Pleiades (satellite)

Pleiades is a pair of Earth observation satellites from the Italian - French satellite program Orfeo. They are the optical component of the imaginary for both the civilian and for military use Orfeo system and smaller, less expensive and more mobile than their predecessors from the SPOT satellite series.

1A and 1B Pléiades Pléiades be operated at a distance of 180 ° as a constellation in the same orbit. The two identical satellites provide very high resolution optical data products in record time and allow a daily reacquisition of any point on Earth.

Missions

Studies for the satellite began in September 2000, and in October 2003 started the actual development.

Pleiades 1A was placed in a sun-synchronous orbit on December 17, 2011 at 2:03 clock ( UTC) from the Guiana Space Centre on a Soyuz -ST rocket with four Elisa satellites for the French military and the Chilean satellite SSOT. The Elisa satellites have a mass of 120 kg, and to ground-based radar sources and their characteristics for military reconnaissance capture. Prime contractor for all satellites was EADS Astrium.

Pleiades 1B was posted on December 2, 2012 at 2:02 clock ( UTC) but also placed at 180 ° from the Guiana Space Centre with a Soyuz -ST in the same orbit.

Body and Payload

The three -axis stabilized satellite is equipped with a camera with a primary mirror diameter of 65 cm, which achieve a resolution of 2 m in color or black- and-white photographs a resolution of 50 cm and multi-spectral photographs. The recordings are done by five line sensors with 1500 pixels width for multi-spectral sensors and five lines with 6000 pixels width for the panchromatic range. The satellites and their orbits were designed so that they can together accommodate any area of ​​the world at least once a day. It was built by Thales Alenia Space and has a design life of five years.

Specifications

Orbit

The two satellites are operated as a constellation, and operate in the same orbit with an angular spacing of 180 °, to provide a daily recording option for any point on the earth.

  • Orbit: sun synchronous, offset by 180 °
  • Average altitude: 700 km

Innovation

Pleiades 1A and Pleiades 1B are equipped with innovative space technology of the latest generation, such as fiber-optic gyroscopes (Fiber - Optic Gyroscope, short IFOG, fiber optic gyroscope) and control moment gyros (CMG, inertial wheel ) and therefore provide excellent roll, pitch and Schwenkagilität.

Agility for responsive tasking

Thanks to this agility in conjunction with the particularly dynamic image acquisition programming, the Pleiades system to react quickly to specific user requirements. Individual user queries are processed in record time. The input power is the underlying agility of the satellite platform in combination with the extensive strip width (20 km) due to the optical instrument. Performance data at a glance:

  • Imaging world in a 800 km wide strip of ground with sub-meter resolution
  • Along-track stereo and tri- stereo imaging
  • Single-pass collection of mosaics ( Strip mapping) in a single overflight with an area of ​​100 km x 100 km
  • Daily recording capacity of over 1,000,000 km ²
  • 50 cm black and white
  • 50 cm color
  • 200 cm multispectral
  • Blue: 430-550 nm
  • Green: 490-610 nm
  • Red: 600-720 nm
  • Near-infrared: 750-950 nm
  • Panchromatic: 480-830 nm

Applications of high -resolution images

The Pleiades system is designed for very high-resolution (Very High Resolution - VHR ) designed remote sensing applications. These include:

  • Planning: detecting and identifying objects with a size less than 1 km ² ( eg, vehicles, infrastructure, roads, bushes )
  • Agriculture: Management of land and crop yields, location of plant diseases
  • Urban planning and demography: Locations of detached houses
  • Defense: image-based information and tactical planning
  • Civil Protection: harm reduction, support in crisis situations and evaluations after a crisis (especially for earthquakes)
  • Hydrology: Investigation of topography and slope in areas of precipitation
  • Forestry: illegal logging and administration of forestry income
  • Marine and coastal monitoring: Ship reconnaissance and pollution
  • Construction: planning of roads, rail and oil pipeline corridors
Orfeo Programme SSOT (satellite) Swath width
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