ALT A spiral galaxy viewed from its side, featuring a giant halo of hot gas blowing out of its stellar disk. X-rays from Chandra and ESA’s XMM-Newton (purple and royal blue) trace hot gas driven out by supernovas and black holes and neutron stars pulling gas from their companions, while optical light (light blue, gold and white) from ground-based observer R. Jay GaBany showcases dense dust lanes. Edge-on views of galaxies allow astronomers to study how flat their stellar disks are and provide the clearest views of material located above or below the disk. Image Credit: X-ray: NASA/CXC/SAO; Optical: ©2011-2015 by R Jay GaBany, Cosmotography.com; Image Processing: NASA/CXC/SAO/L. Frattare