Here is another photo of the Gipparcos telescope.
Hipparcos satellite: testing in the Large Solar Simulator, ESTEC. Michael Perryman - own work.Added after 9 minutes 54 seconds:
Let's build the youngest telescope with the simplest geometric shapes? This is Gaia's telescope!
Model of Gaia Paris Air Show 2013. User:Pline
On April 25, 2018, the European Space Agency published on its website  the most detailed three-dimensional map of our galaxy in the history of mankind, containing information on the exact location and movement of almost 1.7 billion stars, as well as about 14 thousand asteroids of the solar system. The second data set (English Data Release 2, DR2) was held from July 25, 2014 to May 23, 2016. It is planned that Gaia will transmit information to Earth until 2020 to improve the 3D map