ZERODUR® 8 m Mirror for Space Telescope

In 2010 ESO will celebrate the 10th anniversary of the fourth 8 m telescope Yepun's first light event. Together with the other VLT telescopes it has accumulated more than 40 years of extremely successful operation time for astronomy. Progress in rocket technology and in ZERODUR (R) light weighting gives reason for contemplating about the use of the last currently available 8.2 m blank for a space telescope. This paper will review the outstanding quality of the first four mirror blanks and present the quality of the blank still available. Additionally we will give an overview over the progress in the last decade in technology and knowledge and how they might support the use of the 8 m blank as space telescope mirror.