Free Astronomy Magazine January-February 2016

30 JANUARY-FEBRUARY 2016 ASTRONAUTICS in Technology). Unfortunately, due to bud- get cuts, the US space agency was forced to abandon the mission project, which in 2007 risked to be scrapped altogether. The origi- nal mission included the launch of three twin probes, stationed 5 million kilometres apart, constantly checking through laser beams their respective positions, in order to detect possible anomalies induced by the passage of gravitational waves (something vaguely similar to ocean buoys that signal rogue waves). Following a redesign of the mission, in 2011, ESA announced its inten- tion to continue on its own, opting for a single probe (weighing nearly 2 tons), with two small test masses, consisting of two cubes in gold and platinum alloy, of 4.6 cm per side and weighing 1.96 kg each. This time the construction of the vehicle labo- ratory was successful and its launch (from the Guiana Space Center in French Guiana, through a 4-stage Vega rocket) was set, not by chance, for 2 December 2015, on the hun- dredth anniversary of the publication of Gen- eral Relativity. A last minute hitch causes the launch to be postponed by 24 hours, which consequently takes place on 3 De- cember at 01:04 French Guiana Time. After a few orbits around Earth, LISA Path- finder started its journey to the Lagrang- S chematic representation of the key stages of LISA Pathfinder’s journey to the Lagrangian point L1, to which have been added some technical notes. [ESA/ATG medialab]