Surrey Satellite Technology Ltd, or SSTL, is a spin-off company of the University of Surrey, now (July 2012) fully owned by EADS Astrium, that builds and operates small satellites.
Its satellites began as amateur radio satellites known by the UoSAT (University of Surrey SATELLITE) name, or by an OSCAR (Orbital Satellite Carrying Amateur Radio) designation. SSTL cooperates with the University's Surrey Space Centre, which does research into satellite and space topics.

SSTL has moved into remote sensing services with the launch of the Disaster Monitoring Constellation (DMC) and an associated child company, DMC International Imaging. SSTL also adopted the Internet Protocol for the DMC satellites it builds and operates, migrating from use of the AX.25 protocol popular in amateur radio. The CLEO Cisco router in Low Earth Orbit, on board the UK-DMC satellite along with a network of payloads, takes advantage of this adoption of the Internet Protocol. The UK-DMC satellite also carries a payload investigating GPS reflectometry.

RapidEye AG was a German geospatial information provider focused on assisting in management decision-making through services based on their own Earth observation imagery. The company owns a five satellite constellation producing 5 meter resolution imagery that was designed and implemented by MacDonald Dettwiler (MDA) of Richmond, Canada. Originally located in Munich, the company relocated 60 km southwest of Berlin to Brandenburg an der Havel in 2004.

Applications
RapidEye provides geospatial information-based management solutions to the following industries: agriculture, forestry, environment, spatial solutions.

Satellites
Five Identical Satellites: Built by Surrey Satellite Technology Ltd. (SSTL) of Guildford, subcontracted by MacDonald Dettwiler (MDA). Each satellite is based on an evolution of the flight-proven SSTL-100 bus, and measures less than one cubic meter and weighs 150 kg (bus + payload).

On November 6, 2013 RapidEye has officially changed its name to BlackBridge.

Spot Image is a French public limited company created in 1982 by the French Space Agency, Centre National d'Etudes Spatiales (CNES), the IGN, and Space Manufacturers (Matra, Alcatel, SSC, etc.). It is now (year 2012) a subsidiary of EADS Astrium (99%).

The company is the commercial operator for the SPOT Earth observation satellites.

Spot Image is a worldwide distributor of products and services using imagery from Earth observation satellites and works through a network of subsidiaries, local offices (Australia, Brazil, China, United States, Japan, Peru, Singapore), and partners. The goal is to provide on-the-spot service with worldwide availability.
Spot Image works with a network of more than 30 direct receiving stations handling images acquired by the SPOT satellites.

Satellite Imaging Corporation (SIC) is the official Value Added Reseller (VAR) of imaging and geospatial data products for:

• GeoEye
• RapidEye
• SPOT Image

IKONOS is a commercial earth observation satellite, and was the first to collect publicly available high-resolution imagery at 1-meter and 4-meter resolution. It offers multispectral (MS) and panchromatic (PAN) imagery.

IKONOS imagery began being sold on January 1, 2000. 

It derived its name from the Greek term eikōn for image.

It is operated by GeoEye.

GeoEye Inc. (formerly Orbital Imaging Corporation or ORBIMAGE) is a commercial satellite imagery company based in Herndon, Virginia, USA.

GeoEye operates its own fleet of Earth observation satellites, which provide visible and near-infrared images of land and sea at resolutions below 1 m.

GeoEye provides 253,000,000 square kilometres of satellite map images to Microsoft and Yahoo! search engines. Google has exclusive online mapping use of the new GeoEye-1 satellite. It is a major supplier to the USA National Geospatial-Intelligence Agency.

GeoEye's headquarters are in Herndon, Virginia. Satellite Operations are conducted in Herndon, Virginia and in Thornton, Colorado. The location in Saint Louis, Missouri provides additional image processing. There are multiple ground stations located worldwide.
GeoEye's primary competitors are DigitalGlobe and Spot Image.

The company was founded in 1992 as a division of Orbital Sciences Corporation in the wake of the 1992 Land Remote Sensing Policy Act which permitted private companies to enter the satellite imaging business. The division was spun off in 1997. It changed its name to GeoEye in 2006 after acquiring Denver, Colorado-based Space Imaging. Space Imaging was founded and controlled by Raytheon and Lockheed Martin. Its principal asset was the IKONOS satellite.

IRS-P3 is an Indian experimental Earth Observation mission, considered to be pre-operational and serving in parallel for technology evaluation and scientific methodology studies.

It was launched by PSLV-D3 on March 21, 1996 from SHAR Centre, Sriharikota, India. IRS-P3 carries two remote sensing payloads - Wide Field Sensor (WiFS) similar to that of IRS-1C, with an additional Short Wave Infrared Band (SWIR) and a Modular Opto-electronic Scanner (MOS). It also carries an X-ray astronomy payload and a C-band transponder for radar calibration. 

Mission completed during January 2006 after serving 9 years and 10 months. 

The X-ray Astronomy Experiment (IXAE) is a payload which was launched aboard the Indian Remote Sensing Satellite-P3 (IRS-P3) using a Polar Satellite Launch Vehicle (PSLV) on 1996 March 21.

(see article IXAE observations of the X-ray pulsar XTE J1946+274 )

The Polar Satellite Launch Vehicle, commonly known by its abbreviation PSLV, is an expendable launch system developed and operated by the Indian Space Research Organisation (ISRO). It was developed to allow India to launch its Indian Remote Sensing (IRS) satellites into Sun synchronous orbits, a service that was, until the advent of the PSLV, commercially viable only from Russia. PSLV can also launch small size satellites into geostationary transfer orbit (GTO). The PSLV has launched 52 satellites (26 Indian satellites and 26 foreign satellites) into a variety of orbits to date (May 2012).

Astrosat is India's first dedicated astronomy satellite and is scheduled to launch on board the PSLV in 2012. After the success of the satellite-borne Indian X-ray Astronomy Experiment (IXAE), which was launched in 1996, the Indian Space Research Organization (ISRO) has approved further development for a full fledged astronomy satellite - Astrosat.
A large number of leading astronomy research institutions in India and abroad are jointly building various instruments for the satellite. Important areas requiring broad band coverage include studies of astrophysical objects ranging from the nearby solar system objects to distant stars, to objects at cosmological distances; timing studies of variables ranging from pulsations of the hot white dwarfs to active galactic nuclei (AGN) with time scales ranging from milliseconds to few hours to days.
Astrosat is currently proposed as a multi-wavelength astronomy mission on an IRS-class satellite into a near-Earth, equatorial orbit by the PSLV. The 5 instruments on-board cover the visible (320-530 nm), near UV(180-300 nm), far UV(130-180 nm), soft X-ray (0.3-8 keV and 2-10 keV) and hard X-ray (3-80 keV and 10-150 keV) regions of the electromagnetic spectrum.

Mission
Astrosat will be a proposal-driven general purpose observatory, with main scientific focus on:

• Simultaneous multi-wavelength monitoring of intensity variations in a broad range of cosmic sources
• Monitoring the X-ray sky for new transients
• Sky surveys in the hard X-ray and UV bands
• Broadband spectroscopic studies of X-ray binaries, AGN, SNRs, clusters of galaxies and stellar coronae
• Studies of periodic and non-periodic variability of X-ray sources