Total Solar Eclipse, Palm Cove, Queensland, Nov. 14th 2012

Eclipse photo gallery

A gravitational wave symphony

This one's just for fun. Unlike regular Astronomy where we observe light, gravitational waves - the ripples in space-time predicted from Einstein's theory of gravity to be generated by the motion of matter - are best interpreted as a kind of sound. In fact, the frequencies of gravitational waves in the LIGO interferometer fall within our audible hearing range. The above is a mix-up of simulated gravitational waveforms expected from the merger of binary black hole and neutron star systems. The long, deep ones are the supermassive black-hole binaries that will be detected by LISA, if it ever flies. These have been scaled up in frequency to be represented as audible sounds. The short "chirps" are the final death-throes of stellar-mass black hole binary systems (i.e. two dead stars finally merging together). Pretty soon we should actually detect some real gravitational waves, so maybe then I'll make a follow-up with the *real* sounds of the Universe. Until then, enjoy...

Credit for sample waveforms and more info at: Scott Hughes' gravitational wave page (and older page here).
Download .mp3 file here

Youtube version: