gravity waves!!!! when was it last measured?

Answer 1

Gravity waves have never been detected directly. There is an experiment called LIGO whose intention it so do just that. It's a work in progress, though. GW's have been inferred as the cause of orbital decay in close binary stars that *has* been observed. GW's are a firm prediction of General relativity, and the decay rate is consistent with GR. LIGO is expected to be able to detect the burst of GW's from merging binary neutron stars and black holes in nearby galaxies after such orbital decay takes its course. The expected wavelength *has* been predicted. It's a few hundred km, I think (LIGO is quite large)

Answer 2

its never been measured or detected for that matter.Gravity waves must exist however they are very weak and their wavelength is completely unknown.