Illustration of the space debris orbiting Earth. Credit: ESA Aerospace engineers have to consider numerous factors when designing a spacecraft, but one that comes up more and more often is the need to design against micrometeoroids and orbital debris (MMOD). While most designers understand the threat, designing structural solutions capable of withstanding the hypervelocity impacts these undercontrolled pieces of material can cause can take a significant bite out of a mission's mass budget. A new paper from Binkal Kumar Sharma of the University of Bremen and Harshitha Baskar, an independent researcher, provides a detailed review of cutting-edge options for defending against those deadly particles. The study is published on the arXiv preprint server. To be clear, there are actually two distinct threats designers must look out for. One is from micrometeoroids—small rocks from space that have broken off a comet or asteroid and are the dominant threat at orbits lower than 270km and above 4800km.…