Meet "Big Red," a new species of jellyfish that is bulbous, dusky red, and huge, nearly one meter (about three feet) in diameter, with several fleshy arms instead of tentacles, like a balloon with greedy fingers.

Learn more about these forests, once generally dismissed as swampy wastelands but now valued as remarkably diverse and important ecosystems.

Investigate this remarkably tough plant that can live in water up to 100 times saltier than most other plants can tolerate, not to mention thrive despite twice-daily flooding by ocean tides.

In a handful of cases, humans have contracted H5N1 from birds and then passed the virus to other humans. Even so, doctors and scientists are taking great pains to prepare for the possibility of such a pandemic.

Straddling land and sea and teeming with life, mangrove forests are key to healthy coastal ecosystems. They're also among the most threatened habitats in the world. Learn more.

Thanks to an innovative grassroots organization called Yad Fon, southern Thailand's Trang Province is home to an inspiring example of ecosystem restoration. Learn more.

While technological advances are making it easier for the 21 million diabetics in the United States to manage healthy lives, diabetes is still a disease that requires vigilance. See how scientists are using stem cells to find a cure.

On cloudless, moonless nights, the stars are so bright over the remote village of Sutherland, South Africa, that a person can walk by starlight alone. Learn more about the village’s Southern African Large Telescope (SALT).

A series of satellite photographs taken by NASA's Mars Global Surveyor, which has been mapping Mars since 1999, raise the exciting possibility that liquid water may have existed there very recently.

Earth's water is in constant motion. It cycles through the planet's atmosphere, surface, and depths. This water cycle is fundamental to Earth’s climate — and is being dramatically affected by global warming.