Tag Archives: National Aeronautics and Space Administration

Amusing Monday: Satellites can reveal “Earth as Art” imagery

The latest collection of “Earth as Art” satellite images shows stunning depictions of land, water and ice in both natural and unnatural colors.

Enhanced drone image of algae bloom in Milford Lake, Kansas. // Image: USGS/NASA Landsat

“Earth as Art #6,” produced by the U.S. Geological Survey, is the latest in a series of Landsat images released since 2001. This new series includes for the first time high-altitude photos taken by unmanned aircraft, or drones, as well as satellite depictions.

The satellites are designed to capture both visible and invisible light. The photos are often enhanced with color to provide extra contrast for scientists studying various aspects of the landscape. USGS officials post some of the more interesting images online, allowing the rest of us to see dynamic changes underway in river deltas, wetlands, ice fields, mountain ranges, deserts and more.

Some people choose to display these images in their homes, as they would works of art — and in some ways the true-life stories behind the pictures make them worthy of discussion beyond the beauty of the Earth itself.

Enhanced satellite image of Bangweulu Wetlands in Zambia. // Image: USGS/NASA Landsat

The first image on this page, titled “A Study in Algae,” reveals the annual algae bloom in Milford Lake, the largest man-made lake in Kansas at 15,700 acres. Because the algae can be harmful to fragile wetland ecosystems, the USGS Kansas Water Science Center uses drones with multispectral sensors to monitor changes in the blooms and report their effects on humans and animals.

In the second image, called “Wondrous Wetlands,” we are viewing the Bangweulu Wetlands in Zambia, where 17 rivers flow in but only one drains out. The entire wetlands, which are about the size of Connecticut, include areas dominated by grasslands as well as open water with shorelines featuring dense patches of aquatic vegetation.

All 20 of the newly featured images and their descriptions can be linked from the “Earth as Art #6” webpage. This series also can be downloaded in high-resolution format for framing or purchased as a print for $25 from the USGS Store.

Enhanced satellite image of Solway Firth between Scotland and England. // Image: USGS/NASA Landsat

Previous collections can be found on the “Earth as Art” webpage hosted by the USGS Earth Resources Observation and Science (EROS) Center. Near the bottom of this page, I’ve posted a new video, which adds music to a slideshow that features this latest collection.

If you don’t wish to wait for the next “Earth as Art” collection, you might like to peruse the “Image of the Week Gallery” sponsored by EROS. Beyond that is the “Landsat Image Gallery,” which includes the latest up-to-date images as well as many others posted since 1972.

The third and fourth images on this page, posted by EROS on Friday, show the Solway Firth along the coast of Dumfries and Galloway, Scotland, and Cumbria, England. The images, captured in October, provide a spectacular example of a drama that plays out in many estuaries during tidal changes.

Zooming out from above image to view surrounding landscape. // Image: USGS/NASA Landsat

“This sloshing of water into and out of basins can produce visible surges of sediment and floating debris, turbulent mixing of fresh and salty waters, and sometimes distinct lines between different water masses,” states the description on the image page. “The water changes color abruptly offshore where the shallower bay meets deeper waters of the Irish Sea.”

Blending art and science, Norman Kuring of NASA’s Ocean Biology group used software programs with color-filtering aspects to draw out the fine details in the water. The swirls and streamers are real, but the tones are enhanced to better show the sediments and dissolved organic matter. To see the natural colors, go to this lower-resolution image.

Also shown in these images captured by Landsat 8 is the Robin Rigg wind farm, located on a sandy shoal and revealed as a symmetrical pattern of white dots and shadows. Robin Rigg is Scotland’s first offshore wind farm, coming online in 2010. It can generate up to 174 megawatts of power, enough to supply 117,000 homes, according to the USGS summary.

In November, the USGS released a new report placing the economic value of the Landsat archive at about $3.45 billion in 2017, compared to $2.19 billion in 2011.

“The analysis is based on the number of scenes downloaded from the USGS and the price that users would be willing to pay per scene,” according to a summary of the report. “It does not include scenes downloaded by cloud vendors or other downstream economic benefits for things such as value-added products and environmental monitoring.”

The report also concludes that much of the value of the Landsat images comes from the open-data policy of allowing users to access as much or as little of the imagery they need. Despite the reported value to users, charging fees per image would likely result in a major decrease in their use, the report says.

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Amusing Monday: To survive, penguins have adopted odd behaviors

One of the strangest animals on Earth is the emperor penguin, a bird that exhibits some remarkable behaviors to help it survive under the harshest conditions.

One might wish that the penguins would fly away to a warmer area when the frigid cold of winter strikes the Antarctic each year, but this bird doesn’t fly at all. Instead, groups of penguins huddle together on open ice during the long winters. They take turns moving into the middle of the group to escape the worst of the chill winds and to warm up just a little.

Females lay a single egg and quickly abandon it, leaving the males to care for the egg while the females go hunting. For up to two months, the males will balance the egg on their feet, keeping the egg warm in a feathery “brood pouch.” During this time, the males will eat nothing while the females travel many miles to the sea to gorge themselves on fish, squid and krill. When the females return, they are ready to feed their newborn chicks some of this partially digested food, while the males are free to go and find food for themselves.

While these unusual birds can’t fly, their skills under water are quite amazing — and amusing. Their unique physiology allows them to dive much deeper than any other water bird, stay under water for more than 20 minutes, and eventually zoom back to the surface at an incredible rate, as shown in the first video on this page.

Continue reading →

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Farewell to Cassini, which found wondrous worlds not so far away

I’d like to take a moment to celebrate the discoveries of NASA’s Cassini spacecraft — including the finding of water on Saturn’s moons Titan and Enceladus.

Water vapor escapes from geothermal vents on Saturn’s moon Enceladus. // Photo: NASA

The 13-year mission ended Friday when Cassini, running out of fuel, was directed to self-destruct by burning up in the atmosphere of the ringed planet.

“This is the final chapter of an amazing mission, but it’s also a new beginning,” Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate, said in a story on NASA’s website. “Cassini’s discovery of ocean worlds at Titan and Enceladus changed everything, shaking our views to the core about surprising places to search for potential life beyond Earth.”

Cassini was launched from Florida’s Cape Canaveral in 1997 and reached Saturn in 2004. NASA extended the mission for two years and then again for seven years, as new findings continued to emerge, with a later focus on Saturn’s moons. An amazing surprise came when a subsurface ocean was found on Enceladus.

“Cassini may be gone, but its scientific bounty will keep us occupied for many years,” said Linda Spilker, Cassini project scientist at NASA’s Jet Propulsion Laboratory. “We’ve only scratched the surface of what we can learn from the mountain of data it has sent back over its lifetime.”

The video on this page reveals some of the feelings that welled up and lingered among the Cassini team after the spacecraft came to its fiery end on Friday.

If you are interested in space discoveries, I recommend a glance at the text, photos and videos shared on NASA’s website. I also enjoyed the “most inspiring, beautiful, and historic” photos taken during the mission and pulled together by Brian Resnick for Vox Media’s website.

As Linda Spilker aptly described it, “Things never will be quite the same for those of us on the Cassini team now that the spacecraft is no longer flying. But we take comfort knowing that every time we look up at Saturn in the night sky, part of Cassini will be there, too.”

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Amusing Monday: Satellite captures images that could pass for art

Landsat 8, an American observation satellite, was launched four years ago. Since May of this year, the satellite has recorded more than a million images.

Puget Sound, Aug. 27
Photo: U.S. Geological Survey

As one might expect, satellite images of the same place vary over time, considering that clouds, smoke, vegetation and geological phenomena alter the appearance of the Earth’s surface. You can see some differences in the pictures of Puget Sound on this page. The first was taken on Aug. 27 and the second on Sept. 7. The third picture, taken on Dec. 18, 2016, shows Mount Rainier in the lower portion of the photo with Puget Sound in the upper part.

Puget Sound, Sept. 7
Photo: U.S. Geological Survey

In some areas, the Landsat photos are so intriguing that they have been compared to works of art. Staffers at Live Science, an online magazine, chose 73 images to share with their readers. See their full collection of “Artistic Views of Earth from Above” at Live Science. I’ve picked some of my favorites and shown them below.

Mount Rainier, Dec. 18, 2016
Photo: U.S, Geological Survey

If you are interested, you can go to the source of the Landsat images, managed by the U.S. Geological Survey. I used a program called EarthExplorer to find the images of Puget Sound and Mount Rainier. Another search engine, LandsatLook Viewer, lets you zoom in on an area of North America or other continents to obtain satellite images. A third approach is GloVis, with its multiple filters to narrow your search.

The datasets are a collaboration between NASA, which developed and launched the satellite, and the USGS, which developed the ground systems for processing and sharing the data.

Following are four of the “artistic views” researched and provided by Live Science, which today is offering 73 fascinating photos of Hurricane Irma.

Putrid Sea // Photo: USGS

Putrid Sea: The various colors formed in a cluster of lagoons on the Crimean Peninsula provides an interesting painting, but the area has a reputation for foul odors caused by the algae that gives the water its color. The proper name of the area is Syvash, but some call it the Putrid Sea. The Syvash is part of the disputed area controlled by Ukraine until Russia sent in troops to annex the area in 2014.

Canyonlands // Photo: USGS

Canyonlands: Yellows, browns and blue characterize Canyonlands National Park in Utah, where the Green and Colorado rivers come together. The rocky and dry area of the park features unique geologic features, including steep canyons, eroded arches and interesting rock formations as well as ancient Native American rock paintings. The blue area in the photo is the peak of Mount Waas. Author Edward Abbey called the Canyonlands “the most weird, wonderful, magical place on Earth — there is nothing else like it anywhere.”

Eye of Quebec // Photo: USGS

Eye of Quebec: One of the Earth’s largest and oldest known craters was formed by the impact of a three-mile-wide meteor some 214 million years ago, experts say. The resulting Canadian lake, Lake Manicouagan, has been called the Eye of Quebec. The original crater was about 62 miles across, but erosion and deposition of sediments has reduced that to about 45 miles today. The island in the center of the lake is known as René-Levasseur Island. I suspect the purple image is produced by selecting one region of the light spectrum.

Green on Blue // Photo: USGS

Green on blue: The swirls of green and blue in the picture are largely phytoplankton floating in the Bering Sea, the body of water that separates Alaska from Russia. The plankton typically grow when there is an abundance of sun and nutrients, often reaching their peak at the end of summer. This photo, taken on Sept. 22, 2014, shows a few scattered white clouds dotting the sky.

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Amusing Monday: Playing with water in the weightlessness of space

Since the beginning of the manned space program, astronauts have been playing with water in microgravity conditions. The result has been a large assortment of videos demonstrating the unique and amusing properties of water.

In the first video on this page, Chris Hadfield, an astronaut with the Canadian Space Agency demonstrates what happens aboard the International Space Station when you ring out a soaked wash cloth in the weightlessness of space.

The experiment was suggested by students Kendra Lemke and Meredith Faulkner of Lockview High School in Fall River, Nova Scotia. It was posted on YouTube in 2013.

The video shows that the surface tension of water is great enough that the water keeps clinging when Hadfield rings out the cloth. If you watch closely, however, you can see a few droplets fly off when he starts to ring out the cloth.

Continue reading →

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Hood Canal changes color from growth of white plankton

Hood Canal cloaked in light green from heavy plankton growth. NASA image: Jeff Schmaltz, LANCE/EOSDIS Rapid Response
Hood Canal cloaked in light green from heavy plankton growth.
NASA image: Jeff Schmaltz, LANCE/EOSDIS Rapid Response

From space, Hood Canal is easily recognized by its new shade of bimini green, a color that stands out clearly from the rest of Puget Sound and the Pacific Ocean, as shown in the photo above.

The color is caused by a large bloom of coccolithophore, a single-celled phytoplankton bearing a shell made of white calcium carbonate.

A more detailed image of the plankton bloom. NASA image: Jesse Allen, using Landsat data from USGS
A more detailed image of the plankton bloom.
NASA image: Jesse Allen, with Landsat data from USGS

Teri King of Washington Sea Grant spotted the unusual color more than a week ago from the ground while driving along Hood Canal.

“I thought to myself, ‘Am I dreaming of the Cayman Islands?’” she reported on her Facebook page. “I pulled over to the side and took a few photos to document my observations. I then had an opportunity to grab a water sample. Yep, a Coccolithophore bloom from Quilcene to Lilliwaup.

“It is hard to miss a bloom of this color,” Teri continued on Facebook. “We don’t see them often, but when we do it is remarkable. The water takes on a tropical blue green appearance with white speckles.”

Scanning electron micrograph of plankton Emiliania huxleyi
Scanning electron micrograph of plankton Emiliania huxleyi
Image: Alison R. Taylor, U. of North Carolina Wilmington

The photo from space (top) was taken last Sunday from NASA’s Aqua satellite with equipment used to capture the natural color. On Wednesday, a more detailed image (second photo) was taken from the Landsat 8 satellite.

Reporter Tristan Baurick describes the phenomenon in yesterday’s Kitsap Sun. The single-celled plankton are not harmful to people or animals, so the bloom won’t affect shellfish harvesting. Hood Canal, as we’ve discussed many times, is prone to low-oxygen conditions, often exacerbated by massive blooms of plankton, which reduce oxygen through the process of decay.

The last major bloom of this kind in Hood Canal was noted in northern Hood Canal during the summer of 2007. Samples taken at that time showed the species of coccolithophorid to be Emiliania huxleyi, according to a report for the Hood Canal Dissolved Oxygen Program.

NASA’s photos and description of the latest bloom can be found on the Earth Observatory website, which also includes just about all you need to know about coccolithophores.

Hood Canal is green alright, up close and far away. Photo: Meegan M. Reid, Kitsap Sun
Hood Canal is green alright, up close and far away.
Photo: Meegan M. Reid, Kitsap Sun

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Amusing Monday: I’m learning my ABCs and something about Earth

Adam Volland of NASA’s Earth Observatory program came up with an interesting idea. Looking over satellite images, Adam has found every letter of the alphabet formed by Earthly features, mostly land-based formations.

Letter B

He calls it “Reading the ABCs from Space.”

Whoever knew that Holla Bend National Wildlife Refuge in Arkansas forms the letter “B” if you include a nearby section of the Arkansas River?

He found the letter “C” in a man-made island in the southern part of Bahrain, an island country in the Persian Gulf.

What I also like about Adam’s project is the narrative he has written about each letter, describing the names of relevant features, animals and objects that start with the particular letter, including links to learn more about those features.

Letter C

Here’s what he wrote for the letter “Z”: “What begins with Z? Zenith and zooplankton. Zillions of smoke particles zipping, zooming and zigzagging above Canada!”

And it all ties together, since Adam’s Z is an image of wildfire smoke over Canada. As the caption explains (and all images are explained), the image for “Z” was captured with a “moderate resolution imaging spectroradiometer” (MODIS) on NASA’s Aqua satellite.

Letter Z

Considering all the associated links, this was a big project to create. It is also a great way to organize a lot of educational material. It reminds me of when I was in junior high school and decided to read the entire “World Book Encyclopedia.” I started at the beginning of the first book, a thick one that contained all the “A” words. I read for an hour or two each night after doing my regular homework. After many weeks, I was about halfway through the “A” words before I shifted my attention to other reading materials.

I’m sure it won’t take nearly as long to read through Adam’s letters and all the linked materials. I’ve begun reading “The ABCs from space” with the letter “A” and expect to learn a lot about things on Earth.

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A unique view of Earth, as seen from the moon

Photo: NASA
Photo: NASA

When I saw this amazing photo of our water planet, I knew I had to share it with readers of this blog. NASA is offering a high-resolution image (click to enlarge) on its website.

The composite photo was taken from NASA’s Lunar Reconnaissance Orbiter, which orbits the moon and can see the Earth rising and setting above the moon’s horizon.

“The image is simply stunning,” said Noah Petro, deputy project scientist for LRO at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “The image of the Earth evokes the famous ‘Blue Marble’ image taken by Astronaut Harrison Schmitt during Apollo 17, 43 years ago, which also showed Africa prominently in the picture.”

His comments and other information are provided in a NASA news release.

LRO experiences 12 Earthrises every day, but its instruments are normally focused on the lunar surface. Images of Earth are captured rarely when LRO’s camera is turned away from the moon to study the extremely thin lunar atmosphere or to make calibration adjustments, according to the news release, which explains the entire process.

The image above was composed from a series of photos taken Oct. 12, when the spacecraft was about 83 miles above the farside of the moon.

Astronauts on the moon can never see the Earth rise or set. Since the moon revolves around its axis at the same rate as its rotation around the Earth, it always appears in the same spot in the moon’s sky. That location varies by where the observer is standing on the moon’s surface, and there is no Earth visible from the farside of the moon. Where the Earth is visible, the view of the planet is constantly changing, as continents rotate into view — unlike the view of the moon’s surface from Earth, which never changes.

NASA’s first Earthrise image was taken with the Lunar Orbiter 1 spacecraft in 1966. Perhaps NASA’s most iconic Earthrise, according to NASA, was taken by the crew of Apollo 8 on Christmas Eve in 1968.

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NASA researchers measure sea levels, predict faster rise

A new worldwide map of sea level rise, plotted with precision satellite instruments, shows that the Earth’s oceans are rising faster with no end in sight.

Sea levels have gone up an average of 3 inches since 1992, with some locations rising as much as 9 inches. Meanwhile, some limited areas — including the West Coast — have experienced declining sea levels for various reasons.

Sea level change over 22 years. Map: NASA
Sea level change over 22 years. (Click to enlarge) // Map: NASA

Two years ago, climatologists released an international consensus, which predicted a sea-level rise of between 1 and 3 feet by the end of this century. It was a conservative estimate, and new evidence suggests that ocean waters are likely to meet or exceed the top of that range, possibly going much higher, according to four leading researchers speaking at a news conference yesterday.

The implications are huge and growing more important all the time. At a minimum, waterfront property owners and shoreline planners need to begin taking this into consideration. It doesn’t make sense to build close to the shoreline if extreme high tides will bring seawater to one’s doorstep.

If we hope to avoid local extinctions of key intertidal species, we must start thinking about how high the waters will be in 50 to 100 years.

For clues to the future, we can watch Florida, where vast areas stand at low elevations. Even now, during high tides, Miami is beginning to see regular flooding in areas that never got wet before. This is the future of low-lying areas in Puget Sound, such as estuaries. In the Pacific ocean, the threat of inundating complete islands is becoming very real.

Along the West Coast, sea levels have actually declined over the past 20 years, largely because of the cooling effect of the Pacific Decadal Oscillation, a warming/cooling cycle that can remain in one phase for decades. The cycle appears to be shifting, with the likely effect that sea levels on the West Coast will soon rise as fast or faster than the worldwide average, according to Josh Willis, an oceanographer at NASA’s Jet Propulsion Laboratory in Pasadena, Calif.

Global sea level has been measured accurately and continuously by satellites since 1993. Graphic: Steve Nerem, University of Colorado
Global sea level has been measured accurately and continuously by satellites since 1993.
Graphic: Steve Nerem, University of Colorado

The cause of sea level rise is attributed to three factors. Scientists estimate that roughly one-third of the rise is caused by thermal expansion of ocean waters, which absorb much of the energy from global warming. Another third comes from the melting of the massive Greenland and Antarctic ice sheets. The remaining third comes from the melting of mountain glaciers throughout the world. Researchers at yesterday’s news conference said they expect the melting to accelerate.

Measuring the change in sea-level rise has become possible thanks to advanced technology built into altimeters carried aboard satellites. The instruments can distinguish changes in elevation as small as one part in 100 million.

“The instruments are so sensitive that if they were mounted on a commercial jetliner flying at 40,000 feet, they could detect the bump caused by a dime lying flat on the ground,” said Michael Freilich, director of NASA’s Earth Science Division.

While sea level rise can now be measured, predicting the rate of future rise is difficult, because much of the melting by ice sheets occurs out of sight under the water.

The Greenland ice sheet covers 660,000 miles — nearly the size of Alaska. Satellite measurements have shown that an average of 303 gigatons of ice have melted each year over the past decade. The Antarctic ice sheet has lost an average of 118 gigatons per year, but some new studies suggest it could begin to melt much faster.

In Greenland, researchers are reporting that one of the largest chunks of ice ever to break away from land cleaved from the Jakobshavn glacier in a “calving” event that left researchers awestruck. More than 4 cubic miles of ice was loosed quickly into the sea. Check out the news release by the European Space Agency.

“This is a continuing and evolving story,” glaciologist Eric Rignot said during yesterday’s news conference. “We are moving into a set of processes where we have very tall calving cliffs that are unstable and start fracturing and break up into icebergs …

“We have never seen something like this on that scale before,” said Rignot, associated with JPL and the University of California at Irvine. “Personally, I am in awe at seeing how fast the icefall, the calving part of the glacier, is retreating inland year by year.”

Other new information from NASA, including lots of graphics:

    • The following video tells the basic story about sea level rise.

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    Mountains of Pluto
    may be formed on ‘bedrock’ of water-ice

    Finding “youthful” mountains on the surface of Pluto has come as a great surprise to the Geology, Geophysics and Imaging (GGI) team studying the distant body since the New Horizons spacecraft flew past.

    This image of mountains was taken by New Horizons just 1.5 hours before the spacecraft's closest approach to Pluto. Image Credit: NASA-JHUAPL-SwRI
    This image of mountains was taken by New Horizons just 1.5 hours before the spacecraft’s closest approach to Pluto. // Image Credit: NASA-JHUAPL-SwRI

    I was not planning to write anything about Pluto. After all, this blog is about water. Water on Mars is one thing. I did not expect to find relevance to a dwarf planet covered in frozen methane and frozen nitrogen.

    But I can’t ignore the findings of scientists who studied images from New Horizons to announce a discovery of mountains rising as high as 11,000 feet and a region near Pluto’s equator that may still be geologically active. This conclusion comes from a lack of craters on the surface, said GGI team leader Jeff Moore of NASA’s Ames Research Center in Moffett Field, Calif.

    One would expect that Pluto would be scarred from all the space debris falling to the surface over billions of years — unless recent geologic activity had erased the pockmarks, according to a report posted today by NASA.

    “This is one of the youngest surfaces we’ve ever seen in the solar system,” Moore said.

    Pluto has practically no gravitational interaction with another planetary body, which is believed to be why mountains have risen on the moons of giant planets. On Pluto, other forces must be at play.

    “This may cause us to rethink what powers geological activity on many other icy worlds,” said GGI deputy team leader John Spencer of the Southwest Research Institute in Boulder, Colo.

    The mountains are likely made of a water-ice “bedrock,” because frozen methane and frozen nitrogen are not strong enough to form mountains, the researchers say.

    “At Pluto’s temperatures, water-ice behaves more like rock,” said deputy GGI lead Bill McKinnon of Washington University in St. Louis.

    The scientists have been waiting nine years for New Horizons to reach Pluto, and now it is over. Yesterday, the spacecraft zoomed by at 30,800 miles per hour while seven instruments collected all sorts of information. Now all those data will be analyzed and discussed, adding to our knowledge of the solar system and beyond.

    One mystery solved is the Pluto’s actual size — 1,473 miles in diameter — somewhat smaller than many earlier estimates. Pluto’s atmosphere complicated the estimates.

    “The size of Pluto has been debated since its discovery in 1930,” McKinnon said in a report from NASA. “We are excited to finally lay this question to rest.”

    The size revision means that Pluto is less dense than presumed earlier. The amount of ice in the interior is greater, and the lowest layer of the atmosphere — the troposphere — is shallower that once believed.

    Pluto’s largest moon, Charon, lacks a significant atmosphere, so observations from New Horizons confirms previous estimates of 751 miles across.

    The next two smaller moons were too small for researchers to estimate their size until now. Hydra appears to be about 30 miles in diameter, and Nix is about 20 miles across. Mission scientists believe that ice may be making their surfaces extra bright.

    Pluto’s two smallest moons, Kerberos and Styx, are harder to measure but researchers expect to make estimates later.

    Pluto and its largest moon, Charon, shown just above the Earth's surface in this graphic. Graphic: John Hopkins University APL
    Pluto and its largest moon, Charon, placed just above the Earth’s surface in this graphic to show their relative sizes.
    John Hopkins University Applied Physics Laboratory

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