In this photo taken Thursday January 17, 2013, sled dogs Poncho, left, and his blind brother Gonzo are hooked up for a run at the Muddy Paw Sled Dog Kennel, in Jefferson, N.H. Poncho has taken to helping his blind brother on regular runs. (Photo by Jim Cole/AP Photo)

The 26th annual National Geographic Traveler Photo Contest is now accepting submissions. Official categories include: “Travel Portraits”, “Outdoor Scenes”, “Sense of Place” and “Spontaneous Moments”. The contest is accepting entries until June 30. Photo: “Forest lights”. Aurora Borealis over the forest of the Pyhae Luosto National Park, Finland. (Photo and caption by Nicholas Roemmelt/National Geographic Traveler Photo Contest)

A member of the USA Knights team is seen wearing a face-like helmet shield during the International Medieval Combat championships at the castle of Belmonte, May 4, 2014, in Belmonte, Spain. The steel armor the knights wear can cost up to $10,000 and weigh 80 pounds. (Photo by Juan Naharro Gimenez/Getty Images)

Photographer Han Youngsoo captured the ordinary people of Korea as the country emerged from war into an age of prosperity. Han Youngsoo: Photographs of Seoul 1956–63 is at the International Center of Photography (ICP), Jersey City, New Jersey, until June 9, 2017. Here: Seoul, Korea. (Photo by Han Youngsoo/The Guardian)

“These Rajasthani sisters were sitting on the staircase inside their house relaxing and enjoy a cup of masala chai”. (Photo by Firdaus Hadzri/National Geographic Travel Photographer of the Year Contest)

A man poses for a picture in front of Christmas lights decoration at the Francisco Morazan square in San Salvador, El Salvador, December 22, 2020. (Photo by Jose Cabezas/Reuters)

An image captured by Jasmine Vink, the winner of the wildlife and animal category and overall winner in Australian Photography’s 2018 Photographer of the Year competition. (Photo by Jasmine Vink/Australia's 2018 Photographer of the Year by Panasonic)

Lord Roscoe the cat runs through the crocuses on the lawns at the National Trust's 17th-century Ham House and Garden in Richmond, London on Monday, March 6, 2023. In recent years more than 500,000 bulbs have been planted to create a spectacle for visitors and to attract bees, butterflies and other pollinating insects. (Photo by Kirsty O'Connor/PA Images via Getty Images)