NASA has opened voting for itsTournamentEarth 2014 photo competition
, which takes Earth images captured by satellite and makes them go head to head. Users (that's you!) vote on the best shots, which then go on to the final round. You can create your interactive brackethere
. Note: Voting ends Friday, March 14. Our favorite to take the whole thing: An eruption at Kliuchevskoi, a stratovolcano on the Kamchatka Peninsula of Russia (above) was photographed by the Expedition 38 crew aboard the International Space Station.PHOTOS: 2013 Top 20 Earth Images Contest
NASA/ISS Crew Earth Observations experiment and Image Science & Analysis Laboratory, Johnson Space Center
Tristan da Cunha, an island in the southern Atlantic Ocean, is more than 2,300 miles (3,700 kilometers) from the coastline of Antarctica. A volcano sits at the island's center. "The last known eruption of Tristan da Cunha took place in 1961–1962," writes William L. Stefanov for NASA, "and forced the evacuation of the only settlement on the island, Edinburgh of the Seven Seas, on the northern coastline (obscured by clouds in this image). The town is considered to be the most remote permanent settlement on Earth, with its nearest neighbor located 2,173 kilometers (1,347 miles) to the northeast on the island of St. Helena."PHOTOS: Changing Face of Earth in 2013
NASA image courtesy Jeff Schmaltz, LANCE MODIS Rapid Response Team at NASA GSFC.
Alaska is the cloudiest region of the United States, reports the space agency, but last summer, NASA's Terra satellite caught a rare, nearly cloud-free view.PHOTOS: The Stinkiest Places on Earth
NASA Earth Observatory images by Holli Riebeek, using Landsat 8 data from the USGS Earth Explorer
In early November of 2013, a large iceberg calved off the front of Antarctica’s Pine Island Glacier, which was captured by the Operational Land Imager on the Landsat 8 satellite.PHOTOS: A View of the Unnatural World From Space
NASA image courtesy Jeff Schmaltz, LANCE MODIS Rapid Response
In late January 2013, snow blanketed Great Britain from London in the south to Edinburgh, Scotland, in the north. The image was captured by the The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite. But you knew that.PHOTOS: Green Earth Beauty
NASA image courtesy Jeff Schmaltz LANCE/EOSDIS MODIS Rapid Response Team, GSFC
The Canary Islands appear to have tails made by smooth and choppy water, and the reflection of sunlight. The image was captured by the same satellite that photographed Great Britain under snow. All of these images are in the current Round of 16. Got a favorite?You can't win if you don't play
.PHOTOS: Pyramids Hidden In Satellite Images?
The movement of Earth's major continental tectonic plates is speeding up, suggests a new study.
The study, presented at the Goldschmidt Geochemistry Conference in Sacramento California, challenges the idea that the rate of plate movement remains stable.
"This is quite mind boggling," says Professor Kent Condie of the New Mexico Institute of Mining and Technology, who led the study.
"It's different from what most people thought because Earth is cooling and everybody assumed plate movements would slow down."
Continental drift is caused by heat deep in the planet, driving the convection of material in the Earth's mantle.
The eight major and numerous minor tectonic plates on the planet's surface are moved by these convection currents.
Condie's research, which has been submitted for publication in the Precambrian Research Journal, examines how supercontinents assemble and break up.
To identify how continents have moved, Condie and colleagues looked at the geomagnetic record in the Earth's crust to see how much it has changed over time.
The researchers found the frequency with which continents have been colliding has been increasing over at least the last two billion years maybe longer.
They also found the a rate at which new supercontinents form has been increasing, and the length of time ocean basins last has been decreasing.
"All of these lines of evidence indicate plate tectonics is speeding up, not slowing down," says Condie.
Why continental drift is accelerating, however, is a mystery, says Condie.
A separate paper presented at the Goldschmidt conference led by Professor Peter Cawood of the University of St. Andrews in the United Kingdom, also suggests the rate of continental drift has changed over time.
Cawood and colleagues examined earlier studies on continental movement, finding the planet was stable between 1.7 to 0.75 billion years ago — a time known as Earth's 'middle age' — which coincides with the formation of the Rodinia supercontinent.
During this time, they found there was little new crust building activity, no major changes in atmospheric composition and few major developments in the fossil record.
In contrast, major ice ages and changes in oxygen levels occurred on either side of this period.
Cawood suggests the stability seen during the Rodinia supercontinent epoch may have been due to the gradual cooling of Earth's crust.
"Before 1.7 billion years ago, the Earth's crust would have been substantially hotter, meaning that continental plate movement may have been governed by different rules to those that operate today," says Cawood.
"[750 million years ago], the crust reached a point where it had cooled sufficiently to allow modern day plate tectonics to start working, in particular allowing subduction zones to form where one plate of the crust moves under another."
This increased activity could have kick-started a series of events, including the break-up of Rodinia and changes to levels of key elements in the atmosphere and seas.
"This in turn may have induced evolutionary changes in the life forms present at the time," says Cawood.
Article originally appeared on ABC Science Online.