Complex sentence: The Yebes Observatory RT40m, or ARIESXXI, is a 40 metre Cassegrain-Nasmyth telescope that is located at the Technological Development Centre (CDT) in Yebes, Spain.
Split into simpler sentences: The Yebes Observatory RT40m, or ARIESXXI, is a 40 metre Cassegrain-Nasmyth telescope. The telescope is located at the Technological Development Centre (CDT) in Yebes, Spain.