Clearing skies await a tripod-toting photographer looking for a spot to capture the early-morning light at Portland Head Light, Thursday, January 17, 2013, in Cape Elizabeth, Maine. (Photo by Robert F. Bukaty/AP Photo)

The Northern Lights glow green in a spectacular light show above a field of trees frozen solid with snow. (Photo by Jaak Sarv/Solent News & Photo Agency)

“NASA's Pathfinder, Pathfinder Plus, Centurion and Helios Prototype were an evolutionary series of solar- and fuel-cell-system-powered unmanned aerial vehicles. AeroVironment, Inc. developed the vehicles under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program. They were built to develop the technologies that would allow long-term, high-altitude aircraft to serve as “atmospheric satellites”, to perform atmospheric research tasks as well as serve as communications platforms”. – Wikipedia

Photo: The solar-electric Helios Prototype flying wing is flies over the Hawaiian islands of Niihau and Lehua during the first solar-powered test flight July 14, 2001 from the U.S. Navy's Pacific Missile Range Facility on Kauai, HI. The 18-hour flight was a functional checkout of the aircraft's systems and performance in preparation for an attempt to reach sustained flight at 100,000 feet altitude later in the summer. (Photo Courtesy of NASA/Getty Images)

Hindu devotees light “Diyas” (earthen lamps) on a Rangoli, a framework of decorated pattern, as part of Diwali festivities in a temple premises in Dhaka, Bangladesh on November 12, 2023. The festival takes place every year in accordance with the Hindu lunar calendar. The word “Diwali” is derived from the Sanskrit word “Deepavali”, meaning series of lighted lamps; hence, it is also known as the festival of lights. Diwali is typically celebrated by socializing and exchanging gifts with family and friends. Many light oil lamps or candles to symbolize a victory of light over darkness, and fireworks are set off as part of the celebrations. (Photo by Joy Saha/Rex Features/Shutterstock)

“These eerily stunning images taken using infrared lighting reveal the landscapes of Iceland in all their natural glory. Andy Lee, 45, uses a special technique which blocks out light from some visible wavelengths and picks up light from others invisible to the naked eye”. – Caters News. Photo: Location: Kirkjufell. These eerily stunning images taken using infrared lighting reveal the landscapes of Iceland in all their natural glory. (Photo by Andy Lee/Caters News)

A chimpanzee looks in the direction of a camera at the Gut Aiderbichl Sanctuary for Traumatized Chimpanzees and other Primates in Gaenserndorf, near Vienna, 17 September 2018. 34 former laboratory chimpanzees of former Austrian pharmaceutical company Immuno AG spend their lives at the Gut Aiderbichl Sanctuary for Traumatized Chimpanzees and other Primates since 2009. (Photo by Christian Bruna/EPA/EFE)

A small section of the expanding remains of the Veil Nebula, a massive star that exploded about 8,000 years ago. The entire nebula is 110 light-years across, covering six full moons on the sky as seen from Earth, and resides about 2,100 light-years away in the constellation Cygnus, the Swan. (Photo by Reuters/NASA/ESA/Hubble)

A house and garden is illuminated ahead of Christmas in Olching near Munich December 11, 2014. The house is decorated with more than 30,000 lights. Every year hundreds of houses across Germany are decorated by their owners with lights ahead of Christmas. (Photo by Michaela Rehle/Reuters)