The name “Mercator” is boldly displayed on the nose of the Pegasus XL rocket. The rocket is the launch vehicle for NASA’s Interstellar Boundary Explorer, or IBEX, spacecraft. The IBEX satellite will make the first map of the boundary between the Solar System and interstellar space. The name Mercator was chosen in honor of Gerardus Mercator, the Flemish cartographer (or map maker). In addition to the many maps that he made, he also invented a technique to create terrestrial and celestial globes out of paper mache, allowing for greater production than the carved wooden or brass globes that were previously used. IBEX is targeted for launch from the Kwajalein Atoll, a part of the Marshall Islands in the Pacific Ocean, on Oct. 19. IBEX will be launched aboard the Pegasus rocket dropped from under the wing of an L-1011 aircraft flying over the Pacific Ocean. The Pegasus will carry the spacecraft approximately 130 miles above Earth and place it in orbit. Photo credit: NASA/R. Bledsoe, VAFB