Human beings are bad at many things, but we're particularly terrible at understanding probability in a rational way. We underestimate, overestimate and generally mess up probability. We'll try to fix it here, but we'll surely fail.

Small changes can have a big impact. But can a butterfly’s wingbeat in the Amazon really impact the weather halfway across the world? And where do small changes have no impact?

435: The Butterfly Effect Astronomy Cast 435: The Butterfly Effect by Fraser Cain & Dr. Pamela Gay

Once again, science fiction television and movies has let you down. They try to recreate what it might be like on an alien world, but surprise surprise, they mostly get it wrong. That’s because a truly alien world would be different in so many ways, it would blow your mind. Today we’ll help you figure out if you’re on a movie set, or you’ve actually crashlanded on an alien planet.

434: Am I On An Alien World? Astronomy Cast 434: Am I On An Alien World? by Fraser Cain & Dr. Pamela Gay

433: Volcanoes on Mars Astronomy Cast 433: Volcanoes on Mars by Fraser Cain & Dr. Pamela Gay

Mars is a world of extremes. This unassuming red world is home to the largest and tallest volcanoes in the entire Solar System. In fact, it’s not even a close contest, with Olympus Mons rising 22 km above the surrounding plains, more than twice as tall as Mount Everest. How did Mars get such big volcanoes, and how active is the planet today?

432: Geologic Ages of Mars – From Wet and Wild to Desolate Desert Astronomy Cast 432: Geologic Ages of Mars – From Wet and Wild to Desolate Desert by Fraser Cain & Dr. Pamela Gay

Today, Mars is a desolate wasteland, with dusty red rocks and sand stretching out to the horizon. But billions of years ago, it was a vastly different world. It was blue, with oceans, rivers, lakes, and maybe life? Let’s tell the story of geology on Mars, and we got from that world to the one we see today.

Enceladus and Europa are all the rage these days, but classic Mars is still a great place to search for life. In fact, ESA’s ExoMars is scanning the planet’s atmosphere for methane, evidence that there might be life there right now. Let’s talk about the search for life on the Red Planet.