New research suggests that Earth's oxygenation didn't require difficult and complex evolutionary leaps forward.
Vladi333 / shutterstock
Oxygen flooded the atmosphere for the first time and then ... nothing. Or so we thought.
Earth is really ancient, and humans have only been around for a tiny part of that time.
All the buildings and the cars and the restaurants, and the phones and even everything that's inside of you... it all started with an exploding star, billions of years ago.
Droplets rising from the Champagne vent on the ocean floor in the Mariana Islands. Fluids venting from the site contain dissolved carbon dioxide.
NOAA Ocean Explorer
Thousands of years ago, carbon gases trapped on the seafloor escaped, causing drastic warming that helped end the last ice age. A scientist says climate change could cause this process to repeat.
The research vessel must dodge dangerous icebergs as it drills for sediment core samples.
A paleooceanographer describes her ninth sea expedition, this time retrieving cylindrical 'cores' of the sediment and rock that's as much as two miles down at the ocean floor.
An eruption of Anak Krakatau caused an underwater landslide and tsunami that struck Java and Sumatra.
Nurul Hidayat/Bisnis Indonesia via AP
Research into volcanic activity in the waters off Indonesia shows how active this region is and how destructive landslide-caused tsunamis can be.
It’s core to life on Earth.
The Earth's core is cooling down, and one day it will be completely solid – when that happens, Earth might look a lot like Mars.
Arts Illustrated Studios/Shutterstock
Gravity, not magma, is forcing Etna to move, increasing the chances of collapse.
The scientific drilling ship JOIDES Resolution arrives in Honolulu after successful sea trials and testing of scientific and drilling equipment.
The ocean floor holds unique information about Earth's history. Scientific ocean drilling, which started 50 years ago, has yielded insights into climate change, geohazards and the key conditions for life.
Cumberland Island National Seashore off the coast of Georgia.
How do the narrow ribbons of sand that line the Atlantic and Gulf coasts withstand the force of hurricanes? The answer lies in their shape-shifting abilities.
Vadim Sadovski / shutterstock
We're still not sure whether the "hothouse" is speculation – or destiny.
What’s going on 150 kilometers below the Earth’s surface?
Good Free Photos
A new array of seismometers provides a glimpse of what's happening deep beneath this geologic fault. New data help explain why the north and south of the region are more seismically active than the middle.
Long’s Peak framed by rock outcrop, Rocky Mountain National Park, Colorado.
Scientists have long thought most nitrogen in Earth's ecosystems comes from the air, but new research shows it also is released as rocks weather. This could boost plant growth and help sequester carbon – but not fast enough to avert climate change, as some pundits have claimed.
Seismic shockwaves after a meteorite’s collision could affect systems all over the planet.
Research suggests a new threat to life on Earth from the meteorite's crash: Via seismic waves, the impact triggered massive undersea eruptions, as big as any ever seen in our planet's history.
Fires break out across San Francisco after the April 18, 1906 earthquake.
According to current forecasts, California has a 93 percent chance of an earthquake with magnitude 7 or greater occurring by 2045. Early warning systems, now in development, could limit casualties and damage.
A new study has found a way to predict eruptions at Mount Etna within two weeks.
Searching for victims after a rain-triggered mudslide that blanketed a village and killed at least 178 people in north China’s Shanxi province, Sept. 13, 2008.
AP Photo/Andy Wong
While the Montecito, California mudslides took 20 lives, landslides kill far more people in developing countries. Tighter construction standards and early warning systems could help reduce their toll.
Where there’s smoke, there will be lava?
U.S. Geological Survey via AP
How do scientists predict volcanic eruptions? To do so with accuracy, they need to know the individual volcano and its history very well.
Mercury found in prehistoric rock bolsters the idea that volcanoes caused a mass extinction 200m years ago.
Average carbon dioxide concentrations, Oct. 1 -
Nov. 11, 2014, measured by the Orbiting Carbon Observatory-2 satellite.
Why use satellites to study Earth's climate? Researchers leading a new mission explain how images from space will help them analyze which parts of the Americas soak up the most carbon.