UPSC Civil Services 2020 Prelims General Studies Paper I

The Evolved Laser Interferometer Space Antenna, or eLISA, is one of the most interesting offworld scientific experiments underway today. eLISA relies upon a stable configuration of three discrete satellites. Each craft is separated by a gap of one million kilometers, or roughly 621,000 miles, arranged to form the vertices of an enormous equilateral triangle in space. The lines connecting this titanic piece of interstellar geometry are drawn, point to point, by laser beams.