Are we alone in the universe? Probably not. Scientists are hard at work looking for signs of life here in our solar system and beyond. But what will we say to those extraterrestrials when we find them?

Author and journalist Daniel Oberhaus delves into the efforts to talk with alien civilizations in his new book “Extraterrestrial Languages.” We’ll talk with Oberhaus about the attempts to speak with other civilizations in the universe and why many scientists think it’s a bad idea to reach out to them first.

Then, as we continue to venture into our solar system, there’s a greater need to keep it clean. On this week’s “I’d Like to Know” segment, we’ll chat with planetary scientist from the University of Central Florida about keeping our dirty Earth-germs off other planets and moons — and why the search for life depends on it.