Sentinel (satellite)

from Wikipedia, the free encyclopedia

The Sentinel satellites are earth observation satellites of the Copernicus program (formerly GMES, Global Monitoring for Environment and Security) of the European Space Agency (ESA). The satellites have been launched as planned since 2014. Sentinel-1 is a pair of radar satellites, Sentinel-2 is a pair of passive-optical earth observation satellites, and Sentinel-3 is a pair of satellites with sensors for measuring sea ​​surface topography , sea and earth surface temperatures, and ocean color. Sentinel-5P has been studying the earth's atmosphere since 2017 ; Sentinel-4 is to follow in 2023/2030 (instruments on board Meteosat third generation satellites ).

The Copernicus program

The Copernicus program, which was created in cooperation with the EU, is intended, among other things, to enable complex earth observation with the help of the Sentinel satellites, the data of which can be used for the areas of environment, transport, economy and security policy.

Sentinel-1

The Sentinel-1 satellites will fly in a polar orbit around 700 km high and scan the earth in strips of 80 to 400 km. A C-band SAR ( Synthetic Aperture Radar ) with a wavelength of 6 centimeters is used.

Sentinel-1A was successfully launched on April 3, 2014; Sentinel-1B was launched on April 25, 2016.

Sentinel-2

Sentinel-2 also consists of two satellites in the same orbit. Sentinel-2 is intended to deliver multispectral earth observation data as a continuation of Landsat or SPOT . Images are recorded in spatial resolutions of 10 or 20 m per pixel in 10 spectral channels in the wavelength range from 443 to 2190 nm. There are also three narrow-band spectral channels with a spatial resolution of 60 m for measuring the atmospheric properties.

Sentinel-2A was launched on June 23, 2015 with a Vega rocket, Sentinel-2B was launched on March 7, 2017, also on board a Vega rocket from Kourou.

Sentinel-3

Sentinel-3 is designed to measure land and ocean colors as a continuation of the Envisat Meris instrument, land and sea temperature as a continuation of AATSR, and sea surface and ice topography as a continuation of the Envisat altimeter. There is also a radar altimeter on board. Sentinel-3 also operates as a formation of two satellites.

Sentinel-3A launched on February 16, 2016, Sentinel-3B on April 25, 2018.

Sentinel-4, -5 and -5p

The Sentinel-4 and -5 missions are dedicated to observing the composition of the atmosphere. The Sentinel-4 instruments are to fly on the geostationary Meteosat Third Generation Satellite (MTG). The Sentinel-4 mission contributes the Flexible Combined Imager (FCI) for the MTG imager satellites. On the MTG Sounder satellites (from 2019) the Sentinel-4 mission includes a spectrometer for the ultraviolet, visible and near-infrared spectral range (UVN) and a thermal infrared sounder (IRS).

Sentinel-5 is to orbit the earth in polar orbits on the MetOp second generation satellites. The mission includes a spectrometer for the ultraviolet, visible, near-infrared and short-wave infrared spectral range (UVNS) as well as a Visible Infrared Imager (VII) and a Multi-viewing Multi-channel Multi-polarization Imager (3MI). These spectral data can u. a. can be used for the creation of trace gas maps using the DOAS process . In addition, the Sentinel-5 Precursor ( Sentinel-5P ) was launched on its own satellite on October 13, 2017 , to bridge a time gap between the Envisat , MetOp and Sentinel-5 missions .

Web links

Individual evidence

  1. Programs in Progress. In: ESA Bulletin 144. ESA, November 2010, pp. 64,65 , accessed on December 21, 2010 .
  2. www.eumetsat.int
  3. Copernicus: Sentinel-5. ESA, accessed on November 5, 2017 .
  4. Sentinel-1B: The Second Eye of the Earth Guardians in Space. German Aerospace Center, April 25, 2016, accessed April 26, 2016 .
  5. Cai Tore Philippsen: The second guard is at his post. FAZ online, June 23, 2015, accessed on June 23, 2015 .
  6. Zulfikar Abbany: The Raging Scanner: Earth observation satellite, Sentinel-2B started. DW, March 7, 2017, accessed March 7, 2017 (German).
  7. ESA's Sentinel satellites - Sentinel-3. (PDF; 215 kB) ESA, August 2013, accessed on January 12, 2014 (English).
  8. ^ Third Sentinel satellite launched for Copernicus. ESA, February 16, 2016, accessed on February 16, 2016 .
  9. ^ ESA: Seventh Sentinel satellite launched for Copernicus. April 25, 2018, accessed April 26, 2018 .
  10. Eurockot: Sentinel-5P on Rockot Facts and Figures. (PDF) Accessed November 23, 2015 .
  11. ^ Launch Schedule. Spaceflight Now, August 26, 2017, accessed August 27, 2017 .