This voice experience is generated by AI. Learn more. This voice experience is generated by AI. Learn more. The Milky Way galaxy has more than 400 billion stars in it. Over the last few decades, ...

Astronomer Geoff Marcy is the Usain Bolt of planet hunters, but now he is turning his gaze towards potential alien civilisations. The good news, he tells Anil Ananthaswamy, is that ET may already be ...