President Barack Obama challenged world leaders to join the United States in fighting global warming. Watch the entire 10-minute speech here.

Forty years after the first World Environment Day, and 20 years after the original 'Earth Summit,' Brazil is still a flashpoint for environmental politics.

As world leaders fly into Rio de Janeiro for Rio+20, thousands of people from indigenous tribes, environmental groups, unions and religious organizations gather

Discussions about the Russian meteor explosion and Earth's encounter with asteroid 2012 DA14 were high on the Feb. 15 agenda of a UN meeting.

The United Nations shares "ONE Life," a new song and music video highlighting the severity of climate change.

Each day, the average American throws away enough food to keep another person from going hungry.

Annual Koch Institute exhibition explores the thought-provoking and stunning visuals behind life sciences and biomedical research at MIT.

Dozens of massive president heads sit in a field in Virginia, waiting for a new home in a museum.

As polar bears struggle to survive in the fast-changing Arctic, MNN presents a tribute to the animals' legendary power, precocity and perseverance.

The conservation nonprofit Polar Bears International will use the 360-degree panoramas for educational outreach and scientific research.

This real-time aurora video may not seem amazing at first, but that quickly changes at the 1:52 mark.

Video: Historical films and field work reveal more about endangered Native American language.

Video: Is a trip to the 3-D movies making you sick?

Video: A Florida marine ecologist narrows down the spread of the first lobster virus.

Columbia researcher examines how ultrasound could become part of a comprehensive treatment for various degenerative brain diseases.

Find out what wood ducks are revealing about threats to our fine feathered friends.

Eavesdropping on mice for clues about how humans process sound.

Team at Seattle university is creating largest 3-D reconstruction that anyone has ever attempted, rebuilding the world one pixel at a time.

Your avatar may be just a virtual identity, but it can also affect how you are in the real world.

Babies are oriented towards pro-social individuals. They prefer interacting with a pro-social individual over an anti-social individual.

Video: Music can spark creativity in math and science.

Video: Aerial surveillance cameras in some stores track our shopping behavior and help retailers determine what to sell and how to position it.

Video: Digitized images of very thin slices of the human brain are used to determine whether behavior patterns are reflected in the structure of the brain.

Minnesota educator develops multimedia tools to share and preserve Ojibwe language and culture.

From the birth of Jesus in a manger to the Star of Bethlehem, the details of the Nativity story show up in Christmas pageants and storefront windows everywhere.

The 40 Bags in 40 Days challenge encourages you to tackle one area of clutter in your home each day and get rid of it responsibly.

Five years in the making, the film takes audiences on an interfaith journey through one of the world's 'most storied' cities.

2,500-year-old stone slab could offer clues to deciphering the lost language and religion of the Etruscans.

Grimbergen Abbey will use centuries-old books as inspiration to start brewing beer again after more than 200 years.

Why Volkswagen should bring back the Microbus.

From soothing sore throats and upset stomachs to fighting hiccups and diabetes, the health benefits of apple cider vinegar go beyond fold remedies.

How to pollen-proof your life with these 20 tips for seasonal allergy sufferers.

As the first plug-in electric vehicles come to the mass market, companies that design and sell car chargers are battling for market share.

Don't let bucolic images of small, locally owned farms cloud your judgment. Our blogger says do your homework and buy local when you can.

A 30-week Urban Farm School program begins on April 1 at the Ashevillage Institute and Sanctuary in North Carolina.

Agriculture Department's deputy secretary has been a champion of local and organic foods, farm-to-school programs and more.

After graduating from college, Daniel Mays followed his heart back to the land and has been working to build his own small organic farm up here in Maine.

This book takes you on a journey to an organic Japanese farm through personal stories and recipes.

Decades after the world's two biggest previous nuclear disasters, NBC's Jeff Rossen and Michelle Kosinski look back at the impact of the meltdowns.

These maps, graphs and charts will answer your questions about radiation exposure and nuclear energy.

A historic moment for the energy industry — leading technology company Siemens abandons its nuclear division in favor of growing wind market.

The three-term New York mayor was famous for his outspoken persona and economic rekindling, but he also had a little-known green streak.

For people living in areas neighboring the Fukushima nuclear power plants, the worst of the radiation exposure may have passed.

Lockheed Martin recently claimed to have designed a fusion reactor that can fit on the back of a truck. If viable, it really could change the world.

Watch how carefully a large dam is deconstructed in this time-lapse video showing the removal of Oregon's Gold Ray dam.

In "Ajijaak on Turtle Island," a young crane's migration journey brings Native American stories to life.

Researcher Lindsey Swierk discovered that when water anoles flee underwater to escape predators, they stay underwater for a long time.

In an interview with MNN, Tesla CEO Elon Musk is candid about his company's finances, the competition, the Model S and its prospects for the future.

Tesla CEO Elon Musk is nothing if not outspoken. Here, in the second of three interview segments, he talks about prospects for the company's affordable Model S

British Parliament is striving to reduce its carbon footprint through various efficiency measures, including potentially outfitting Big Ben with PV panels.