Our fragile Earth

Stretching across part of southwestern Bangladesh and southeastern India, the Sundarbans is the largest remaining tract of mangrove forest in the world. The Sundarbans is a tapestry of waterways, mudflats, and forested islands at the edge of the Bay of Bengal. Home to the endangered Bengal tiger, sharks, crocodiles, and freshwater dolphins, as well as nearly two hundred bird species, this low-lying plain is part of the Mouths of the Ganges. The area has been protected for decades by the two countries as a National Park, despite the large human populations concentrated to the north. This satellite image shows the forest in the protected area. The Sundarbans appears deep green, surrounded to the north by a landscape of agricultural lands, which appear lighter green, towns, which appear tan, and streams, which are blue. Ponds for shrimp aquaculture, especially in Bangladesh, sit right at the edge of the protected area, a potential problem for the water quality and biodiversity of the area. The forest may

This NASA handout image captured by Canadian astronaut Chris Hadfield on board the International Space Staion(ISS) on April 6, 2013, shows contrails from jet traffic over San Francisco. AFP PHOTO/HANDOUT/ NASA / Chris Hadfield = RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT \" AFP PHOTO / NASA / Chris Hadfield \" - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS =Chris Hadfield/AFP/Getty Images

This NASA handout image captured by Canadian astronaut Chris Hadfield on board the International Space Staion(ISS) on March 20, 2013, shows the Nile River, the Nile River delta, the Sinai Peninsula and beyond. AFP PHOTO/HANDOUT/ NASA / Chris Hadfield = RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT \" AFP PHOTO / NASA / Chris Hadfield \" - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS =Chris Hadfield/AFP/Getty Images

From the International Space Station: Morning clouds cast self-important shadows off the coast of China on Feb. 9. 2013. pic.twitter.com/kxDJPNGw

View from the International Space Station on Feb. 20, 2013. Arid fingers of sand-blasted rock look like they're barely holding on against the hot Saharan wind. pic.twitter.com/CKRpDKy8

Patchwork of farms covered in snow in Central Asia as seen from space. MISP

NASA Earth Observatory The night lights of the Americas shine in this visualization of our planet at night, which is based on data acquired by the Suomi NPP satellite in April and October. The image, released by NASA Earth Observatory today, has been nicknamed the \"Black Marble.\"