Alphasat experiences heaven on Earth

February 8, 2013, European Space Agency
Alphasat inside the Intespace Simmer vacuum chamber.  The team completes final preparations before the start of the test. Credit: Astrium

(—Tucked away in a vacuum chamber for several months, Europe's largest telecom satellite has faced the harsh conditions it will deal with once it is launched into space this summer.

Testing at Intespace in Toulouse, France, simulated conditions close to those Alphasat will experience in flight, including the intense cold of its transfer orbits in the early stages of the mission.

Not only was Alphasat's ability to control its temperature tested, but other features were also put through their paces to ensure everything can run under the extreme cold and hot conditions.

"If you were going to test a new car for , you would probably want to do the same thing: not only check the heating and air conditioning, but also make sure that the engine, brakes, ignition and radio work in low temperatures as well as high," explained Philippe Sivac, ESA's Alphasat acting project manager.

To monitor the satellite inside the large chamber, nearly 600 were attached in key locations. A satellite the size of Alphasat can also carry up to 400 flight .

Readouts are displayed in real time, together with the satellite's internal data to help build an overall picture for the team monitoring Alphasat around the clock.

Running Alphasat under very stable thermal situations showed that the thermal- is well suited to predict the temperatures in .

Alphasat is prepared for the thermal–vacuum chamber. Credit: Astrium

"Finally, the performance and functional tests show that all the electronics and software perform as expected even at ."

However, the model will further be checked and refined where needed.  "This will require a lot of data processing to adjust the thermal model and make it fit to the measurements gathered during the test," notes Philippe.

Engineers took this opportunity to test new methods and tools that will speed up the processing of such large amounts of information.

All satellites endure a similar series of demanding tests before they are considered to be qualified for launch. Usually it takes about a month, but Alphasat is not quite like other telecom satellites.

Five engineers from ESA worked around-the-clock throughout the extended tests, even working through the Christmas break.

"The complexity of the payload, the number of redundancies and configurations to test and customer specific requirements required testing to exceed two months," says Philippe.

And that's not all. While the 10 m-long, 8 m-diameter chamber was large enough for Alphasat, the handling equipment had to be modified to accommodate the massive satellite.

Alphasat is a high-power telecom satellite built by Astrium, through a public–private partnership between ESA and UK operator Inmarsat.

It is based on the mighty Alphabus, the new European telecom platform developed by Astrium and Thales Alenia Space under joint contract from ESA and the French space agency, CNES.

Alphabus is Europe's response to increased market pressure for larger telecom payloads for direct-to-home TV broadcasting, digital audio broadcasting, broadband access and mobile services.

Launch is expected this summer aboard an Ariane 5 from Europe's Spaceport in French Guiana.

Explore further: When a bus becomes a satellite

Related Stories

When a bus becomes a satellite

March 18, 2011

Alphabus has met Alphasat. Europe's largest telecom satellite is taking shape with final assembly and testing ready to begin in Toulouse, France.

ESA and Inmarsat prepare for Alphasat

June 20, 2007

Today at the Paris Air Show, ESA and Inmarsat moved closer to the implementation of Alphasat, the first satellite based on Alphabus, the new European telecommunications platform.

First journey for Alphabus spacecraft

February 5, 2010

( -- The service module of the new Alphabus generation of telecommunication satellites has completed its first journey ? from Cannes to Toulouse, in France. The three-day trip was completed last Friday.

Hylas gets green light for spaceport trip

September 29, 2010

( -- Following extensive testing in India, the Hylas-1 telecommunication satellite has been given the go-ahead for shipping to Europe?s Spaceport in French Guiana for its November flight.

LEON: The space chip that Europe built

January 8, 2013

(—Just like home computers, the sophisticated capabilities of today's space missions are made possible by the power of their processor chips. ESA's coming Alphasat telecom satellite, the Proba-V microsatellite, ...

Hylas satellite on schedule for launch

June 4, 2010

( -- The completion of important tests on the Hylas telecommunications satellite has brought it a step closer to launch late this year. Once the final tests are completed, Hylas will be ready to be shipped to ...

Recommended for you

Asteroid 2002 AJ129 to fly safely past Earth February 4

January 22, 2018

Asteroid 2002 AJ129 will make a close approach to Earth on Feb. 4, 2018 at 1:30 p.m. PST (4:30 p.m. EST / 21:30 UTC). At the time of closest approach, the asteroid will be no closer than 10 times the distance between Earth ...

A new bound on axions

January 22, 2018

An axion is a hypothetical elementary particle whose existence was postulated in order to explain why certain subatomic reactions appear to violate basic symmetry constraints, in particular symmetry in time. The 1980 Nobel ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.