The Lisa Pathfinder is a unique gravitational spacecraft that will be on the forefront of detecting “gravitational waves “from space has just successfully completed the first part of its mission in orbit. The Lisa Pathfinder has released two 2kg gold-platinum cubes, which are free-falling inside the spacecraft.
The spacecraft is designed to measure the relative positions of the cubes using a laser. Lisa then moves around the cubes using micro-thrusters. The masses appear to be falling “freely through space.”
The results mean the cubes have not been impacted by any solar radiation or winds—only “minuscule” forces have affected the spacecraft.
“The measurements done by this first laser interferometer in space are by far better than we had expected,” Gerhard Heinzel from Leibniz Universität Hannover said. “We can determine the distance of the two free-falling test masses to less than the diameter of a single atom.”
The spacecraft is meant to be a precursor to a space “observatory” designed exclusively for detecting gravitational waves. The waves are ripples in the curvature of space-time, and were first detected by a team of researchers during the final fraction of a second during the merging of two black holes.
Their existence was predicted by Einstein more than a century ago.