Solution:The experiment in question refers to evolved Laser Interferometer Space Antenna (eLISA) which is a proposed space probe to detect and accurately measure gravitational waves. It is a space-based gravitational wave observatory building on the success of LISA Pathfinder and LIGO. The European Space Agency (ESA) is leading this mission with support from NASA and an international consortium of scientists. eLISA is a spectacular plan of setting into space three spacecraft, a mother and two daughter spacecraft, which will fly in a triangular formation, trailing the Earth in its orbit around the sun at a distance of over 50 million km.
Each arm of the imaginary equilateral triangle will measure about a million km. The distance between the spacecrafts is precisely monitored by laser interferometers to detect passing gravitational waves. This mission is slated for 2034.