For more information about this cache series, see here.
INTERSTELLAR SIGNAL
ALERT: The link below leads to a web page where you can hear an audio file. No download is necessary, but an option to download it is available. If you do choose to download the file, you do so at your own risk; while Team Otago has checked and ensured the file is free of any malware, neither Geocaching HQ or reviewers have checked the file.
Audio file required to solve this puzzle.