The Associated Press recently re-transmitted a collection of images from the Syrian conflict. It remains an incredibly dangerous situation for working journalists who document the ongoing conflict and the conditions of those living in constant danger and with constant risk. Many continue to die for their beliefs, hoping that peace will come to their country eventually. The images that follow are storytelling, intimate and worth seeing again and again. -- Paula Nelson ( 32 photos total)

Scientists in both the United States and Morocco are studying what it would be like for human beings to live on Mars. Reuters photographer Jim Urquhart spent time in the Utah desert at the Mars Desert Research Station observing a crew simulate what conditions would be like on the red planet. Researchers with the Austrian Space Forum in partnership with the Ibn Battuta Center spent time in the northern Sahara conducting experiments in engineering, planetary surface operations, astrobiology, and geophysics. -- Lloyd Young ( 27 photos total)

Charlie Haughey was drafted into the US Army in October of 1967. He was 24, and had been in college in Michigan before running out of money and quitting school to work in a sheet metal factory. The draft notice meant that he was to serve a tour of duty in Vietnam, designated a rifleman, the basic field position in the Army. After 63 days in Vietnam, he was made a photographer, shooting photographs for the Army and US newspapers, with these instructions from the Colonel: “You are not a combat photographer. This is a morale operation. If I see pictures of my guys in papers, doing their jobs with honor, then you can do what you like in Vietnam.” He shot nearly 2,000 images between March 1968 and May 1969 before taking the negatives home. And there they sat, out of sight, but not out of mind, for 45 years, until a chance meeting brought them out of dormancy and into a digital scanner. At first, it was very difficult for Haughey to view the images and talk about them, especially not knowing the fates of many of the subjects of his photos. When the digitization hit 1,700 negative scans, Haughey put them on a slideshow and viewed them all at once, and didn’t sleep for three days after. He’s slowly getting better at dealing with the emotional impact of seeing the images for the first time in decades. A team of volunteers has worked with Haughey to plan a 28-image show, titled A Weather Walked In, which opens April 5th in the ADX art gallery in Portland, Oregon. The difficulty of keeping notes in a war zone along with the passage of decades has faded the details behind many of the images, and the captions reflect this fact, with many shots of unknown people in forgotten locations at unspecified times. It is hoped that publication of the pictures can yield more information. More images from the collection will be released as the project progresses. You can follow the progress on facebook and Tumblr. Thanks to Chieu Hoi project volunteer Kris Regentin for preparing much of this introduction and the accompanying captions. -- Lane Turner (46 photos total)

The Smithsonian magazine's 10th annual photo contest's 50 finalists have been chosen, but there's still time for you to vote for the Readers Choice winner! This year's competition has drawn over 37,600 entries from photographers in 112 countries around the world. Editors will choose a Grand Prize Winner and the winners in each of five categories which include The Natural World, Americana, People, Travel and Altered Images. Voting will be open through March 29, 2013. -- Paula Nelson ( 22 photos total)

Pope Francis officially became the 266th leader of the Roman Catholic Church's 1.2 billion worldwide followers yesterday during his formal installation Mass in St. Peter's Square. Formally known as Cardinal Jorge Mario Bergoglio, the 76-year-old Argentinean is the first non-European pope in more than 1,200 years and the first from South America. During the Mass, which was attended by an estimated 150,000 to 200,000 people, Francis pledged to serve ‘‘the poorest, the weakest, the least important,’’ striking the same tones of humility that have marked the days since his election. -- Lloyd Young ( 24 photos total)

Over twenty years ago the United Nations recognized March 22 as the first World Water Day. This year's theme is water cooperation. As the following photographs show, the need for cooperation on this precious resource is great, as some enjoy plenty while others suffer drought. Collected here are images of water and its many uses as we approach the annual World Water Day. -- Lane Turner (36 photos total)

New Zealand photographer, Amos Chapple, made three visits to the Islamic Republic of Iran between December 2011 and January 2013. Chapple "was amazed by the difference in western perceptions of the country and what I saw on the ground…" He goes on to say that every traveller he met inside Iran had the same sense of surprise. The government continues its anti-western campaign, but Chapple explains what was once a popular sentiment has long since faded with Iranians. Chapple describes this as a "constant embarrassment for ordinary Iranians. In the time I spent there, I never received anything but goodwill and decency, which stands in clear contrast to my experience in other middle eastern countries." A sampling of Chapple's images are featured in this post. -- Paula Nelson (The captions were provided by the photographer. All images are copyrighted.)( 25 photos total)

The 41st Iditarod Trail Sled Dog Race came to an end yesterday in Nome, Alaska. Mitch Seavey, 53, with his team of ten dogs, became the oldest musher ever to win the 1,000-mile race across the Alaskan wilderness in just over 9 days, 7 hours. Last year his son, Dallas, became he youngest winner at 25. His winnings included $50,000 and a new truck. The race is a remaking of the freight route to Nome which pays tribute to the role sled dogs played in the settlement of Alaska. -- Lloyd Young ( 31 photos total)

The shoreline -- of the sea, lakes, and rivers -- is a dynamic interface of civilization and the natural world. It exerts a powerful draw on us. That transition space holds beauty and carries risk, the zone where we at once embrace and battle the environment in which we exist. The shoreline provides food, recreation, breeding grounds, commerce, peace, and even primal fear. Two thirds of the world's largest cities lie in low-elevation coastal areas, vulnerable to sea rise even as population trends show us increasingly dwelling in urban areas. Gathered here are images exploring our attraction to the water's edge. -- Lane Turner (46 photos total)

Millions of Kenyans poured into polling stations on March 4, to cast their ballots in a crucial presidential election. Voter turnout was tremendous, starting hours before dawn, with lines of voters stretching nearly a mile long. Some voters waited nine hours on their feet in the hot sun to cast their ballot. The presidential election was the first since 2007 which ushered in months of tribal violence that killed more than 1,000 people and displaced 600,000 from their homes. Election officials in Kenya are now counting ballots by hand after abandoning the electronic tabulation system. With about a quarter of votes counted, Uhuru Kenyatta, the scion of a political family who has been accused by the International Criminal Court of financing death squads, held a commanding lead of 55 percent to 41 percent over the second-place candidate, Raila Odinga, Kenya's prime minister. Election observers cautioned that the preliminary results might not be representative of the countrywide vote. Kenyans await the results. -- Paula Nelson ( 40 photos total)

For this edition of our look at daily life we share images from Iraq, Israel, Burma, Germany, China, Pakistan, Serbia and a few others from around the world. -- Lloyd Young ( 37 photos total)

As professional and amateur cameras reveal more of the world at an increasingly rapid pace, the field of photojournalism is becoming a harder place to make a living. Yet many young photographers are pursuing careers as visual storytellers, despite a market in transition. Some study the craft at universities, others carve their own path. While building their portfolios, they have the luxury of time to explore intimate stories about relevant issues and develop a personal vision. Without the pressures of the 24-hour news cycle, these photographers are learning to make images that shout rather than whisper. Covering issues near and far, often out-of-pocket and on their own time, they posses a deep affection for people and a common goal of building a better understanding of our world. The future of photojournalism may be uncertain, but this generation of photographers will have a hand in writing the new rulebook. The following are images from students of photojournalism and photographers aged 25 and under. The featured images are peak moments captured through eager eyes, personal visions, or intimate glimpses into long-term projects about topics that matter to the photographers and their community. -- Tamir Kalifa [ Editor's note: Tamir Kalifa was the Boston Globe's summer photography intern in 2012. Offered the opportunity to create a Big Picture post, he chose the theme of photojournalists under 25. His search took him to a few international photography schools, the College Photographer of the Year contest, and the Eddie Adams Workshop Facebook group, among other sources. The result, while yielding some fantastic pictures, is as yet incomplete. I'd like to use the occasion of this post to solicit photographs for another "photojournalists under 25" post, hopefully attracting more photographers outside Europe and North America. If you're a photojournalist under 25 and want to display your work on The Big Picture, post your picture on our Facebook page, along with full caption information. We'll gather the best of the submissions and publish the post sometime later this year. For those over 25 who'd like to contribute to The Big Picture, we'll announce a theme soon for a future readers-only post. -- Lane Turner ] (40 photos total)

“Searching for the Seventies” takes a new look at the 1970s using remarkable color photographs taken for a Federal photography project called Project DOCUMERICA (1971-1977). Created by the Environmental Protection Agency (EPA), DOCUMERICA was born out of the decade’s environmental awakening, producing striking photographs of many of that era’s environmental problems and achievements. Drawing its inspiration from the depression era Farm Security Administration photography project, project photographers created a portrait of America in the early-and-mid-1970s. They documented small Midwestern towns, barrios in the Southwest, and coal mining communities in Appalachia. Their assignments were as varied as African American life in Chicago, urban renewal in Kansas City, commuters in Washington, DC, and migrant farm workers in Colorado. The exhibit, featuring 90 images from the project opens March 8, 2013 at the National Archives in Washington D.C. It runs through September 8, 2013. What follows is a small sampling of the collection digitized by the National Archives. -- Paula Nelson (NOTE: Captions were provided.)( 30 photos total)