Today is Earth Day, a day set aside for awarenesss and appreciation of the Earth's environment, and our roles within it - this year marking the 40th anniversary of Earth Day. As a way to help appreciate and observe our environment, I've collected 40 images below, each a glimpse into some aspect of the world around us, how it affects and sustains us, and how we affect it. Happy Earth Day everyone
This view of Earth, featuring North, Central and South America was taken by the NASA probe called Messenger, while conducting a fly-by of our planet in order to pick up a gravity-assist boost on its way toward Mercury
A farmer tends to his blooming rape seed field in the hills above Burford in the Cotswolds on April 21, 2009 in Burford, United Kingdom.
This undated handout photo provided by the journal Science shows Iron oxides staining the snout of the Taylor Glacier, in the McMurdo Dry Valleys, Antarctica, forming a feature commonly referred to as Blood Falls. The iron originates from ancient subglacial brine that episodically discharges to the surface. Outflow collected at Blood Falls provides access to a unique subglacial ecosystem that harbors a microbial consortium which actively cycles iron, sulfur and carbon for growth.
Sprinklers water a field at sunset on April 16, 2009 north of Buttonwillow, California. Central Valley farmers and farm workers are suffering through the third year of the worsening California drought with extreme water shortages and job losses.
Local miner Cesar Abac uses a wooden bowl and mercury to pan for gold near at the village of Las Cristinas, southern Bolivar State, Venezuela on January 30, 2009. Four centuries after the lure of Venezuelan gold brought ruin to English explorer Sir Walter Raleigh, the riches at one giant mine some say is cursed still haunt treasure hunters from across the globe. But the Las Cristinas saga, involving a ghost town, environmental devastation and fist-sized nuggets, underlines the risks of business in Venezuela, where the draw of natural wealth has been dulled by rule changes and economic turmoil.
This photo from 1997, released by Woods Hole Oceanographic Institution shows the robotic arm of a three-person submersible aquatic vehicle reaching toward a hydrothermal vent in the east Pacific Ocean far off the coast of Chile. New technology and worldwide demand for metals have combined to make deep ocean mining of the mineral-laden liquid spewed from these vents a possibility. 
A humpback whale raises its tail as it prepares for a deep dive in the Santa Barbara Channel off the coast of Oxnard, Calif. on Sunday afternoon, April 19, 2009. The offshore oil platform "Gail" is seen in the background
Ferid Sinan, a 40-year-old Bosnian man, carries a bag of coal out of an illegal coal mine, where he lives and works, near the central Bosnian town of Kakanj,30 kms north of Sarajevo, on Friday, March 13, 2009 . Sinan lives and works in the improvised mine which he dug himself, collecting low quality coal with his hands and primitive tools to make a living earning less than 5 euros per bag.
Sunrise in windy Langdon, North Dakota, where the Langdon Wind Energy Center can be found. The center produces 159 megawatts with over 100 turbines.
Workers stand by to mount a propeller as a crane lifts it to the top of a power-generating windmill turbine in the northern German city of Hamburg on March 20, 2009. This single turbine can produce 6 megawatts of energy and is the first of two new power-generating windmills, built in the harbour area of Hamburg
A silhouette of a single snow goose is seen as it flies beneath the moon at the Middle Creek Wildlife Management Area in Kleinefeltersville, Pa. Snow geese are on their spring migration north to their nesting habitats in arctic tundra regions
Analyzing a variety of samples from the atmosphere above the Amazon, Ilan Koren and colleagues at the Weizmann Institute in Israel, show in the journal Science that smoke and other so-called "aerosol" particles can encourage or discourage cloud formation, depending on the conditions, and a their new scientific model shows how these two processes produce a joint effect on climate
An Afghan man mines rock to make sand for use in construction in Kabul, Afghanistan on April 13, 2009
Snow-covered pine trees sit in flood water March 31, 2009 near Moorhead, Minnesota. A snowstorm had slowed recovery efforts as residents of Moorhead and neighboring Fargo, North Dakota returned to their homes as the Red River slowly receded
A North Dakota Air National Guard helicopter carries six 1,000-pound sandbags to the edge of the Clausen Springs dam Wednesday, April 15, 2009, as an attempt was being made to control the erosion of the emergency spillway
This undated photo provided by BrightSource Energy shows their Luz Power Tower in Israel's Negev Desert (mirrors concentrate sunlight on the tower at center). BrightSource has proposed building three solar-energy generation complexes in the eastern Mojave Desert several miles from an old mining and railroad townsite called Ivanpah, Calif. A westward dash to power electricity-hungry cities by cashing in on the Mojave's most abundant resource - sunshine - is clashing with efforts to protect species like the tiny pupfish and desert tortoise.
Solar panels stand in a field of flowers at Acciona SA's solar power station in Amareleja, Portugal, on Tuesday, April 14, 2009. The 46-megawatt facility, has a production capacity of 93 million kilowatt-hours a year, and is the world's biggest photovoltaic electricity plant
An enormous iceberg, right, breaks off the Knox Coast in the Australian Antarctic Territory on Jan. 11, 2008
An aerial photograph shows a wall being built by Rio de Janeiro city hall to limit the expansion of the Santa Marta slum and stop encroaching on the neighboring forest in Rio de Janeiro, Brazil on March 28, 2009.
Stars in the night sky rotate above the distinctive chimney stack on the top of Cape Cornwall near St. Just on April 12, 2009 in Cornwall, England. The landmark, orginally built for the Cape Cornwall Mine in 1850 and was recently damaged when it was struck by lightning, was bought, along with the rest of Cape Cornwall, for the nation by Heinz in 1987 and given to the National Trust to mark Heinz's centenary
Minnows are deposited through a tube from a tanker truck into Lake Delton as area officials take the first steps in restocking the lake, Monday, April 20, 2009, in Lake Delton, Wisconsin. The minnows will serve as food for larger game fish to be stocked in June. A section of the manmade lake's shore washed away during thunderstorms last June, and the entire lake drained through the opening
A Kenyan fisherman holds a fish that had escaped from his fishing net, Saturday, Feb. 28, 2009 in the waters of Diani on the Kenyan south coast. Plastic fishing nets, some bought for poor fishermen with American aid money, are tangling up whales and turtles on Diani, one of Africa's most popular beaches
A plant stands in front of piles of waste paper being shipped to mainland China for recycling, at a collection site in Hong Kong on Earth Day April 22, 2009.
A bird flies past dumped plastic bottles and other garbage on the bank of the river Sava in Belgrade, Serbia on April 22, 2009
The Llaima volcano spews smoke and lava some 850 km (528 miles) south of Santiago, Chile in this January 2, 2008
Residents walk in debris after a dam burst in Jakarta, Indonesia, Sunday, March 29, 2009. Attention shifted to caring for homeless and hungry survivors after the dam burst outside the Indonesian capital, sending a wall of water crashing into homes and killing at least 91 people, and leaving more than 100 others missing.
A red-tailed hawk uses its talons to to grab a meal of Brazilian free-tailed bat as a cloud of the bats emerges from Frio Cave near Uvalde, Texas, during an evening hunt for insects.
Work is underway at a new oil well seen Tuesday, April 21, 2009, in the Sakhir, Bahrain, desert oil fields of the Persian Gulf. 
Lebanese workers use water pressure to clean-up the oil spill which polluted Rabbit Island, offshore the Nothern Lebanese city of Tripoli, on March 31, 2009. The oil spill was caused by the explosion of fuel reservoirs stationed in the southern coastal town of Jiyyeh during the
Tropical Cyclone Billy, off the coast of Western Australia on December 25, 2008
Russian Emergency Ministry staff watch a blast ripping through the ice covering the Kan river in the town of Kansk some 220 km (136.7 miles) from the Siberian city of Krasnoyarsk April 4, 2009. Explosive experts used dynamite to break the ice cover to ease pressure that could cause floods as melting snow increases the river's water volume
A Polish seasonal worker takes part in the asparagus harvest in a field near the eastern German town of Klaistow on April 13, 2009. Hundreds of seasonal workers travel to Germany every year from eastern European countries to help out with the asparagus harvest
Green glass bottles are piled up high over an area estimated to be the size of a soccer field, near a recycling plant in the southern Israeli town of Yeruham, Israel, Wednesday, March 25, 2009. The green bottles are from all types of bottles and are separated for recycle purposes near to the processing plant
A male Asian Longhorned beetle, held up to the camera. A recent infestation of the Asian Longhorned beetle in central Massachusetts has mobilized forestry officials and lawmakers to rein it in. The beetles are wood-boring insects that attack a variety of native hardwood species, their larvae tunnel through the heartwood of a host tree until fully grown, then they burrow out of the trunk as an adult, weakening the wood
Elang, an Indonesian student, swims in foamy, polluted waters after school, at the Pluit Dam in Jakarta, Indonesia on April 20, 2009
A wolf walks on an empty road in a forest inside the 30 km (18 mile) exclusion zone around the Chernobyl nuclear reactor near the village of Babchin, Belarus, some 370 km (217 miles) southeast of Minsk, February 2, 2009. Still inhospitable to humans, the Chernobyl "exclusion zone" is now a nature reserve and teems with wolves, moose, bison, wild boars and bears.
