1. Lava Around Lake Afrera

    In the Danakil Depression in northern Ethiopia, Earth is tearing itself apart. Three tectonic plates—the Arabian, Nubian, and Somalian—are sliding away from each other at a rate of a few centimeters per year. As they diverge, they leave a widening rift valley that will eventually become ocean floor. For now, Eastern Africa is one of the few places where it’s possible to see a spreading ridge—a feature normally found in the ocean—on dry land.

    Danakil is also a good place to see lava fields extending across barren desert. The Operational Land Imager (OLI) on Landsat 8 captured this scene of the landscape around Lake Afrera (or Giulietti) on January 18, 2014. The top image is a detailed view of the area within the white box in the lower image. Sedimentary deposits of sand and evaporites appear tan; lava fields and flows are black or grey. The chemical composition of the lava, as well as how long it has been exposed to weathering, can affect its color.

    Erte Ale, the most active volcano in Ethiopia, is the source of the lava field northwest of the lake. Borawli, an inactive stratovolcano, is the source of much of the lava to the east of the lake. The darker flow south of Lake Afrera came from Alayta, a large shield volcano that covers an area of 2,700 square kilometers (1,000 square miles). Immediately to the right of the Alayta is a lava field composed of a lighter-colored rhyolitic lava fromAfdera. Young basaltic lava like that from Alayta tends to be black or dark grey. Over time, basalt usually takes on a lighter, redder tone as the iron within it oxidizes.

    Afrera, the salty lake in the center of the image, is fed by natural hot springs in the northeastern and southeastern part of the lake. The white rectangles around the shore of the lake are evaporation ponds, which are used to produce salt. The small island within the lake, Franchetti Island, sits 100 meters (328 feet) below sea level, making it one of the lowest-lying islands in the world.

    NASA Earth Observatory images by Robert Simmon, using Landsat 8 data from the USGS Earth Explorer. Caption by Adam Voiland. Congratulations to Samer Jamal and Angus Howden for being the first readers to solve the puzzler.

    Instrument(s): Landsat 8 - OLI
  2. Diamonds in the Sub-Arctic Rough

    Home to many natural wonders and resources, Canada’s Northwest Territories have undergone increased development in recent years. One area of highly visible development has been the Lac de Gras kimberlite field, about 220 kilometers (150 miles) south of the Arctic Circle. Kimberlites mean one thing: diamonds.

    Named for deposits first found in Kimberly, South Africa, kimberlites are forged deep within Earth’s mantle. Under intense pressure and heat, carbon is squeezed into diamonds and then erupted to the surface in kimberlite pipes. The Lac de Gras kimberlite field in Canada is one of those places where diamonds have been pushed toward the surface, so the region has been developed extensively over the past decade to harvest the valuable geological deposits.

    One such development is the Diavik Diamond Mine, which opened in 2003. The operation employs 700 people, produces about 1,500 kilograms of diamonds each year, and grosses $100 million (Canadian) in annual sales. The nearby Ekati Diamond Mine opened in 1998 and has a similar annual production to Diavik. Download the large images to see Ekati.

    The images at the top of this page were captured by the Landsat 5 satellite on July 3, 1998 (top), and by Landsat 8 on July 5, 2013. They show an area centered around 64.50° North and 110.27° West. (Turn on the image-comparison tool to see the fine details of development.) The mine was started as an open pit, so great changes occurred in the past 15 years. However, future changes are not likely to be as visible at the surface because the operators of Diavik have transitioned most production underground.

    Diavik Diamond Mine is essentially an industrial complex and town in one, all set in a remote, sub-Arctic landscape. In the 2013 image, you can see two main open pits, waste rock piles, and an airstrip capable of landing aircraft as large as 737s and C-130s. The complex also houses processing plants, fuel tanks, water and sewage processing facilities, administrative buildings, and accommodations for workers and other residents.

    1. Related Reading

    2. CBC News (2013, July 20) N.W.T. board approves territory’s 4th diamond mine Accessed July 25, 2014.
    3. HowStuffWorks Carbon and Kimberlite. Accessed July 25, 2014.
    4. Missens, R., et al. (2007). Aboriginal partnerships in Canada: focus on the Diavik Diamond Mine. Journal of Enterprising Communities: People and Places in the Global Economy, (1) 54–76.
    5. National Public Radio (2008, December 11) Mining for Diamonds in the Canadian Rough. Accessed July 25, 2014.
    6. Natural Resources Canada (2002, June 1) Geology, Lac de Gras kimberlite field. Accessed July 25, 2014.
    7. Wikipedia (2014) Diavik Diamond Mine. Accessed July 25, 2014.
    8. Wikipedia (2014) Lac de Gras kimberlite field. Accessed July 25, 2014.

    Earth Observatory images by Robert Simmon, using data provided by the U.S. Geological Survey. Caption by Allen Pope (@PopePolar), with Mike Carlowicz.

    Instrument(s): Landsat 5 - TMLandsat 8 - OLI
  3. Okavango Delta

    The great Okavango Delta in the Kalahari Desert is illuminated in the Sun’s reflection point in this panorama taken from the International Space Station (ISS). Using this sunglint technique, astronauts can capture the fine detail of water bodies.

    In this image, the bright line of the Okavango River shows the annual summer flood advancing from the well-watered Angolan Highlands (upper image margin). The flood water slowly seeps across the 150 kilometer-long (100 mile) delta—supplying forests and wetlands—and finally reaches the fault-bounded lower margin of the delta in the middle of winter. The wetlands support a highly diverse number of plant and animals species in the middle of the otherwise semiarid Kalahari Desert. For this reason, the Okavango Delta is now one of the most famous tourist sites in Africa.

    Most of the water from the Okavango River is consumed by forests or evaporates in the dry air. Only 2 percent of the river’s water actually exits the delta. This photograph shows the small quantity of water exiting through the Boteti River. Okavango water only reaches the dry lake floors (visible on the lower edge of the large image) in the wettest years.

    Part of one of the ISS solar arrays is visible on the right.

    Astronaut photograph ISS040-E-8209 was acquired on June 6, 2014, with a Nikon D3S digital camera using a 42 millimeter lens, and is provided by the ISS Crew Earth Observations Facility and the Earth Science and Remote Sensing Unit, Johnson Space Center. The image was taken by the Expedition 40 crew. It has been cropped and enhanced to improve contrast, and lens artifacts have been removed. The International Space Station Program supports the laboratory as part of the ISS National Lab to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth. Caption by M. Justin Wilkinson, Jacobs at NASA-JSC.

    Instrument(s): ISS - Digital Camera
  4. canadian-space-agency:

    Houston under a lightning storm as seen from space on June 27th 2014.

    Credit: NASA Astronaut Reid Wiseman

    (Source: vine.co)

  5. Houston Ship Channel, Texas

    This astronaut photograph depicts the San Jacinto River portion of the Houston Ship Channel, one of the United States’ busiest sea ports. The channel is a conduit between the continental interior and the Gulf of Mexico for both petrochemical products and Midwestern grain. The original watercourse for the channel, Buffalo Bayou, has its headwaters thirty miles to the west of the city of Houston. It has been used to move goods to the sea since at least 1836. Wakes of ships traveling along the channel are visible to the south of the Goat Islands (bright, oblong islands at top center of image). The close proximity to Texas oilfields led to the establishment of numerous petrochemical refineries along the waterway, such as the ExxonMobil Baytown installation on the eastern bank of the San Jacinto River.

    While much of the Ship Channel is associated with heavy industry, two icons of Texas history are also located along its length. The inset (area denoted by white rectangle) highlights the battleship USS Texas and the San Jacinto Monument.The Texas saw service during both World Wars, and is the last remaining example of a dreadnought-class battleship in existence. The nearby San Jacinto Monument commemorates the 1836 battle in which Texas won its independence from Mexico. The monument itself is a 570-foot-high (173-meter) shaft topped by a 34-foot-high (10-meter) star, making it 15 feet (5 meters) higher than the Washington Monument in Washington, D.C.

    The Houston Ship Channel has been periodically widened and deepened to accommodate ever-larger ships, and is currently 530 feet wide by 45 feet deep by 50 miles long (161 meters by 14 meters by 80 kilometers). The islands in the ship channel are part of the ongoing widening and deepening project. The islands are formed from soil pulled up by dredging, and the salt marshes and bird islands are part of the Houston Port Authority’s beneficial use and environmental mitigation responsibilities.

    Astronaut photograph ISS012-E-9567 were acquired November 28, 2005, with a Kodak 760C digital camera using an 800 mm lens, and is provided by the ISS Crew Earth Observations experiment and the Image Science & Analysis Group, Johnson Space Center. The International Space Station Program supports the laboratory to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth.

    Instrument(s): ISS - Digital Camera
  6. Yellow River Delta, 1989 and 2009

    China’s Huang He (Yellow River) is the most sediment-filled river on Earth. In the lower reaches, where the current slows, the natural accumulation of sediment in the riverbed has caused the river to change course often in the past. Since the mid-nineteenth century, however, the lower reaches of the river and the delta have been extensively engineered to control flooding and to protect coastal development.

    This pair of natural-color images from NASA’s Landsat satellites shows the Yellow River Delta at the river mouth in 1989 and 2009—two images from a series showing the delta at five year-intervals over the past two decades. In 1989, the river’s main channel emptied into the Bohai Sea in a southeast-bending arc. In 1996, Chinese engineers blocked the main channel and forced the river to veer northeast, delivering sediment to a new location. By 2009, a new peninsula had formed, the old one had retreated, and shoreline northwest of the new river mouth had filled in considerably.

    The filling-in of that section of shoreline may be the outcome that the engineers were anxious to achieve: the land northwest of the newly fortified shoreline is home to an extensive field of oil and gas wells. Their protection is a primary concern.

    Although levees, jetties, and seawalls allow officials to slow erosion and direct the flow of the river, other challenges to protecting the delta’s natural wetlands and its agricultural and industrial development remain. Water and sediment flows to the delta have declined dramatically since the 1970s, due to both reduced rainfall and explosive urban and agricultural demand for water upstream. In the 1990s, the river frequently ran dry well before reaching the delta.

    1. References

    2. Baosheng, W., Zhaoyin, W., and Changzhi, Li. (2004). Yellow River Basin management and current issues. Journal of Geographical Sciences, 14, supplement, 29-37.
    3. Chu, Z., Sun, X., Zhai, S., and Xu, K. (2006). Changing pattern of accretion/erosion of the modern Yellow River (Huanghe) subaerial delta, China: Based on remote sensing images. Marine Geology,227, 13-30.
    4. Li, S., Wang, G., Deng, W., Hu, Y., and Hu, W. (2009). Influence of hydrology process on wetland landscape pattern: A case study in the Yellow River Delta. Ecological Engineering, 35, 1719-1726.
    5. Liu, J.P., Milliman, J., Gao, S., and Cheng, P. (2004). Holocene development of the Yellow River’s subaqueous delta, North Yellow Sea. Marine Geology, 209, 45-67.
    6. Xue, C. (1993). Historical changes in the Yellow River delta, China. Marine Geology, 113, 321-329.

    NASA images by Robert Simmon. Caption by Rebecca Lindsey.

    Instrument(s): Landsat 5 - TM
  7. A Disappearing Island Restored

    Not so long ago, many islands rose above the brackish waters of the Chesapeake Bay. These small islands offered a predator-free haven for nesting water birds and turtles, while the larger islands supported fishing communities along with wildlife. But now, the muddy, marshy islands are eroding under the combined forces of geology and climate change. The very crust under the Chesapeake Bay is sinking, while sea levels are rising. Made of clay and silt, the islands erode quickly, and many have disappeared altogether.

    Poplar Island ranks among those that would have been gone a decade ago if not for a massive restoration project. In the 1800s, the island had an area just over 1,000 acres and held a small town of about 100 people. By the 1990s, the island was nearly gone, containing a mere 10 acres of land. In the left image, taken by the Landsat 5 satellite on June 28, 1997, Poplar Island had been reduced to a tiny green dot surrounded by clouds of silt-laden water.

    In 1998, the U.S. Army Corp of Engineers began to restore Poplar Island. The project serves two purposes: it restores lost habitat to birds and turtles, and it provides a use for material dredged from Baltimore Harbor and Chesapeake Bay shipping lanes. The method of restoration is visible in the center image, taken on June 21, 2006. Engineers built dikes around sections of the island and have been gradually filling in the center with dredged silt. By 2006, the island had regained the shape it held in the 1800s.

    As each cell is filled with new soil, the Army Corp of Engineers plants vegetation. The right image, taken on July 5, 2011, shows that much of the island has been re-vegetated. Poplar Island now has an area of 1,140 acres and may continue to expand by another 500 acres before the restoration is completed in 2027. Upon completion, Poplar Island will be half wetlands and half uplands covered by forest. The restoration project is expected to cost $667 million, says the U.S. Army Corp of Engineers.

    Islands and shorelines in the Mid-Atlantic may become increasingly vulnerable to erosion. Sea levels are rising as the ocean warms and expands—and as glaciers and ice sheets melt—but the rise isn’t uniform around the planet. Currents, salinity, and topography create areas where sea levels are increasing more quickly, and recent research found that the U.S. Mid-Atlantic coast is one of the areas of accelerated sea-level rise. The rate of increase in the densely populated Mid-Atlantic is three to four times greater than average global sea-level rise. The increased sea level will make coastal regions and islands more prone to flooding and erosion.

    short animation of the Poplar Island restoration is available from the NASA Scientific Visualization Studio.

    1. References

    2. Burton, K. (n.d.) The island that almost vanished is slowly reappearing. U.S. Fish & Wildlife Service Chesapeake Bay Field Office. Accessed June 29, 2012.
    3. Erwin, M., Brinker, D.F., Watts, B.D., Costanzo, G.R., and Morton, D.D. (2010, September 1). Islands at bay: rising seas, eroding islands, and waterbird habitat loss in Chesapeake Bay (USA). Journal of Coastal Conservation.
    4. Kaplan, M.D.G. (2012, June 22). Escapes: Rebuilding Maryland’s wild islands. The Washington Post Accessed June 29, 2012.
    5. Sallenger Jr., A.H., Doran, K.S., and Howd, P.A. (2012, June 24). Hotspot of accelerated sea-level rise on the Atlantic coast of North America. Nature Climate Change.
    6. US Army Corps of Engineers Baltimore District. (2011, March 9). Poplar Island Paul S. Sarbanes Environmental Restoration Site. Accessed June 29, 2012.

    NASA Earth Observatory image by Robert Simmon, using Landsat data from the U.S. Geological Survey. Caption by Holli Riebeek.

    Instrument(s): Landsat 5 - TM
  8. Earth from the Moon

    Summer was approaching in the Northern Hemisphere on June 12, 2010, when the Lunar Reconnaissance Orbiter looked home to acquire this image. In orbit around the Moon, the orbiter was about 372,335 kilometers from Earth. Skies over the Middle East were clear, providing a cloud-free view of Arabian Peninsula and the mountains of Iran and Pakistan. Bright clouds stretch in a line from India northeast over the North Pacific Ocean. The other bright region in the image is the polar ice cap over the Arctic Ocean. The reference map provides a cloud-free view to illustrate Earth’s orientation in the image.

    The Lunar Reconnaissance Orbiter Camera captured this image as part of a calibration exercise. Like the human eye, the camera records reflected light. The cameras are among seven instruments that are mapping the surface of the Moon from the Lunar Reconnaissance Orbiter, which orbits 50 kilometers above the Moon. Mapping the Moon is a challenge because its color does not change greatly. Changes in rock types provide only small shifts in color. To make sure that the cameras are accurately recording small changes in reflected light, engineers look for a bright light against a dark background to provide a reference point. From the Moon, Earth is an ideal reference point to calibrate the cameras.

    The Narrow Angle Cameras—the cameras designed to capture the most detailed images of the Moon—took this image during calibration. The image is a mosaic of the views recorded by the Narrow Angle Camera Left and Narrow Angle Camera Right. The bottom of the Earth is clipped because the prediction of the exact time when the cameras’ fields of view would cross the Earth was off by a few seconds.

    1. Reference

    2. Robinson, M. (2010, June 24). The Earth from the Moon. Lunar Reconnaissance Orbiter Camera, NASA. Accessed July 30, 2010.

    Image courtesy NASA/Goddard/Arizona State University. Map by Robert Simmon. Caption by Holli Riebeek.

    Instrument(s): LRO - NAC
  9. Mississippi Meanders

    As it winds from Minnesota to the Gulf of Mexico, the Mississippi River is in constant flux. Fast water carries sediment while slow water deposits it. Soft riverbanks are continuously eroded. Floods occasionally spread across the wide, shallow valley that flanks the river, and new channels are left behind when the water recedes. This history of change is recorded in the Geological Investigation of the Alluvial Valley of the Lower Mississippi River, published by the Army Corps of Engineers in 1944.

    This map of an area just north of the Atchafalaya River shows a slice of the complex history of the Mississippi. The modern river course is superimposed on channels from 1880 (green), 1820 (red), and 1765 (blue). Even earlier, prehistoric channels underlie the more recent patterns. An oxbow lake—a crescent of water left behind when a meander (bend in the river) closes itself off—remains from 1785. A satellite image from 1999 shows the current course of the river and the old oxbow lake. Despite modern human-made changes to the landscape, traces of the past remain, with roads and fields following the contours of past channels.

    In the twentieth century, the rate of change on the Mississippi slowed. Levees now prevent the river from jumping its banks so often. The levees protect towns, farms, and roads near the banks of the river and maintain established shipping routes and ports in the Gulf of Mexico. The human engineering of the lower Mississippi has been so extensive that a natural migration of the Mississippi delta from its present location to the Atchafalaya River to the west was halted in the early 1960s by an Army Corps of Engineers project known as the Old River Control Structure (visible in the full-size Landsat image).

    The delta switching has occurred every 1,000 years or so in the past. As sediment accumulates in the main channel, the elevation increases, and the channel becomes more shallow and meandering. Eventually the river finds a shorter, steeper descent to the Gulf. In the 1950s, engineers noticed that the river’s present channel was on the verge of shifting westward to the Atchafalaya River, which would have become the new route to the Gulf. Because of the industry and other development that depended on the present river course, the U.S. Congress authorized the construction of the Old River Control Structure to prevent the shift from happening.

    Map courtesy the US Army Corps of Engineers, Landsat image by Robert Simmon, based on data from the UMD Global Land Cover Facility.

  10. Netherlands Dikes

    On the night of January 31, 1953, a combination of high spring tides and a strong windstorm caused the North Sea to surge onto coastal areas of the United Kingdom and the Netherlands, causing a major natural disaster. Thousands of lives were lost both on land and at sea. After the tragic event, the Netherlands undertook a major engineering project known as “Delta Works.” The project involved the fortification of seawalls, expansion of canals, and construction of dikes, dams, and locks.

    The southwestern coastline of the Netherlands, shown here, was especially vulnerable because it was composed of a series of islands crisscrossed with river outlets and estuaries. This image shows the results of the Delta Works project on the islands of the Netherlands southernmost coastal province, known as Zealand, which translates to “Sea Land.” Islands, once unconnected, are today linked by dikes and seawalls, and rivers and estuaries once open directly to the North Sea are enclosed as lakes.

    The patchwork of green, cream, and lavender colors on the islands shows the prevalence of agriculture in the province and fields in various stages of growth or harvest. The islands are cut through by the blue ribbons of canal, such as the Scheldt-Rhine Canal that flows into the image at lower right, cuts through Tholen Island and ends in the Krammer Strait. In the Eastern Scheldt Estuary, several light purple sandbars sit below the surface of the water. The high-resolution image shows ships in some of the canals and in the North Sea.

    This image was acquired on September 24, 2002, by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite. The full version of the scene covers an area of about 50.6 by 52.4 kilometers, and it is centered near 51.7 degrees North latitude, 4 degrees East longitude.

    Image courtesy NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team

  11. Looking Back from Apollo 11

    Forty-five years ago this week, two humans walked on the Moon for the first time. It was the achievement of their lives, and of so many of our lives on Earth. But amidst the excitement and hard work of landing so far from home, the Apollo 11 astronauts had many chances to look back at where they had come from. The famed Hasselblad 70 millimeter camera captured some of those moments.

    These two photographs were taken by the crew on their outbound journey from Earth to the Moon. Apollo 11 launched from Cape Canaveral at 9:32 a.m. on July 16, 1969, and these photos were captured that day. The top view shows the full disk of Earth, with bits of California, the Pacific Northwest coast, and Alaska peeking through the cloud cover in a scene otherwise dominated by the Pacific Ocean. The second, closer view shows more of the western United States and Canada, with the Rocky Mountains filling much of the center of the scene and the Arctic ice cap at the top.

    Unless you spend a lot of time looking at images from space—a pasttime that was in its infancy in the late 1960s—the view can be mysterious and disorienting sometimes. Reading through the transcripts of Apollo 11 communications, we can get some sense of the wonder, disorientation, and awe that Buzz Aldrin, Michael Collins, and Neil Armstrong must have felt while looking for navigation points or for simple beauty shots of their planet. About 51 minutes after launch, the conversation centered around lights in Earth’s atmosphere:

    Collins: Look at those bright ones down here.
    Aldrin: Lightning! Is that lightning out your window?
    Armstrong: No, I haven’t seen any lightning.
    Aldrin: Hell, that must be lightning. Either that or it’s the atmosphere.
    Armstrong: I just saw something. Maybe it is the atmosphere. They said that Borman’s [crew] could see it. They couldn’t hear it, but they could see it alright.

    About 30 minutes later, Collins looked down on a different, unfamiliar scene and noted: “It looks like trees and a forest or something. Looks like snow and trees. Fantastic. I have no conception of where we’re pointed or which way we are, but it’s a beautiful low-pressure cell out here.”

    Ten hours into the flight, Aldrin and astronaut Charlie Duke (working communications from Mission Control in Houston, Texas), had a conversation that sounds like a description of the images above. It was followed by some commentary between Armstrong and Duke.

    Aldrin: Hey, Charlie, I can see the snow on the mountains out in California, and it looks like LA doesn’t have much of a smog problem today.
    Duke: Roger, Buzz. Copy. Looks like there’s a good view out there then.
    Aldrin: Charlie, with the monocular, I can discern a definite green cast to the San Fernando Valley.
    Duke: How’s Baja California look, Buzz?
    Aldrin: Well, it’s got some clouds up and down it, and there’s a pretty good circulation system a couple of hundred miles off the west coast of California….Okay, Houston. You suppose you could turn the Earth a little bit so we could get a little bit more than just water?
    Duke: Roger, 11. I don’t think we got much control over that. Looks like you’ll have to settle for the water.

    To learn more about NASA’s celebration of the 45th anniversary of Apollo 11, click here.

    1. Reference

    2. NASA History Division (2011, March 29) The Apollo 11 Flight Journal. Accessed July 20, 2014.

    Astronaut photograph AS11-36-5339 was acquired on July 16, 1969, with a Hasselblad camera using a 250 millimeter lens. It is provided by the ISS Crew Earth Observations Facility and the Earth Science and Remote Sensing Unit, NASA Johnson Space Center. Astronaut photograph AS11-36-5302 was acquired on July 16, 1969, with a Hasselblad camera using an 80 millimeter lens and is provided by the Lunar and Planetary Institute. Both photos have been cropped and enhanced to improve contrast, and lens artifacts have been removed. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth. Caption by Mike Carlowicz.

    Instrument(s): Apollo
  12. Apollo 11 Launch Pad

    “I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely to the Earth,” President John F. Kennedy told a special joint session of Congress on May 25, 1961. Before the decade was out, on July 16, 1969, more than a million tourists gathered to watch the launch of Apollo 11, and millions more around the world watched the event on television. At 9:32 a.m. Eastern Daylight Time, Neil Armstrong, “Buzz” Aldrin, and Michael Collins began their journey to the Moon.

    Apollo 11 lifted off from launch pad 39A at Cape Canaveral, a headland along Florida’s Atlantic coast. On June 9, 2002, the Advanced Land Imager (ALI) on NASA’s Earth Observing-1 satellite captured this true-color image of launch pad 39A and neighboring pad 39B. Both launch pads sport networks of buff-colored roadways dissecting marshy fields. At the center of each launch pad, roads converge and support buildings cluster. Outside the launch pads, vegetation is deep green, thanks to the warm, humid local climate. Sunlight bounces off the rippling waves of the Atlantic Ocean, and illuminates the relatively smooth surfaces of the inland water bodies on the cape. A white wave breaks along the cape’s shore.

    By launching from the east coast of Florida, NASA took advantage of both geography and physics. Rockets could aim eastward and fly over the Atlantic Ocean, far away from heavily populated areas should anything go wrong. And within the continental United States, Florida is closest to the Equator. Launching from a locality close to the Equator enables the rocket to harness Earth’s orbital energy to boost its own trajectory.

    In mid-July 1969, the Apollo 11 astronauts left the pull of Earth’s gravity aboard a Saturn V rocket. Developed at Marshall Space Flight Center, the three-stage rocket was taller than a 36-storey building, and weighed 3,817 tons. All together, the rocket’s internal components—including gauges, sensors, switches, pumps, and fuel lines—numbered three million, and each piece had to work dependably. Spectators who assembled near Cape Canaveral (then named Cape Kennedy) felt the ground shake seconds after the rocket cleared the launch pad tower in a burst of flame and smoke. The first and second stages of the Saturn V sent the command module into a low-Earth orbit in less than 12 minutes. Two and a half hours later, the third-stage rocket placed Apollo 11 on its path to the Moon.

    1. References

    2. NASA. (2004, March 24). The Decision to Go to the Moon. Accessed July 15, 2009.
    3. NASA. (2005, September 8). Launch a “Rocket” from a Spinning “Planet.” Accessed July 15, 2009.
    4. NASA. (2007, November 22). NASA History Lesson – Launching from Kennedy Space Center – Past, Present and Future.Accessed July 15, 2009.
    5. NASA. (2009, July 14). Apollo 40th Anniversary. Accessed July 15, 2009.
    6. Smithsonian National Air and Space Museum. Saturn V: America’s Moon Rocket. Accessed July 15, 2009.
    7. Wilford, J.N. (2009, July 13). On Hand for Space History, as Superpowers Spar. The New York Times. Accessed July 15, 2009.

    NASA image by Robert Simmon, using ALI data distributed by the USGS Global Visualization Viewer. Caption by Michon Scott.

    Instrument(s): EO-1 - ALI
  13. The Golden-Brown State

    Now in its third year, the drought in California grows worse with each month. 2013 was the driest calendar year in 119 years of records, and 2014 has not brought much relief, even as scientists and residents wait hopefully for El Niño moisture. From stream gauges and reservoir levels to ground-based photos and satellite images, the landscape seems to grow browner and drier with each month.

    In a weekly report issued on July 17 by the U.S. Drought Monitor, the entire state of California was classified as being in severe drought. The situation was declared extreme for 79 percent of the state’s land area and exceptional in 36 percent. For more information on drought classification levels, read this.

    The pair of images above from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captures a wide view of the situation. The top image was acquired on June 25, 2014; the lower image shows the landscape on July 2, 2011, just as the latest dry period began. Turn on the image comparison tool to see the changes.

    Near the Pacific coast, some mountain forests are holding on, but much of area around the Coast Range has browned considerably. The green farmlands visible in the state’s Central Valley in 2011 are much less robust in 2014, with some lands dried out and many fields left fallow for lack of water. Just north of Yosemite National Park, the land is not only brown from drought; it is also scarred from the Rim Fire and other blazes in 2013.

    In the Sierra Nevada, the snow cover has decreased significantly, and what remains has a tan or gray tint from dust and soil. On April 1, 2014, California Department of Water Resources noted that snow-water content was just 32 percent of the historical average at a time when snow cover is usually at its yearly peak. By May 1, snow-water content was 18 percent of normal.

    This browning of California has been underway for quite some time, with precipitation averaging just 67 percent of normal over the past three years. According to the U.S. Drought Monitor and the National Climatic Data Center, the July 2013 to June 2014 period has been the warmest on record for the state and the third driest since 1895. Precipitation in the current water year (which started October 1, 2013) is just 56 percent of normal, and since May through September are typically dry even in normal years, drought relief is not likely any time soon.

    “Eleven of the past fifteen years have been drier than normal, with the past three years delivering about 45 percent of normal rain and snowpack in Southern California,” noted Bill Patzert, a climatologist at NASA’s Jet Propulsion Laboratory. “This follows two of the wettest decades in California’s history—the 1980s and 1990s—when population more than doubled and the economy of the state exploded. So that makes this drought more punishing than those in the past.”

    “The Amercian West and Southwest are definitely on the ropes,” Patzert added. “Even with a possible El Niño lurking in the tropical Pacific, there is no quick fix to this drought. It will take years of above-average rainfall to recover, and dramatic restrictions on water usage to maintain California’s economy. The time to tighten our water conservation belts is now.”

    1. References and Related Reading

    2. NASA (2014, February 25) NASA Responds to California’s Evolving Drought. Accessed July 17, 2014.
    3. NASA Earth Observatory (2014, January 18) All Dry on the Western Front.
    4. U.S. Drought Monitor (2014, July 17) National Drought Summary for July 15, 2014. Accessed July 17, 2014.
    5. U.S. Geological Survey California Water Science Center (2014, June 23) California Drought Information. Accessed July 17, 2014.

    NASA Earth Observatory images by Jesse Allen and Robert Simmon, using data from the Level 1 and Atmospheres Active Distribution System (LAADS). Caption by Michael Carlowicz.

    Instrument(s): Aqua - MODIS
  14. Typhoon Rammasun Making Landfall in China

    Three days after drenching the central Philippines in flooding rains, Typhoon Rammasun smashed into southeastern China and was still headed for northeastern Vietnam early on July 19, 2014. With a name meaning “thunder of God,” Rammasun approached the coast as a category 4 super typhoon and one of the strongest to hit China’s Hainan Province in 41 years.

    The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite acquired this image of Typhoon Rammasun at 1:35 p.m. local time (0535 UTC) on July 18, 2014. In the image, the storm has a well-defined eye situated just off the coast of northern Hainan; it is surrounded by bands of thunderstorms stretching across the South China Sea and the Gulf of Tonkin.

    Shortly before the image was captured, the Joint Typhoon Warning Center reported sustained winds of 125 knots (140 miles or 230 kilometers per hour) and maximum wave heights of 10 meters (35 feet). According to news reports, winds gusted to 160 kilometers (100 miles) per hour in Haikou City, Hainan, a city of 2 million people, and a month’s worth of rain fell in six hours. Chinese meteorologists warned of a storm surge of as much as 6 meters (20 feet). More than one million people were without power in Hainan and Guangdong, and hundreds of thousands of people were evacuated from low-lying areas.

    As typically happens when cyclones make landfall, Rammasun broke up a bit and lost strength earlier in the week after passing over the Philippines. But then the storm intensified rapidly over the warm waters of the South China Sea. Such evolution and intensification is a key interest of scientists participating in NASA’s Hurricane and Severe Storm Sentinel(HS3) airborne mission later this summer in the Atlantic Ocean.

    1. References and Related Reading

    2. Climate Central (2014, July 18) What’s Behind Typhoon Rammasun’s Rapid Intensification. Accessed July 18, 2014.
    3. NASA Hurricane Page (2014, July 18) Rammasun. Accessed July 18, 2014.
    4. South China Morning Post (2014, July 19) Severe damage and casualties as Super Typhoon Rammasun pummels southern China. Accessed July 18, 2014.
    5. U.S. Naval Observatory (2014) Joint Typhoon Warning Center. Accessed July 18, 2014.
    6. The Washington Post (2014, July 18) Destructive Super Typhoon Rammsun slams into southeast China. Accessed July 18, 2014.
    7. Xinhua (2014, July 18) Super typhoon Rammasun makes second landfall in China. Accessed July 18, 2014.

    NASA image by Jeff Schmaltz, LANCE/EOSDIS Rapid Response. Caption by Mike Carlowicz.

    Instrument(s): Aqua - MODIS
  15. The Peloponnese

    This photo from an astronaut on the International Space Station shows much of the nation of Greece. The urban region of Athens is recognizable due to its size and light tone compared to the surrounding landscape; the smaller cities of Megara and Lamia also stand out. Dark-toned mountains with snow-covered peaks contrast with warmer, greener valleys where agriculture takes place. The intense blue of the Mediterranean Sea fades near the Sun’s reflection point along the right side of the image, and numerous wind streaks in the lee of the islands become visible.

    The Peloponnese—home in ancient times to the city-state of Sparta—is the great peninsula separated from the mainland by the narrow isthmus of Corinth. Several times over the centuries these narrows have acted as a defensive point against attack from the mainland. More recently in 1893, the narrows provided a point of connection when a ship canal was excavated between the gulfs to the west and to the east.

    Astronaut photograph ISS039-E-3505 was acquired on March 21, 2014, with a Nikon D3S digital camera using a 28 millimeter lens, and is provided by the ISS Crew Earth Observations Facility and the Earth Science and Remote Sensing Unit, Johnson Space Center. The image was taken by the Expedition 39 crew. It has been cropped and enhanced to improve contrast, and lens artifacts have been removed. The International Space Station Program supports the laboratory as part of the ISS National Lab to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth. Caption by M. Justin Wilkinson, Jacobs at NASA-JSC.

    Instrument(s): ISS - Digital Camera