Planetary scientists announced some big news this week about our next-door neighbor, Venus. For the first time, they had found direct evidence that Venus has active, ongoing volcanic activity. "It's a big deal," says Dr. Martha Gilmore, a planetary geologist at Wesleyan College. "It's a big deal in that there are no other planets, actually, where we've seen active volcanism." (Moons don't count - sorry Io!) What makes that fact so striking is how inhospitable a place Venus is now – crushing pressure, a toxic atmosphere and a surface temperature around 850 degrees Fahrenheit. So, what happened? How did Earth and its closest sibling diverge so sharply? On today's episode, Martha talks with scientist in residence Regina G. Barber about what studying Venus can tell us about the past and the future of our own planet.