From left to right (1-5):
- Jagged Horizon on Rosetta Destination Comet, 2014-11-11 [ESA/Rosetta/NAVCAM]
- Captive Balloon and Ferris Wheel, World’s Columbian Exposition, Chicago, c. 1893, Library of Congress
- A powerful electrical storm created an eerie tapestry of light in the skies near Complex 39A in the hours preceding the launch of STS-8, 1983, [NASA]
- Arroyo Seco Parkway, Figueroa Street Viaduct, Spanning Los Angeles River, Los Angeles, Los Angeles County, California, Historic American Engineering Record (Brian Grogan, photographer), Library of Congress
- Mercury Through Time, 2008-10-10 [NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington]