The first proof of gravitational waves is within reach, but gravitational wave astronomy first and foremost requires us to look to the future. Even now, researchers are contemplating what third and fourth generation gravitational wave detectors may be like. They have set their sights high, because the deep sounds – in other words the gravitational waves generated by really big black holes – can only be heard in space. With this goal in their sights, they are already planning to launch an important international satellite mission in 2020, but even now they are already looking for the minute signals produced by gravitational waves in the noisy data collected by the detectors. Who will be the first to find the needle in the haystack of space?