Tag Archives: launch

ESOC Green for launch

A quick update from ESOC, ESA's mission control centre for Gaia: Winds (high-altitude), weather and solar activity are all green for launch ESA's Estrack ground station network reports all stations involved GO for launch Stations at Perth,...

Gaia lift-off timeline

Find below a detailed timeline for the launch of Gaia on 19 December 2013. See notes for abbreviations. The usual disclaimer applies: This is a real-time activity and all times are subject to change. Follow launch live via ESA TV, starting 08:50 GMT (09:50 CET). See also some additional post-separation timeline events listed in Gaia liftoff timeline in ESA web. AIT - The Astrium Integration Team/Suupport Team in Kourou, working on behalf of the ESA Gaia Project Office DMS - Soyuz Mission Director on console at Kourou S/C - Spacecraft (= Gaia) MET - Mission elapsed time (minue before H0, positive after) MET UTC Actor Activity -14:00:00 19:12:19 ESOC B-Team...

Installation on the launch adapter

Following the filling of the tanks, the Gaia satellite enters the Combined Operations Phase: the “COP”. This involves all the different stages by which the satellite is put on to the launcher, the launcher is put on the launch pad, and the launch itself. All of the activities on the satellite are carried out at this time according to a schedule established by Arianespace, who also manage all of the active participants of this combined phase: Astrium as the prime contractors of the satellite, Roscosmos for the Russian launcher, RUAG for the payload adapter and the clamp band, Arianespace or its subcontractors for the electrical testing of the launcher, and CNES for...

Gaia ready for fuelling

Towards the end of November, the first part of the Gaia launch preparation was complete: the satellite was 90% ready, with its tanks pressurised. The second part begins with filling the tanks with the appropriate propellants. This phase is particularly dangerous because the propellants are toxic, and there is also a risk of explosion, so it is carried out in a dedicated building. That’s why Gaia had to move from building S1B in the payload preparation complex (EPCU), where it has been since the start of the campaign, to the S5 building to be fuelled. How do you move Gaia from one building to another? Gaia, complete with its sunshield, could not...

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...

Gaia launch set for 19 December

The checks on the Gaia satellite are proceeding well, enabling the launch to take place on Thursday, 19 December. The exact time of launch is 09:12:18 UTC (10:12:18 CET), which is 06:12:18 local time in French Guiana.

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...

Gaia lift-off time

Launching a satellite seems fairly simple: put it onto a rocket and launch it into space. Of course it's a bit more complicated than this and some missions are more complex than others. In the case of Gaia we have to launch at a very specific time each day. This lift-off time is determined by the Libration Point Mission Analysis Group of ESOC. In this blog entry I'll explain why this launch time is so constrained and how we determine the exact lift-off time. There are three major factors that contribute to this launch: - The destination of Gaia, the Sun-Earth libration point, or Lagrange point 2 - The programming of the...

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...

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.

Inspecting the Soyuz facilities

The previous blog entries have given an overview of the activities of the last few weeks: from the arrival of the spacecraft in Kourou to the successful test of the Launch and Acquisition Mode (LAM) - the initial operational mode of the spacecraft during and after launch up to the contact with the ground stations. Another recent activity was the inspection of the Soyuz facilities and especially the VS06 rocket (Soyuz Flight number 6), which will now launch Gaia, after the switch with the O3B project. The first thing that catches your eye is a depot with 40 massive containers that are shipped from St. Petersburg by boat. The Soyuz facility stores...