Cooler temperatures begin this week as a polar vortex brings much colder conditions with the chance of snow for Snowdonia, Ogwen Valley, North Wales on 22nd October 2018. The Ogwen Valley and Tryfan Mountain looking splendid in the Autumn sunrise. (Photo by DGDImages/Alamy Live News)

Wedges of an orange generate enough current and electrical juice – 3.5 volts – to power an LED. The fruit’s citric acid helps electrons flow from galvanized nails to copper wire in this 14-hour exposure. This image was published in September’s Visions of Earth, a trio of photos that appear in each issue of National Geographic. (Photo by Caleb Charland/National Geographic)

Bikini-clad women ski as they are led by a car during a performance on the frozen Yenisei River outside Krasnoyarsk, Siberia, Russia, March 20, 2016. The performance, entitled “Siberian Spring's Strings” and created with the participation of artist Vasily Slonov, marked the day of spring equinox (vernal equinox), according to organizers. (Photo by Ilya Naymushin/Reuters)

People watch a forest fire in Funchal, Madeira Island, Portugal, 09 August 2016. The fire has led to the evacuation of 400 people. Portugal remains on high alert as a wave of wildfires has swept the country with around 350 isolated fires affecting swathes of the countryside. (Photo by Gregório Cunha/EPA)

A Felix the Cat balloon and other parade floats and balloons are led down Broadway during the annual Macy's Thanksgiving Day Parade; ca. 1900s, Broadway, Manhattan, New York City, New York State, USA. (Photo by Underwood & Underwood/Corbis)

A South Korean diver wearing a little mermaid costume performs in a tank ahead of the “Chuseok” national holiday, at the Coex Aquarium in Seoul, South Korea, 26 August 2022. Chuseok is the autumn harvest celebration of the Lunar Calendar and is one of Korea's biggest traditional holiday, which falls on 10 Setpember this year. (Photo by Jeon Heon-Kyun/EPA/EFE)

This artist image released from Japan's airline All Nippon Airways (ANA) on April 17, 2015 shows ANA's Boeing 787-9 aircraft into the colors of R2-D2 robot of Star Wars. Japanese air carrier ANA will place the special colored jetliner in service in this autumn. (Photo by AFP Photo/All Nippon Airways)

Today is what is known as the equilux and it happens when day and night are equal and occurs a few days before the spring equinox, and a few days after the autumn equinox. What appears to be a floating leaf is actually a stray sticking to a wet car windshield in a park in Scaggsville, Maryland on September 25, 2024. Today sunrise was at 7:02am and sunset took place at 7:02pm. The green and orange colored leaf (about half for each color) seems to represent the transition from Summer to Fall. (Photo by Michael S. Williamson/The Washington Post)