Robot vacuums are great at keeping your floors clean, but there are a few areas they fall down on the job — stairs being one. Another is chairs and stools. You know the scenario: You have a row of stools at a kitchen table, or chairs tucked under a dining table, and the robovac just
About 12 billion years ago, a dwarf galaxy known as LKH collided with a young Milky Way and merged with it. This artist’s concept portrays that collision. NASA’s Hubble Space Telescope uncovered definitive evidence of this collision by studying globular star clusters. Illustration: NASA, ESA, Joseph Olmsted (STScI) Our home galaxy, the Milky Way, grew
