode that creates extra-wide swaths by collecting short segments at different ranges and then mosaicking them together
There are two Spotlight modes:
  • SPOTLIGHT1, which is a military-only mode, and
  • SPOTLIGHT2, which provides a resolution of over a area. Spotlight polarization is limited to either HH or VV
There are two Stripmap modes:
  • HIMAGE, which provides a resolution of between over a swath of, and
  • PINGPONG, which collects dual-polarization data at resolution over a swath of. The dual-polarization data can consist of any two polarizations, and it is non-coherent, as it is collected in "pulse groups" that alternate from one polarization to the other.
There are two ScanSAR modes:
  • WIDEREGION, which provides resolution data over a swath of, and
  • HUGEREGION, which provides resolution data over a swath of.
The system is sized to collect up to 450 images per satellite per day.

Commercialization

e-GEOS, S.p.A., a joint venture between European spaceflight services company Telespazio and the Italian Space Agency, has the exclusive worldwide commercial rights to sell COSMO-SkyMed data and products.

Flares

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.