The news of Osama bin Laden's killing was met with cautious excitement by many men from Bravo Company, 1st Battalion 5th Marines in Helmand River Valley — allegedly one of the most dangerous regions of Afghanistan.

The event is a "notch in the belt," one Marine told NPR photographer David Gilkey, who is embedded with the group. The reigning sentiment was that this is positive, but that the fight goes on:

Enlarge David Gilkey/NPR

A Bravo Company Marine from Camp Pendleton, Calif., patrols in the Helmand River Valley in southern Afghanistan on Monday.

David Gilkey/NPR

A Bravo Company Marine from Camp Pendleton, Calif., patrols in the Helmand River Valley in southern Afghanistan on Monday.

Here's what some of the Bravo Company marines had to say about the killing of bin Laden:

"We're still here in Afghanistan, Sangin is still very hostile, especially where we're at here, the enemy is still going to fight us, and we have to maintain our composure — not get complacent. Just because we took out the head honcho doesn't mean these guys are gonna throw up their arms and be done with it."

"There's still a lot of work that needs to get done here. It's a huge step in the right direction ... but we still need to finish our mission. ..."

"There's always gonna be insurgency, it's never gonna end. ... This fight's definitely gonna be a hard one to win, but I don't think it's impossible."

"What happens tomorrow? We're gonna just do the same thing. We're gonna wake up and keep doing what we're doing every single day until we're out of here. Because we've got a job here. We've got a mission to complete. And that's what we're gonna do."

"I think that everyone's gonna be real happy about the fact that it's one bad man that can't hurt anybody else, but ... It's one more day. ... It didn't end the war for us. ... I think everybody's just gotta stay focused on what they're doing."

Jonas Bendiksen/National Geographic

Photographer Jonas Bendiksen made three separate trips to Bangladesh last year to document the wet season and the ways that rising waters are altering Bangladeshi life. National Geographic's May issue shows the impact of flooding in a densely-populated, low-lying country barraged by seasonal monsoons and cyclones, and situated in the Ganges Delta — the world's largest delta.

The photos portray an adaptability and resilience of the Bangladeshi people — who don't seem to ask if there will be floods during the wet season, but when and how often. The photos also visualize what other coastal populations could face with rising sea-levels.

On the phone, Bendiksen explains that floods in Bangladesh aren't always viewed as natural disasters. Some people will move 20 to 30 times in their lifetime due to flooding, so their homes and lives are mobile. Some convert flooded rice paddies into shrimp farms or floating gardens. Children are taught in mobile floating schools aboard boats; they invent new ways to survive.

Bendiksen asserts that "their solutions are not global fixes," but he says, "their approach gives me hope and inspiration."

Here it is:

Enlarge Matt Dunham/AP

While millions of onlookers enjoyed the newlyweds' kiss at Buckingham Palace, a certain someone (left) seemed to be not pleased. (AP Photo/Matt Dunham)

Matt Dunham/AP

While millions of onlookers enjoyed the newlyweds' kiss at Buckingham Palace, a certain someone (left) seemed to be not pleased. (AP Photo/Matt Dunham)

Mahesh Shantaram

Mahesh Shantaram is a wedding photographer based in Bangalore, India. I asked him what he would do if he were in the shoes of Hugo Burnand, the official royal wedding photographer. "I don't see myself as a successful photographer in the West," he wrote in an email. "It's all too perfect and colorless."

Shantaram's photo series, Matrimania, shows just how colorful weddings are in India — where you don't have to be royal to have a big celebration. "We in India take our weddings very seriously," he writes on his site. The series was a finalist in the Sony World Photography Awards this year.

Mahesh Shantaram

Billboards serve as wedding invitations in the town of Tamil Nadu.

Though it may seem extreme to turn Westminster Abbey into an enchanted forest, Shantaram probably isn't fazed. One of the more elaborate weddings he has seen, for example, was in a small town in Tamil Nadu. Billboards were used for wedding invitations, he says, and a castle was specially built to accommodate the 11,000 guests. The reception was themed Alice in Wonderland, a "more intimate affair" of 8,000 guests.

Why the fascination with weddings?

"I find them to be fascinating metaphors of my country's penchant for order and chaos, color and noise," Shantaram writes, "and the peculiar sense of taste and design or the lack thereof."

In India, too, people are preparing for tomorrow's royal wedding. Some are planning to leave work early to watch the event live, says Shantaram. "I thought that kind of fervour was reserved for World Cup Cricket alone!"

Enlarge Angeliki Kapoglou /flickr

Mission to Mars

Angeliki Kapoglou /flickr

Mission to Mars

Angeliki Kapoglou, who took this photo, was selected to serve as a member of an international crew on the Mars Desert Research Station (MDRS), which simulates the environment on Mars in the Utah desert to develop knowledge needed to prepare for human exploration on the Red Planet. She writes:

"Unlike researchers in typical laboratory facilities ... crew members who live and work at MDRS are forced into a unique mindset, as if they themselves were exploring the surface of Mars and living in an early Mars habitat.

"For example we cannot go outside unless we are wearing our simulated spacesuits. ... We also have to eat dehydrated food and have very limited water usage. Only through such firsthand experience can we develop the knowledge that will prove critical for human safety and productivity on the surface of Mars."

You can see more photos from the series on Flickr.

"Your Photo Of The Day" is curated from our Flickr group. Submit your photos here.

You've seen ants. Thousands of them. And most of the time, you've seen them in colonies, living as a group. But have you seen them float as a group? Apparently a single fire ant will struggle in water, but a cluster of them can bob happily for months. A new study has used time lapse photography to figure out why — and how — that is.

PNAS

The above fire ants, or Solenopsis invicta, have evolved so remarkably, that they can self-assemble into structural tools utilized by the entire colony. They have been known to build ladders, chains and walls — out of themselves — that ensure their colony remains intact.

To survive a flood, for example, they can link in a matter of seconds by mandibles, tarsal claws, and adhesive pads on their feet — to form, in essence, a raft. In short: by joining this way the ants are able to decrease their mean density as a whole and become a buoyant raft; if left alone they would sink.

PNAS

Sightings of ant rafts were reported following flooding from Hurricane Katrina. These findings may contribute to future technologies for floating devices and waterproof materials.

Members Only jackets and crimped hair have gone out of style, but some things will never change. These photos, now three decades old, show a familiar scene: die-hard royal fans decked out in garish wedding swag, waiting for the marriage of Lady Diana Spencer to Charles, Prince of Wales. Though many in England may not give a toss about Friday's events this year, others are already camped outside Westminster Abbey. More throwback photos of the '80s wedding are at life.com.

Robyn Hasty has a notion to travel the country "documenting the collapse of the American economy," as she writes on her website. For that sort of endeavor, you need two obvious things: a car and a camera. She has the car part down. But there are two minor setbacks: She actually doesn't consider herself a photographer. And she can't exactly jump out of the car and take a snapshot with this setup:

Enlarge Robyn Hasty

Hasty's camera setup

Robyn Hasty

Hasty's camera setup

For Hasty, inconvenience is kind of the point. Homeland, her project, is not a mad-dash documentary, nor is it really journalistic. It's a slow investigation of alternative communities throughout the U.S. So far, word-of-mouth tips and referrals have taken her to New Orleans, Dallas, Little Rock ... in a Volkswagon hatchback, 1890s-era wet-plate camera in tow.

Her focus is on far-flung, often off-the-grid locations, where individuals and small communities are getting by in their own unique ways: urban farmers, squatters, metalworkers building boats to float down the Ganges (see slideshow). Some of them may have emerged as a result of economic setback; but many of them have been off the grid as long as there's been a grid.

Tod Seelie

Hasty takes a photograph with her wet-plate camera

She has no pretensions of being an objective observer. "I've been part of grass-roots movements," she said on the phone. "There's something very intimate about this essay. I'm not an outsider; it's coming from being inside of it, and from personal interactions." Hasty herself is part of a small art collective; The Miss Rockaway Armada, as it's called, has built rafts from trash and floated down the Mississippi. This summer, they are being commissioned to do work in Philadelphia.

On the phone she rattled off a few travel tales — of CouchSurfing and automotive break-down. Some portraits from her most recent road trip, funded by a Kickstarter campaign, include D.J. Rusty Lazer, an activist at the forefront of New Orleans' hip-hop sound known as "bounce." There's Angeliska, who hosts arts events in Austin, Texas. And there are people who want to keep their names and locations anonymous.

Antique medium, hard-to-find communities: In short, it's just one of those unique projects you don't see very often.

Enlarge Tim Hetherington

Award-winning photojournalist Tim Hetherington (right) known for his work in war zones, died Wednesday in the Libyan city of Misrata when he was hit by a mortar round. He is pictured here with Sebastian Junger, his co-director of the film Restrepo, which was nominated for the best-documentary Oscar this year.

Tim Hetherington

Award-winning photojournalist Tim Hetherington (right) known for his work in war zones, died Wednesday in the Libyan city of Misrata when he was hit by a mortar round. He is pictured here with Sebastian Junger, his co-director of the film Restrepo, which was nominated for the best-documentary Oscar this year.

Joao Silva. Lynsey Addario. Tyler Hicks. Tim Hetherington. Chris Hondros: the names of photojournalists grievously wounded, kidnapped or killed in the line of duty since October 2010. The names and casualties of journalists harmed during conflicts seem to be mounting, leaving many of us who knew them or who have worked with them or - even those a few steps more removed - feeling a bit more vulnerable.

Nearly all journalists in conflict areas, or areas of disaster, take risks. Photojournalists, I think, are the biggest risk-takers for the cause because they must be more proximate, and the lens attracts attention.

If you knew the cause would take a limb or your life, or leave you beaten or raped, would you do it?

Phil Robertson, a New York based writer, has been close to Chris Hondros since they covered Afghanistan together beginning in 2002. As he told me today, "Conflict is a meat grinder and it destroys people's lives. We've seen way, way too many people get killed or injured, but this is OUR part of the war. It makes me realize more and more what the local civilians go through and how they feel."

I agree. And not only them, but the many local journalists who work for foreign organizations – like NPR. War is a terrible, uncertain, lethal condition. There will be other Misratas and Fallujahs and Korengal Valleys. I think the legacy, the honor, is to remember the people who put faces and feelings and emotions in front of us from those places, and reflect that there have always been stories, songs, and images of war and disaster. Perhaps their details blend over time, but we would not have the details except for those brave enough to gather them.

Getty Images

Photojournalist Chris Hondros poses with a a former Liberian government soldier, at his home in Monrovia, Liberia, in 2005. Hondros' picture of Duo jumping into the air in exultation during a battle with rebel forces in 2003 was distributed around the world. Hondros was killed April 20 in Misrata, Libya.

Robertson is writing a book at home now, in New York. He's the father of a toddler. But he has certainly taken risks and is thinking of Chris Hondros today. They shared rides in Afghanistan and a terrifying open-air truck ride in Fallujah.

And he and Hondros shared another ride. "He drove my wife and me and our new baby home from the hospital the day after our daughter, Zaina, was born in 2009," he said. "We were together on the most terrifying and beautiful days I have ever known."

Jacki Lyden is a correspondent and host for NPR.

Getty Images via AP

Getty Images photographer Chris Hondros stands in front of a burning building while on assignment on April 18, in Misrata, Libya. Hondros was killed in Misrata on April 20.

Photojournalists Chris Hondros and Tim Hetherington were killed by a mortar round in Misrata, Libya, on April 20. Fellow photographers Guy Martin and Michael Christopher Brown were also injured. Photojournalist Andrea Bruce shares her memories of Hondros.

People may not understand life in Iraq or Libya, but most know what its like to hurt. Or to lose someone they love. Crossing the language and cultural barriers of the world, photos point out the similarities of human nature. We have a visceral reaction when we see a little girl cry because her parents were shot in front of her. They are not just numbers or names. They are people. We want to reach inside the frame and help her.

This is what one of Chris Hondros' most unforgettable images from Iraq did for us. It shows a reality that was often reported, but rarely seen.

Chris Hondros/Getty Images

Samar Hassan, 5, screams after her parents were killed by U.S. soldiers with the 25th Infantry Division in a shooting in Tal Afar, Iraq, on Jan. 18, 2005. The troops fired on the Hassan family car when it unwittingly approached them during a patrol in the tense northern Iraqi town.

Chris understood the power of photography as much as most governments do. The first thing banned in countries of conflict, the first thing targeted, are cameras. But Chris had an unflinching desire to tell the truth and an uncompromising need make people see the problems of the world.

He always remained strong. Unapologetic.

He went to great lengths to provide anyone who asked with all the advice needed to do this job safely and intelligently. Or, make you a mixed CD of classical music when you were down. Or, take the time to write you a two-page, well-researched email if he disagreed with you.

Chris was the glue of our photojournalism community — a community that has had a rough year. Many colleagues have been injured, kidnapped and killed. The void left by his, and Tim's, death will not only be a blow to news organizations and all of us who knew and admired them, but also to the people who live in Misrata — who are also being killed — with few people left to give them a voice.

Without Chris, Tim, and other photojournalists like them, the truth about the horrors of war can easily be hidden. Dismissed. Accepted.

Andrea Bruce is a freelance photojournalist based in Afghanistan and Mexico who focuses on war and its aftermath. She has worked primarily in the Middle East and Asia for the past 10 years and is represented by the VII Network.

Enlarge Michael Fritz/Alfred Wegener Institute

A scientist stands in front of an ice-rich permafrost exposure in the coastal zone of Herschel Island, Yukon Territory, Canada. Ice in the permafrost is melting, contributing to rapid erosion.

Michael Fritz/Alfred Wegener Institute

A scientist stands in front of an ice-rich permafrost exposure in the coastal zone of Herschel Island, Yukon Territory, Canada. Ice in the permafrost is melting, contributing to rapid erosion.

Two-thirds of the Arctic coastline is made of permafrost — an environment that is very sensitive to warming temperatures. A new report says erosion is causing these coastline regions to recede by an average of 1.5 feet per year.

Unlike rock shoreline, permafrost loses its structure when it warms above freezing. "Surface air temperatures have reached record levels over the past decade," the report from an international consortium found. Combine this with weakened permafrost and there's a recipe for erosion.

Enlarge Hugues Lantuit/Alfred Wegener Institute

Large slumps of coastal land are caused by the thawing and erosion of ice-rich permafrost. As a result, large quantities of sediment are introduced into the coastal ecosystem, which alters the food web.

Hugues Lantuit/Alfred Wegener Institute

Large slumps of coastal land are caused by the thawing and erosion of ice-rich permafrost. As a result, large quantities of sediment are introduced into the coastal ecosystem, which alters the food web.

Heightened temperatures have also melted sea ice; with this gone, wind can whip up stronger waves that are able to erode the softened Arctic coastline.

Researchers studied more than 62,000 miles of Arctic coast and analyzed climate data. Northwestern Canada and Northeastern Russia showed the largest changes: Coastlines there have receded by as much as 25 feet per year. Researchers say these changes will have a major impact on arctic ecosystems.

There's a map of the affected areas here.

If you're reading this you're clearly not taking part in Digital Detox Week, aka Screen-Free Week, which begins today. The initiative promoting more face time and less screen time is the latest incarnation of what, until a few years ago, was called TV-Turnoff Week.

Berlin-based photographer Stephan Tillmans knows a thing or two about turning off televisions — it's how he makes his art. Luminant Point Arrays is a series of photos of old tube televisions taken at the very moment they are switched off.

Each of these images is from a different TV, but according to Tillmans it's also the length of exposure, timing, and time the TV has been running before the photo that accounts for the difference in results. Each image takes a lot of tries, because he's using good old-fashioned trial and error to get the shot.

"I stand between the TV and the camera with one finger on the on/off switch and one finger on the shutter release," he writes in an e-mail. "With some televisions it took about 800 pictures to get THE picture." No wonder he's working with a digital camera.

But then again you shouldn't care. Because you shouldn't be reading this. You should be knitting while climbing a tree or something.