In January 1992, two cosmic objects forever changed our galaxy. For the first time, we had concrete evidence of extrasolar planets, or exoplanets, orbiting an alien star: two rocky worlds, whirling around a star 2,300 light-years away. Now, just over 30 years later, that number has exploded. This week, March 21 marked the hugely significant milestone of over 5,000 exoplanets confirmed. To be