ADM-Aeolus

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Aeolus
ADM-Aeolus.jpg
Artist's view of Aeolus
Mission type Weather satellite
Operator ESA
Mission duration 3 years (planned)
Spacecraft properties
Manufacturer Airbus Defence and Space
Launch mass 1,366 kg (3,012 lb)
Dry mass 1,200 kg (2,600 lb)
Dimensions 1.74m × 1.9m × 2m
Start of mission
Launch date 21 August 2018[1]
Rocket Vega
Launch site Kourou ELV
Contractor Arianespace
Orbital parameters
Reference system Geocentric
Regime Sun-synchronous
Altitude 320 km (200 mi)[2]
Inclination 97 degrees
Repeat interval 7 days
Epoch Planned
Transponders
Band S band (TT&C support)
X band (science data acquisition)
Bandwidth 8 kbit/s download (S band)
10 Mbit/s download (X band)
2kbit /s upload (S band)
Instruments
ALADIN: Atmospheric LAser Doppler INstrument
← Swarm

Aeolus, or, in full, Atmospheric Dynamics Mission Aeolus, is an Earth observation satellite built by Airbus Defence and Space that is due for launch in August 2018.[1] ADM-Aeolus will be the first satellite with equipment capable of performing global wind-component-profile observation and will provide much-needed information to improve weather forecasting.[3] Aeolus will be the first satellite capable of observing what the winds are doing on Earth, from the surface of the planet and into the stratosphere 30 km high.

In Greek mythology, Aeolus is the name of the ruler of the winds.

Program[edit]

The program was initially approved in 1999 for a 2007 launch but technological obstacles caused 11 years of delay, as it is scheduled for 21 August 2018. For an estimated €481 million ($568 million) program cost, it should provide 64,000 daily profiles from March or April 2019. Its altitude is a low 320 km (200 mi)[2] for enough backscattered light sensibility, inducing a short 3.25 years life expectancy.[4]

Satellite[edit]

The Aeolus is the fifth planned satellite in the Living Planet Programme of the European Space Agency (ESA). The main goal of this mission is to further develop the knowledge of Earth's atmosphere and weather systems. By recording and monitoring the weather in different parts of the world, Aeolus will allow scientists to build complex weather models, which can then be used to help predict how that environment will behave in the future. These predictions will be useful in the short-term, since they can be applied to Numerical Weather Prediction in order to make forecasts more accurate. The mission will thus improve the knowledge of all sorts of weather phenomena, from global warming to the effects of air pollution. Aeolus is seen as a mission that will pave the way for future operational meteorological satellites dedicated to study Earth's wind profiles.

The spacecraft is being built by Airbus Defence and Space.[5] In 2014 integration of ALADIN was completed and vacuum along with vibration testing begun.[6]:70

Scientific payload[edit]

The wind-component profiles will be measured by the Atmospheric LAser Doppler INstrument (ALADIN).

ALADIN[edit]

The ALADIN instrument (Atmospheric LAser Doppler INstrument) is a direct detection ultraviolet laser lidar consisting of three major elements: a transmitter, a combined Mie and Rayleigh backscattering receiver assembly, and a Cassegrain telescope with a 1.5 metres (4.9 ft) diameter.[7] The transmitter architecture is based on a 150 mJ diode-pumped frequency-tripled Nd:YAG laser operating in the ultraviolet at 355 nm.[7] The Mie receiver consists of a Fizeau spectrometer with a resolution of 100 MHz (equivalent to 18 m/s). The received backscatter signal produces a linear fringe whose position is directly linked to the wind velocity; the wind speed is determined by the fringe centroid position to better than a tenth of the resolution (1.8 m/s).[7] The Raleigh receiver employs a dual-filter Fabry–Pérot interferometer with a 2 GHz resolution and 5 GHz spacing. It analyzes the wings of the Rayleigh spectrum with a CCD; the etalon is split into two zones, which are imaged separately on the detector.[7]

The processing of the backscatter signals will produce line-of-sight wind-component profiles above thick clouds or down to the surface in clear air along the satellite track, every 200 kilometres (120 mi). Wind information in thin cloud or at the tops of thick clouds is also attainable; from the data processing, information on other elements like clouds and aerosols can also be extracted. The data will be disseminated to the main NWP-centres in near-real-time.

Development of the ALADIN instrument has been problematic. The ultraviolet laser was causing damage to the optical surfaces in a vacuum. ESA scientists asked NASA for support, however NASA has minimal experience with lidar of this design. Technology required for the satellite was pushing the technology envelope, therefore after problematic development ESA asked Airbus to perform additional full-model tests in a vacuum before continuing mission development. Overall complications involved in the instrument caused an estimated 50% final cost overrun; ESA has agreed to come with additional funding for the project.[8]

Launch[edit]

Aeolus was designed to be compatible with many small-capacity launch vehicles such as Vega, Rockot or Dnepr.[9] In November 2013 ESA scheduled the launch on a VEGA in one of the five flights of the VERTA Programme,[5][10] but in 2015 launch was postponed to August 2018 due to problems with their lidar development.[8] A €32.57 million launch contract with Arianespace was signed on 7 September 2016.[11] The launch is currently scheduled for 21 August 2018.[12]

See also[edit]

ESA's Living Planet Programme:

References[edit]

  1. ^ a b "Aeolus Fuelled". ESA. Retrieved 5 August 2018. 
  2. ^ a b ADM-Aeolus operations. ESA. Accessed 12 June 2018.
  3. ^ "Tellus A: Special issue with manuscripts related to ESA's Atmospheric Dynamics Mission/Aeolus". Bibcode:2008TellA..60..189K. doi:10.1111/j.1600-0870.2007.00296.x. 
  4. ^ Thierry Dubois (Jun 12, 2018). "ESA's Aeolus Satellite To Gauge Wind Globally". Aviation Week & Space Technology. 
  5. ^ a b "Aeolus: wind monitoring". Airbus Defence and Space. Retrieved 30 May 2015. 
  6. ^ "ESA Bulletin 161 (1st quarter 2015)" (PDF). ESA. 2015. ISSN 0376-4265. Retrieved 30 May 2015. 
  7. ^ a b c d "ADM-Aeolus (Atmospheric Dynamics Mission)". ESA. Retrieved 30 May 2015. 
  8. ^ a b de Selding, Peter B. (22 May 2015). "Cost, Schedule Woes on 2 Lidar Missions Push ESA To Change Contract Procedures". Spacenews. Retrieved 4 June 2015. 
  9. ^ "ADM-Aeolus operations". ESA. 7 December 2012. Retrieved 30 May 2015. 
  10. ^ "VERTA Programme". ESA. 20 November 2013. Retrieved 30 May 2015. 
  11. ^ "Vega to launch ESA's wind mission". ESA. 7 September 2016. Retrieved 7 September 2016. 
  12. ^ "Satellite: ADM-Aeolus". World Meteorological Organization. Retrieved 19 September 2017. 

External links[edit]