Author Archives: Kourou Project Team

Gaia payload module integration

One month at L2

Gaia has been in its operational orbit around L2 for about a month now, where it is undergoing a very rigorous test programme before starting on its main science observations. Like many relocations, it can take some...

A secretary in the jungle

If you are anticipating a technical blog – stop reading this now, as I am surely the least technical person in the Gaia Project Team. Let me introduce myself, I am Helma, the Gaia project secretary. I’ve been on the project since day one, which is about ten years ago, so I sometimes joke about Gaia being my first baby (I’ve had two actual babies in the meantime). When people ask me why I have to go French Guiana for months I tell them ‘to support our Launch Campaign’. Then I get ‘Yes but what do you actually do?’ Besides the normal work like documentation, handling timesheets, leave requests, and a million...

Gaia is whole again

After a month full of uncertainties, Gaia transponders are back and in good health. Following their business class return flight to Kourou, both Gaia transponders have been re-integrated in the spacecraft, re-connected, and functionally verified. At the completion of five days of intensive testing, all results were positive, allowing the re-installation of the solar array panels and of the multilayer insulation (MLI) blankets, which had to be removed for operator access (see picture). This progress allows the team to reaffirm the recently agreed launch date of 19 December. As of Monday 25 November, we will be able to resume the spacecraft preparation, beginning with pressurisation of the gas tanks. This is a...

We are back!

Of course you have all noted that when we started our blog the launch date of Gaia was 20th November and now the countdown to launch shows 20th December. Why is that? Let’s start from the beginning. On Saturday, 19th October, at about 16:30 when I was shutting down the computer in my office in Kourou and preparing for a sunny Sunday, I received a phone call from the person responsible for one of the key systems embarked on the spacecraft. There had been a failure on a satellite already in orbit and the analysis of the failure pointed towards a design mistake. The consequence was that the lifetime of a tiny...

Some Gaia numbers

We have heard and read many numbers about Gaia: the number of stars and other objects that it will observe, the maximum observable magnitude, the microarcsecond of accuracy and the remarkable focal length of 35 m. We have also read that such a powerful telescope on Earth would be able to detect a button on the spacesuit of an astronaut on the Moon. But let’s look at more hidden numbers. It took over 3.5 million hours to study, design, build and test Gaia. That’s about 300 people working full time for 7 years, spread over 74 different companies and 16 countries. Meanwhile the design and implementation of the science and the operations...

The pieces of the puzzle are coming together

The activities on the spacecraft are almost finished. The great achievement of last week was the smooth deployment of the sunshield. The Astrium and Sener teams are now giving the final touch to configure the satellite for flight. This week we will check for the last time the leak tightness of the propellant tanks and then Gaia will be ready to move to another building (called S5A) where it will be fuelled. With Gaia almost ready it was time to have a look to other pieces of the puzzle. We therefore paid a visit to the MIK building (MIK is the Russian acronym for the huge hall where the three stages of...

Pyrotechnic and 24 bangs: The sunshield deployment

Several cameras have been strategically positioned around the spacecraft and programmed to take a picture every 3 seconds. Inside the cleanroom, utter silence pervades, which is interrupted only by the regular clicking of the cameras. Three windows provide a view of the cleanroom from the rooms outside. Behind those windows, the rooms teem with people. All eyes are glued to the spacecraft. The anticipation in the air is sliced by the sudden ringing of a red telephone on the wall. We’ve been expecting the call: the software team is ready to command the deployment sequence. There is only time for one last quick check: are we good to go? The team leader...

Installing the Gaia Sunshield

Six in the morning in Kourou: outside it is still dark, but the thermometers are already reading 24 degrees Celsius, and the relative humidity has remained 92% through the night. After sunrise at 06:18 today, the temperature will climb to reach a maximum of 34 degrees in the afternoon. The Gaia spacecraft, however, is inside the cleanroom, where the temperature is maintained at a constant 23 degrees. Air is circulated through filters to preserve a clean environment, and the humidity in the cleanroom will be kept at about 50%. In the airlock leading to the cleanroom, the Astrium Assembly, Integration and Testing (AIT) team and the SENER Sunshield team are getting ready...

Hiding from the Sun

Halfway between the Caribbean Sea and the Amazonian rain forest, French Guiana offers amazing nature and some incredible photo opportunities. But trying to find the best views will have you wandering around under the scorching tropical Sun. How about carrying with you a good old beach umbrella to protect yourself from the burning Sun while keeping an unobstructed sight of the landscape around you? Now, think about a large beach umbrella. And I mean a really large one. To be precise 10.5 metres in diameter, with a surface area of 90 square metres. That’s almost the size of half a tennis court, or an area large enough to park three passenger buses!...

Another day in the life of a Gaia test engineer

In the middle of last night, we received in Kourou a disturbing call from the Gaia control centre, located in Darmstadt, Germany. Although for us it was middle of the night, it was already morning in the control centre. So what happened? Although often announced in the media as having the biggest camera on board that has ever flown in space, Gaia does not actually take pictures in the sense as you and me taking pictures on a holiday trip. Instead, it rather tracks the stars across its sensors as the telescopes rotates and the field of view moves across the star filled sky. In order to do so, a constant readout...