As we learn more and more about our solar system from NASA’s robotic and human explorers, we can’t help but also seek to understand what lies beyond. Our solar system exists in a sea of countless solar systems across billions of galaxies. While we can’t yet visit these distant worlds with robotic or human-led missions, we are beginning to get a better picture of them thanks to powerful telescopes and remote-sensing techniques that allow us to analyze their chemical signatures and more. Scientists are even discovering worlds that may be very similar to our own.