Ever worry about shadowy forces tapping into your phone calls and listening in on your private conversations? Well, astronomers have some good news for you: It won’t be aliens with their ears (or whatever auditory sensory organs they evolved) to the speaker getting into your business.

At least, not yet. Unless they’ve done a lot better than we have funding radio astronomers. And only if they’re really close by.

Scientists with SETI—the search for extraterrestrial intelligence—have long pondered how to detect life outside Earth. Assuming there are technologically advanced aliens out there, they might be trying to communicate with us. Or they might just be leaking radio energy into the cosmos by accident. Either way, can we pick up that signal?

One way to tackle this question is to turn it around: We know how much energy we’re broadcasting into space. Given our own level of technology, could we detect such a signal from light-years away? If so, then maybe we can hear ET, too.

To read more, click here.