The launch of the European Space Agency’s Gaia mission has been postponed after a technical issue was identified in another satellite already in orbit.
Gaia is ESA’s billion-star surveyor, designed to provide a precise 3D map of our Milky Way galaxy in order to understand its composition, formation, and evolution.
ESA said the spacecraft’s sunshield passed the final deployment test in the cleanroom earlier in October. After launch this shield will be deployed to form a 34-ft.-wide “skirt” around Gaia’s base, helping to shade the spacecraft’s sensitive telescopes and cameras from sunlight while also providing solar power.
Gaia shares some of the components involved in this technical issue and prompt notification of this problem has allowed engineers working on the final preparations for Gaia’s launch to take additional precautionary measures.
The issue concerns components used in two transponders on Gaia that generate “timing signals” for downlinking the science telemetry. To avoid potential problems, they will be replaced.
The transponders will be removed from Gaia at Kourou and returned to Europe, where the potentially faulty components will be replaced and verified. After the replacements have been made, the transponders will be refitted to Gaia and a final verification test made.
As a consequence of these precautionary measures, it will not be possible to launch Gaia within the window that includes the previously targeted launch date of Nov. 20. The next available launch window is Dec. 17 to Jan. 5. The new launch date will be announced when the timeline for completing the additional work has been confirmed and the overall launch manifest of Arianespace has been established.
Release Date: October 23, 2013
Source: European Space Agency