Through his spyglass, in 1609 Galileo saw that there were spots on the Sun, imperfections on the Moon, and that the Milky Way was composed of millions of faint stars. His most stunning (and controversial!) discovery was of satellites orbiting Jupiter, dashing the concept that the Earth was the center of the Universe.

A century ago, Albert Einstein predicted gravitational waves -- ripples in the fabric of space-time that result from the universe's most violent phenomena. NSF-funded researchers, using one of the most precise instruments ever made -- the Laser Interferometer Gravitational-wave Observatory (LIGO) -- have detected gravitational waves that emanate from 1.3 billion years ago. Find out more...

Saturn is huge. It is the second largest planet in our Solar System. Only Jupiter is bigger. If you could line them up, more than nine Earths would fit across Saturn. Although other planets have rings too, Saturn's rings are the only ones that are visible from Earth even with a small telescope.

The Wright 1905 Flyer, the first practical airplane, flew for 33 minutes and 17 seconds, covering a distance of 20 miles, on October 4, 1905.

On October 14, 1947, in the rocket powered Bell X-1, Capt. Charles E. Yeager flew faster than sound for the first time.

A team of Arizona scientists has discovered microbial life about a foot below the parched surface soil of one of the driest places on earth -- Chile's Atacama Desert. Their finding may influence how scientists look for life in a similarly extreme location -- Mars.

The Earth currently has more than 400 oceanic dead zones, with the count doubling every decade. A single dead zone may cover tens of thousands of square miles.

A team searching deep in a South African gold mine has found bacteria that subsist in rock at huge pressure for thousands of years by ’eating‘ by-products of radioactivity, completely isolated from any organic matter or effects of photosynthesis.

Since the late 1990s, Lake Erie has been plagued with blooms of toxic algae that turn its waters a bright blue-green. These harmful algae blooms are made up of cyanobacteria that produce the liver toxin microcystin. The blooms have led to public warnings to avoid water contact.

One of the fastest-growing organisms on Earth is giant kelp. This large seaweed can grow 2 feet a day and reach almost 150 feet in length -- in one growing season. Growth spurts of this large seaweed are fueled by a diet of dissolved nitrogen.

Extremophiles are organisms capable of living in conditions that would kill other life-forms, including intense cold, heat, pressure, dehydration, acidity/alkalinity and other chemical and physical extremes. A few animals, such as frogs that freeze solid in winter, can qualify. But in large part, the world’s endurance champs are microbes: bacteria and archaea.

Deforestation accounts for 11 percent of human-caused greenhouse gas emissions.

The percentage of Africa that is wilderness: 28%

The percentage of North America that is wilderness: 38%