A nurse shows a syringe with a dose of the COVID-19 vaccine to a citizen who is about to receive it during a vaccination day as part of the campaign in Mexico City at Pepsi Center WTC on May 25, 2021 in Mexico City, Mexico. According to the head of Govermnment, Claudia Sheinbaum, seven municipalities will start their campaign today which plans to apply the first dose to over 500,000 citizens between 50 and 59 years old. (Photo by Hector Vivas/Getty Images)

This artist's scoreboard displays a fictional game between Mars and Earth, with Mars in the lead. It refers to the success rate of sending missions to Mars, both as orbiters and landers. Of the previous 39 missions targeted for Mars from around the world, 15 have been successes and 24 failures. For baseball fans, that's a batting average of .385. The United States has had 13 successes out of 18 attempts, or a “batting average” of .722. NASA's Curiosity rover, set to land on the Red Planet the evening of Aug. 5, 2012 PDT (morning of Aug. 6 EDT), will mark the United States' 19th attempt to tackle the challenge of Mars, and the world's 40th attempt. (Image by NASA/JPL-Caltech)

A soldier poses with a Hythe Mk III Gun Camera during training activities at Ellington Field, Houston, Texas in April of 1918. The Mk III, built to match the size, handling, and weight of a Lewis Gun, was used to train aerial gunners, recording a photograph when the trigger was pulled, for later review, when an instructor could coach trainees on better aiming strategies. (Photo by Harry Kidd/WWI Army Signal Corps Photograph Collection via The Atlantic)

Inside the Afar Triangle in Ethiopia’s Danakil desert, camel caravans are used to carry salt. For centuries, the essential mineral has been mined by the Afar people, known for their ability to withstand extremes. The terrain is rugged, travelers are scarce and so are motor vehicles, where the average annual temperature is the highest in the world, and can rise to 122 degrees Fahrenheit, 50 degrees Celsius. (Photo by Ziv Koren/Polaris)

A riot policeman uses a baton to hit a rioting University of Nairobi student in Kenya's capital Nairobi, in this May 20, 2014 file photo. (Photo by Noor Khamis/Reuters)

People stand in front of an murals at Lodhi Art District in New Delhi on March 24, 2019. Visitors throng Lodhi colony which has murals by dozens of Indian and international artists. (Photo by Sajjad Hussain/AFP Photo)

Musafir, a pet monkey, eats sweets on a pavement in Kolkata, India, June 9, 2016. (Photo by Rupak De Chowdhuri/Reuters)

A horse is paraded during the Arabian Horse Festival at the Bait al-Arab in Kuwait City on February 5, 2022. (Photo by Yasser Al-Zayyat/AFP Photo)