The story of the past 35 years in astronomy has been discovering just how massive our Solar System really is. Although these discoveries in aggregate is what eventually doomed Pluto to a planetary demotion (Eris is just a sliver smaller than pluto), Sedna was particularly eye-catching. Oh, and astronomers discovered another interesting aspect about Sedna: Its closest approach was just one human lifetime away. “Due to the limitations of traditional methods, innovative propulsion systems are crucial to reach distant targets like Sedna,” the authors write. Sending a spacecraft to Sedna would be one of the greatest challenges in the history of spaceflight, but a rewarding one.