ESA: Eutelsat-9B satellite with its EDRS-A payload

The Eutelsat-9B satellite with its EDRS-A payload is shown in the anechoic test chamber of Airbus Defence and Space (EADS) in Toulouse, France. It completed its final antenna pattern tests today.

EDRS-A is a hosted package as the first of two nodes of the European Data Relay System set to be launched next year.

Also known as Europe’s SpaceDataHighway, EDRS will use cutting-edge laser technology to capture and relay information gathered by Earth-observing satellites.

By travelling via EDRS’s high-speed links and stationary position over Europe, the satellites’ data reach the ground in near-real time.

While EDRS-A’s Laser Communication Terminal is being checked for flight, the terminals on Copernicus’ Sentinel-1A and Alphasat telecom satellite are already fully operational in space, ready to demonstrate their ground-breaking capabilities for multi-gigabit optical communications in space.

On Friday, 28 November the first Earth observation image gathered by Sentinel-1A and relayed to a ground station at the DLR German Aerospace Center in Oberpfaffenhofen,

Germany, via Alphasat will be presented at an event at ESA’s European Space Operations Centre in Darmstadt, Germany.

ESA Sentinel 1A: Image of Netherlands from Space - Video

Radar image of the Netherlands. 

Credit: ESA

This image over the West Coast of the Netherlands is one of the early radar scans by the Sentinel-1A satellite, which was launched on 3 April.

The satellite's advanced radar can provide imagery under all weather conditions and regardless of whether it is day or night.

It can scan Earth's surface in a range of different modes, enabling it to monitor large areas in lower resolution or to zoom in on a smaller region for a sharper view.

One of the many application areas of the data will be the surveillance of the marine environment, including monitoring oil spills and detecting ships for maritime security, as well as measuring wave height.

In this image, we can clearly see radar reflections from the ships at sea, appearing like stars in a night sky.

The two collections of 'stars' are reflections from large-scale offshore wind farms, used to generate electricity.

Other visible features include the city of Amsterdam on the centre-right side of the image, and the runways of the nearby Schiphol airport.

In the lower part of the image we can see the city of Rotterdam, with Europe's largest port extending to the left.

Sentinel-1's radar will also be used for monitoring changes in agricultural land cover – important information for areas with intensive agriculture like the Netherlands.



This image, also featured on the ESA Earth from Space video programme, was acquired on 15 April with the radar operating in 'stripmap mode', which provides coverage at a resolution of about 10 m.

Sentinel-1A is the first in a fleet of satellites being developed for Europe's Copernicus environmental monitoring programme.

The satellite is not yet in its operational orbit, but early images like this have given us a taste of what's to come.

ESA Sentinel 1A: First radar vision for Copernicus

Brussels from Sentinel-1A. Credit: ESA

Launched on 3 April, ESA's Sentinel-1A satellite has already delivered its first radar images of Earth.

They offer a tantalising glimpse of the kind of operational imagery that this new mission will provide for Europe's ambitious Copernicus environmental monitoring programme.

Rather aptly, the first image shows Brussels in Belgium, the seat of the European Commission.

The European Commission leads the Copernicus programme and coordinates the broad range of services to improve the management of the environment and to safeguard everyday lives.

ESA is responsible for developing the family of Sentinel satellites and for ensuring that the stream of data are available for these services.

This first image of Belgium was captured on 12 April, just one day after the satellite was put into its operational attitude, and demonstrates the potential of Sentinel-1A's radar vision.

Since it was launched from Europe's Spaceport in French Guiana, Sentinel-1A has undertaken a complicated routine to deploy its 12-m long radar and two 10-m long solar wings, as well as passing a series of initial instrument checks.

The satellite is not yet in its operational orbit, nor is it calibrated for supplying true data. These tasks will be carried out during the commissioning phase, which will take about three months to complete.

This preliminary set of images simply offer a taster of what's to come.

One of the images acquired on the same day focuses on Pine Island Glacier in Antarctica. 

This glacier is in a state of 'irreversible retreat' so it is important to keep a very close eye on glaciers such as these as they lose ice to the ocean.

Another shows a transect over the northern part of the Antarctica Peninsula.

As well as monitoring glaciers, Sentinel-1A is poised to generate timely maps of sea-ice conditions, particularly for the increasingly busy Arctic waters.

Images from its advanced radar can be used to distinguish clearly between the thinner more navigable first-year ice and the hazardous, much thicker multiyear ice to help assure safe year-round navigation in polar waters.

As these first images show, Sentinel-1A is already demonstrating the vital role it will play in the largest civil Earth observation programme ever conceived.

ESA Sentinel 1A: Collision Avoidance maneuvre to avoid dead satellite

At the end of the first day after the launch (4 April): all deployments have been executed during the night and completed early in the morning at the beginning of the first ‘day shift’.

As the first day shift nears its end, a serious alert is received: there is a danger of a collision with a NASA satellite called ACRIMSAT, which has run out of fuel and can no longer be manoeuvred.

A collision avoidance manoeuvre during LEOP has never been done before, and has not been simulated.

The satellite had not yet reached its ‘normal pointing mode’, the ESA team could not manoeuvre it before this milestone was reached.

But there was no alternative. After a brief team consultation Juan, the ‘day shift’ Deputy Flight Operation Director, decided to start preparing the satellite in case a manoeuvre was needed, and it was to be executed by his colleagues on the night shift.

It is decided to manoeuvre Sentinel-1A. Its orbit altitude needs to be changed to escape the chaser satellite (debris).

The manoeuvre takes 39 seconds. The sequence of commands was uplinked during pass 37 over Alaska/Svalbard/Kiruna/ at 04:33 UTC for execution at 05:14 UTC, outside visibility.

The atmosphere was tense and the Main Control Room was filled with suspense.

All eyes were watching the big screens on the wall, waiting for a sign, good or bad.

As the satellite approached Troll ground station on the next pass and the telemetry started to scroll down in the twilight of the control room, the team held their breath.

But there was no need for concern. The satellite was in Orbit Control Mode and the GPS on-board showed a change in its orbit status.

The manoeuvre had been a complete success. The collision and premature end of the mission had been avoided. Just another day in the office for the ESA Flight Operations team.

But it does highlight the need for continued vigilance in the debris littered orbits around the Earth. A more permanent solution is vital to allow the continued use of Earth orbits for scientific research.

ESA: Sentinel 1A Launched - Video

Sentinel-1A, the first satellite for Europe's environmental monitoring Copernicus programme, launched from Europe's Spaceport in Kourou, French Guiana on 3 April 2014. It was lofted into orbit on a Soyuz rocket.

This animation shows some of the critical stages delivering Sentinel-1 into orbit around Earth. After separating from the Fregat upper stage, the satellite takes around 10 hours to deploy its 12 m-long radar and two 10 m-long solar wings.

This deployment sequence is unique, choreographed to ensure that both deploy in the safest possible way. This approach also allows power from the wings to be available as soon as possible so that the satellite is independent.

Delivering vital information for numerous operational services, from monitoring ice in the polar oceans to tracking land subsidence, Sentinel-1 will play a key role in the largest civil Earth-observation programme ever conceived.

The animation is set to a track called Sentinel by Mike Oldfield, a world-renowned musician and big space fan.

Credit: ESA