Plutonium-239 doesn't have to be used in weapons, but after converting it to fuel, there aren't many other practical options.

Is it worth the convenience for a machine to recognize your face? Submit a selfie, and you don't need to carry a ticket into a concert, promises Moscow's NTechLab, which used face-scanning technology to let people into a electronic music festival this summer. Of course, the selfies, once submitted, stay with NTechLab, which is free to sell its face database and facial recognition tool to anyone, from concerts to police departments to authoritarian governments.

The Galaxy Note 7 was meant to serve as Samsung's best 5.7-inch, stylus-wielding smartphone. Introduced in August to great fanfare, the new Note device not only offered Samsung users an updated smartphone option, it also served as a way to tide over customers until the presumed Galaxy S8 in March 2017. At least that was the plan, until Samsung's Galaxy Note 7 began to catch fire while plugged in to charge. Now Samsung has chosen to cease production on the Note 7 line until further notice.

On October 2nd, in Irbil, Iraq, a drone flown by ISIS killed two Peshmerga, or Kurdish soldiers, and injured two French paratroopers, who were supporting Kurdish force, according to French newspaper Le Monde. The attack is possibly the first where a drone fitted with an improvised explosive device has inflicted casualties on troops from a Western nation.

From tracking migrating birds to monitoring changes in weather and climate, there are only so many data points a scientist can collect. To boost their reach, many researchers are reaching out to all of us, private citizens, to be citizen scientists, to accurately record observations and dramatically expand the impact of scientific studies. In Citizen Scientist: Searching for Heroes and Hope in an Age of Extinction, author Mary Ellen Hannibal blends reporting, research and memoir into an intimate look at this rapidly expanding field of exploration, how it reveals and protects the planet and its inhabitants, and how we can all get involved. You can read an excerpt of the book here. Below Hannibal shares her insights into citizen science for our latest Q+A for Nexus Media News.

There's little doubt that Australia and the US have an obesity problem. At the moment, over one-third of Americans are considered to be obese and the numbers continue to rise. Public health officials have been trying to figure out how to combat this growing concern yet there appears to be few answers.

We know that there are multitudes of exoplanets scattered throughout the universe, but to date the only planets that we have been able to take a picture of are in our own cozy solar system. That might be about to change with a new initiative launched today that aims to send a telescope into low Earth orbit to take a picture of the binary Alpha Centauri system, which houses the two closest sun-like stars to our solar system

“The first true internal combustion engine was undoubtedly the cannon,” Popular Science declared in October 1904, citing the work of Christiaan Huygens in the 1680s, before plotting a history of the engine through the gas engines of the 1860s.

Last month, Popular Science discussed the state of gut microbiome research and the often overgeneralized claims of many probiotics. As we concluded, the field is still in its infancy and one of the main challenges to creating effective prescription probiotics is that it's extremely difficult to culture a lasting population of specific bacteria in the gut. But in a paper out last week in the journal Cell Host and Microbe, researchers at the University of Alberta showed that they were able to culture a strain of bacteria in the gut for at least six months. This success, while small, may help to bring us one step closer to creating effective prescription probiotics.

Adding more cars to the roads makes traveling by car a worse experience for everyone. There are many ways for cities to get around this: improved transit systems, support for carpooling, and bike paths are just the start, but what about a city that already has existing waterways? Isn't there something they could do with rivers or canals instead?

Its no news that bumble bees, or the "humble-bee," as Charles Darwin first deemed them in Origins of the Species, are in danger. The U.S. Fish and Wildlife Service proposed putting the rusty-patched variety of these fuzzy buzzers on the endangered species list last month, after years of incredibly rapid population decline.

Sediment-rich floodwaters pour from rivers in North and South Carolina.

Wondering where to watch the presidential debates as Trump and Clinton finally face off? We've got good news: it'll be hard to miss them. Pretty much every social media app, network website, and news channel in broadcast and cable will have live coverage of the debates, starting next week.

This afternoon, the United States Department of Homeland Security and the Office of the Director of National Intelligence released a statement claiming that the Russian Government “directed the recent compromises of e-mails from US persons and institutions, including from US political organizations.”

The RQ-4 Global Hawk is built for watching disasters unfold. The high-altitude, long endurance drone can fly for over 34 hours and reach an altitude of 60,000 feet above ground. Most of these expensive, private-jet-sized drones fly for the Air Force, where they watch battlefields in places like Afghanistan and Iraq, finding targets and coordinating troops below. NASA also flies one, for scientific research, and last night they used it to drop sensors into Hurricane Matthew.