Monthly Archives: October 2013

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...

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Mapping the Milky Way with Gaia

Latest ESA Euronews video looks at Gaia and explains how it will scan the sky with powerful new eyes, mapping the Milky Way in unprecedented detail.

Gaia: launch postponed

Due to recently-discovered technical issues with a separate satellite, ESA has decided to perform additional precautionary verifications on its Gaia satellite. Therefore we have requested that Arianespace postpone the Gaia launch, currently scheduled for November 20, 2013. More details will be given as soon as they are available and the new launch date will be announced when the timeline for completing the additional work has been confirmed. Updated 29 October: The upcoming launch manifest of Arianespace has now been established. Gaia is scheduled for launch on 20 December. For additional information on the postponement, see latest update on the ESA Portal.

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...

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Gaia sunshield deployment time lapse sequence

Here are some nice time-lapse sequences from the deployment test of the Gaia Deployable Sunshield Assembly (DSA) on 10 October 2013, in the cleanroom at Europe’s spaceport in Kourou.     Since the DSA will operate in microgravity, it is not designed to support its own weight in the one-g environment at Earth’s surface. Therefore, during deployment testing on the ground, the DSA panels are attached to a system of support cables and counterweights that bears their weight, preventing damage and providing a realistic test environment. Once in space, the sunshield has two purposes: to shade Gaia’s sensitive telescopes and cameras, and to provide power to operate the spacecraft. Gaia will always...

Trip of a lifetime: Young ESA’s visit to Kourou

Ever flew over Kourou? Ever climbed a palm tree? Ever slept in a hammock in the jungle? Ever been to paradise with the devil around the corner? We, some of the Young ESA members, were the lucky ones who actually experienced it all in French Guiana two weeks ago. It was possible thanks to the perfect organization of Juan de Dalmau who guided us for a week through the culture, nature and spaceport – and yes, it was great fun! We had the chance to learn about the culture in French Guiana as well as taste the rainforest life! During the first days we visited Cayenne and its traditional market, spent some...

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...

Opening (activating) the gates of Gaia

As you may know already from previous blog entries Gaia will fly the biggest camera ever into space. The image created by the two telescopes will be huge: about 1 m wide and 0.5 m high. To cover this entire area you need 106 different CCDs (detectors). Most of them are white light CCDs. Additionally there are blue sensitive (BP) and red sensitive (RP) CCDs. About one billion pixels (picture elements) are distributed over the focal plane as each CCD consists of about 9 million pixels. CCD images can have saturated pixels as you may have experienced with your digital camera when taking photos or videos and a bright light source is...

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!...