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Weather forecasts will improve!


When Aeolus is launched this week from ESA's Space Center in French Guiana, two Star Trackers from Terma will be on board.

Lystrup/Herlev, Denmark – When the European satellite Aeolus is launched this week  from the European Space Agency ESA’s Space Center in French Guiana, two Star Trackers from Terma will be on board.

Aeolus 464Artist's illustration of the Aeolus satellite by ESA

The Star Trackers will ensure that the satellite control system constantly knows how the satellite is oriented in space with an extremely high accuracy. Knowledge about satellite orientation is not only important in terms of control, but also for the use of the scientific measurements in general.

Europe's new wind lidar

Aeolus' primary task is to measure wind speeds in the lowermost 30 km of the atmosphere. Precise data on wind conditions and speeds is a challenge for meteorologists who, with data from Aeolus, hope to gain improved knowledge about the wind, pressure, temperature, and humidity interaction. There are thus high expectations for the satellite when it, from its orbit 320 km above Earth, starts to emit data to the European Center for Medium-Range Weather Forecasts in Reading, England. From here, a large number of national meteorological institutes are provided with data for weather forecasts.

The Star Tracker

Terma has supplied two HE-5AS Star Trackers for the main contractor of Aeolus, Airbus Defense & Space in Stevenage (UK).

A Star Tracker is basically an autonomous digital camera which, by use of a “Lost in Space” functionality, can determine a satellite’s orientation in a matter of seconds. The camera takes pictures of the sky and compares the images with a digital catalog of 5,000 star constellations. When there is a match between the camera's observations and a constellation in the computer, you know exactly how the satellite is oriented in its path around Earth. This takes place with an accuracy of 1 arc-second or 1/3600 degrees accuracy.

Terma has delivered more than 25 HE-5AS Star Trackers for a number of ESA missions and to missions under U.S. Naval Research Laboratory, U.S. Air Force Research Laboratory, U.S. National Reconnaissance Office, and U.S. Missile Defense Agency.

Aeolus 464_02Testing of Aeolus prior to launch - the two Star Trackers can be seen in the top right corner


Aeolus is currently planned for launch on Wednesday, 22 August 2018 at 21:20 GMT (23:20 CEST) from Kourou in French Guiana on the Caribbean coast of South America. It takes place on a European Vega launcher.

Aeolus is the Latin name of Aiolos, the Greek god of the Winds. The mission was adopted back in 1999 with scheduled launch in 2007, but due to major challenges in developing the Aladin scientific main instrument, the mission was delayed. The cost of the mission is approx. 480 million EUR or just over 3.5 billion DKK.

Read more at http://www.esa.int/Our_Activities/Observing_the_Earth/Aeolus

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Nils Greir
Vice President, Market Development & Strategy
T: +1 (703) 412-9410
E: nils.greir@termana.com