1. Introduction Gravitational waves are ripples in space-time that are generated by some of the most violent and energetic astrophysical events. This project aims to discover how far into the universe that a particularly exciting type of gravitational wave is detectable by citizen scientists listening to the data. We've simulated gravitational wave signals from the mergers of binary neutron stars and added them to real gravitational wave detector noise from the most recent LIGO science run (obtained from here). We've then converted the data into sound files where the signals sound like "chirps". Can you hear the signals in the noise? The buttons below allow you to listen to either a noise-free gravitational wave signal, the detector noise, or an example of a signal hidden in the noise. When you've familiarised yourself with the type of sound we need to you to find please move to the Training, and then Challenge sections. These sections will take approximately 5 - 10 minutes of your time and each sample is only 12 seconds long. The buttons below allow you to listen to either a noise-free gravitational wave signal, the detector noise, or an example of a signal hidden in the noise. When you've familiarised yourself with the type of sound we need to you to find please move to the Training, and then Challenge sections. These sections will take approximately 5 - 10 minutes of your time and each sample is only 12 seconds long. Please make sure that your sound is turned on and we strongly recommend that you use headphones Signal Noise Complete Sample No Sample Loaded

2. Training This section allows you to test your ability to hear signals in training samples and to get instant feedback on your performance. When you submit an answer you will be told how strong the hidden signal was in terms of its signal-to-noise ratio plus other information like how far away it was. Sometimes there may not be a signal in the data at all (so be careful). Your results are recorded from this section and from the Challenge section so try your best. Click the "Load Random Sample" button and then listen to it by clicking play (you can listen to it as many times as you need). You will then need to select one of the three options from the list below and then click the "Submit Training Response" button. Once you are confident in your detection ability, please proceed to the Challenge section and complete as many samples as you can. Load Random Sample No Sample Loaded No signal was heard Possible signal heard, not sure Signal heard Practice Results Results will show here