Tracking The Sun’s Cycles

They Put a Flag on the Moon

It’s 1969 and Apollo 11 astronauts Buzz Aldrin and Neil Armstrong are the first humans to land on the Moon. In now iconic footage, Aldrin and Armstrong carefully assemble and maneuver an American flag to place on the lunar surface. The fabric unfurls, staying suspended without any wind to animate the stars and stripes. The flagpole sways precariously as the crew work to anchor it in the Moon’s low gravity at just 1/6th that of Earth’s. How did this moment come about? On Flag Day, let’s dive behind-the-scenes of what led to getting the American flag on the Moon 50 years ago.

Image: Astronaut Buzz Aldrin poses for a photograph beside the deployed United States flag during the Apollo 11 mission.

Seeking to empower the nation, President John F. Kennedy gave us a grand charge. The human spaceflight program of the early 1960s was challenged to work on missions that sent humans to the surface of another world. Following President Kennedy’s death in 1963, President Richard Nixon stressed a more international perspective to the Apollo missions. To reconcile the need for global diplomacy with national interests, we appointed the Committee on Symbolic Activities for the First Lunar Landing.

Image: NASA Administrator Thomas Paine and President Richard Nixon are seen aboard the USS Hornet, Apollo 11’s splashdown recovery vessel.

The committee, and the U.S. at large, wanted to avoid violating the United Nations Outer Space Treaty, which prohibited any nation from taking possession of a celestial body. After some debate, they recommended that the flag only appear during the Apollo 11 spacewalk. A plaque would accompany it, explaining that the flag was meant to stand for peaceful exploration, not conquest. 

Image: The plaque reads “Here men from the planet Earth first set foot upon the Moon July 1969 A.D. We came in peace for all of mankind.” Under the text are signatures by President Nixon, Buzz Aldrin, Neil Armstrong, and Michael Collins.

A team of engineers at Johnson Space Center had three months to resolve several issues regarding the flag’s assembly. First, was the Moon’s lack of atmosphere. The flag, quite literally, could not fly the way it does on Earth. To address this, a horizontal crossbar was added to support the flag’s weight and give the illusion of it waving.

Image: NASA technician David L. McCraw shows the flag next to a Lunar Module mockup.

Second was the flag’s assembly, which had to be as lightweight and compact as possible so as not to take up limited storage space. The completed package, which was attached to Lunar Module’s ladder, weighed just under ten pounds. It received an outer case made of steel, aluminum, and Thermoflex insulation and blanketing to shield the flag from the 2,000 degree Fahrenheit spike from the Eagle’s descent engine.

Image: Component pieces of the flag assembly.

The last issue was mobility. Bulky spacesuits significantly restricted the astronauts’ range of motion, and suit pressurization limited how much force they could apply. To accommodate these limits, the team included telescoping components to minimize the need to reach and maneuver the poles. A red painted ring on the flagpole indicated how far into the ground it should be driven. Hinges and catches would lock into place once the pieces were fully extended.

Image: Diagram from the 1969 Apollo 11 press release illustrating astronaut spacesuit reach capabilities and ideal working height.

Fifty years after Apollo 11, the flag we planted on the lunar surface has likely faded but its presence looms large in United States history as a symbol of American progress and innovation.

Image: A close-up view of the U.S. flag deployed on the Moon at the Taurus-by the crew of Apollo 17, the most recent lunar landing mission.

The story doesn’t stop here. Anne Platoff's article “Where No Flag Has Gone Before” sheds more light on the context and technical process of putting the United States flag on the Moon. You can also check out Johnson Space Center’s recent feature story that details its presence in later missions. Happy Flag Day!  Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

Cassini Mission: What’s Next?

It’s Friday, Sept. 15 and our Cassini mission has officially come to a spectacular end. The final signal from the spacecraft was received here on Earth at 7:55 a.m. EDT after a fateful plunge into Saturn’s atmosphere.

After losing contact with Earth, the spacecraft burned up like a meteor, becoming part of the planet itself.

Although bittersweet, Cassini’s triumphant end is the culmination of a nearly 20-year mission that overflowed with discoveries.

But, what happens now?

Mission Team and Data

Now that the spacecraft is gone, most of the team’s engineers are migrating to other planetary missions, where they will continue to contribute to the work we’re doing to explore our solar system and beyond.

Mission scientists will keep working for the coming years to ensure that we fully understand all of the data acquired during the mission’s Grand Finale. They will carefully calibrate and study all of this data so that it can be entered into the Planetary Data System. From there, it will be accessible to future scientists for years to come.

Even beyond that, the science data will continue to be worked on for decades, possibly more, depending on the research grants that are acquired.

Other team members, some who have spent most of their career working on the Cassini mission, will use this as an opportunity to retire.

Future Missions

In revealing that Enceladus has essentially all the ingredients needed for life, the mission energized a pivot to the exploration of “ocean worlds” that has been sweeping planetary science over the past couple of decades.

Jupiter’s moon Europa has been a prime target for future exploration, and many lessons during Cassini’s mission are being applied in planning our Europa Clipper mission, planned for launch in the 2020s.

The mission will orbit the giant planet, Jupiter, using gravitational assists from large moons to maneuver the spacecraft into repeated close encounters, much as Cassini has used the gravity of Titan to continually shape the spacecraft’s course.

In addition, many engineers and scientists from Cassini are serving on the new Europa Clipper mission and helping to shape its science investigations. For example, several members of the Cassini Ion and Neutral Mass Spectrometer team are developing an extremely sensitive, next-generation version of their instrument for flight on Europa Clipper. What Cassini has learned about flying through the plume of material spraying from Enceladus will be invaluable to Europa Clipper, should plume activity be confirmed on Europa.

In the decades following Cassini, scientists hope to return to the Saturn system to follow up on the mission's many discoveries. Mission concepts under consideration include robotic explorers to drift on the methane seas of Titan and fly through the Enceladus plume to collect and analyze samples for signs of biology.

Atmospheric probes to all four of the outer planets have long been a priority for the science community, and the most recent recommendations from a group of planetary scientists shows interest in sending such a mission to Saturn. By directly sampling Saturn's upper atmosphere during its last orbits and final plunge, Cassini is laying the groundwork for an potential Saturn atmospheric probe.

A variety of potential mission concepts are discussed in a recently completed study — including orbiters, flybys and probes that would dive into Uranus' atmosphere to study its composition. Future missions to the ice giants might explore those worlds using an approach similar to Cassini's mission.

Learn more about the Cassini mission and its Grand Finale HERE.

Follow the mission on Facebook and Twitter for the latest updates.

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What are three things you would want everyone to know about your work?

Perfect 10: A Decade of Studying Ice from the Sky

From 2009 through 2019, our Operation IceBridge flew planes above the Arctic, Antarctic and Alaska, measuring the height, depth, thickness, flow and change of sea ice, glaciers and ice sheets.

IceBridge was designed to “bridge” the years between NASA’s two Ice, Cloud, and land Elevation Satellites, ICESat and ICESat-2. IceBridge made its final polar flight in November 2019, one year after ICESat-2’s successful launch.

A lot of amazing science happens in a decade of fundamentally changing the way we see ice. Here, in chronological order, are 10 of IceBridge’s most significant and exciting achievements.

2009: Go for launch

The first ICESat monitored ice, clouds, atmospheric particles and vegetation globally beginning in 2003. As ICESat neared the end of its life, we made plans to keep measuring ice elevation with aircraft until ICESat-2’s launch.

ICESat finished its service in August 2009, leaving IceBridge in charge of polar ice tracking for the next decade.

2009: Snow on sea ice

To measure how thick sea ice is, we first have to know how much snow is accumulated on top of the ice. Using a snow radar instrument, IceBridge gathered the first widespread data set of snow thickness on top of both Arctic and Antarctic sea ice.

2009: Getting to the bottom of glaciers 

IceBridge mapped hundreds of miles of grounding lines in both Antarctica and Greenland. Grounding lines are where a glacier’s bottom loses contact with the bedrock and begins floating on seawater – a grounding line that is higher than rock that the ice behind it is resting on increases the possibility of glaciers retreating in the future. 

The team mapped 200 glaciers along Greenland’s coastal areas, as well as coastal areas, the interior of the Greenland Ice Sheet and high-priority areas in Antarctica.

2011: Spotting cracks in the ice

While flying Antarctica in 2011, IceBridge scientists spotted a massive crack in Pine Island Glacier, one of the fastest-changing glaciers on the continent. The crack produced a new iceberg that October.

Pine Island has grown thinner and more unstable in recent decades, spawning new icebergs almost every year. IceBridge watched for cracks that could lead to icebergs and mapped features like the deep water channel underneath Pine Island Glacier, which may bring warm water to its underside and make it melt faster.

2013: Making a map of rock

Using surface elevation, ice thickness and bedrock topography data from ICESat, IceBridge and international partners, the British Antarctic Survey created an updated map of the bedrock beneath Antarctic ice.

Taking gravity and magnetic measurements helps scientists understand what kind of rock lies below the ice sheet. Soft rock and meltwater make ice flow faster, while hard rock makes it harder for the ice to flow quickly.

2013: Surprises under the ice

IceBridge’s airborne radar data helped map the bedrock underneath the Greenland Ice Sheet, revealing a previously unknown canyon more than 400 miles long and up to a half mile deep slicing through the northern half of the country.

The “grand canyon” of Greenland may have once been a river system, and today likely transports meltwater from Greenland’s interior to the Arctic Ocean.

2015: It’s what’s inside (the ice sheet) that counts

After mapping the bedrock under the Greenland Ice Sheet, scientists turned their attention to the middle layers of the ice. Using both ice-penetrating radar and ice samples taken in the field, IceBridge created the first map of the ice sheet’s many layers, formed as thousands of years of snow became compacted downward and formed ice.

Making the 3D map of Greenland’s ice layers gave us clues as to how the ice sheet has warmed in the past, and where it may be frozen to bedrock or slowly melting instead.

2018: Gap bridged!

ICESat-2 launched on September 15, 2018, rocketing IceBridge into the final phase of its mission: Connecting ICESat and ICESat-2.

IceBridge continued flying after ICESat-2’s launch, working to verify the new satellite’s measurements. By conducting precise underflights, where planes traced the satellite’s orbit lines and took the same measurements at nearly the same time, the science teams could compare results and make sure ICESat-2’s instruments were functioning properly.

2018: An impact crater under the ice

Using IceBridge data, an international team of scientists found an impact crater from a meteor thousands of years in the past. The crater is larger than the city of Washington, D.C., likely created by a meteor more than half a mile wide.

2019: Flying into the sunset

In 2019, IceBridge continued flying in support of ICESat-2 for its Arctic and Antarctic campaigns. The hundreds of terabytes of data the team collected over the decade will fuel science for years to come.

IceBridge finished its last polar flight on November 20, 2019. The team will complete one more set of Alaska flights in 2020.

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Meet Our Superhero Space Telescopes!

While the first exoplanets—planets beyond our solar system—were discovered using ground-based telescopes, the view was blurry at best. Clouds, moisture, and jittering air molecules all got in the way, limiting what we could learn about these distant worlds.

A superhero team of space telescopes has been working tirelessly to discover exoplanets and unveil their secrets. Now, a new superhero has joined the team—the James Webb Space Telescope. What will it find? Credit: NASA/JPL-Caltech

To capture finer details—detecting atmospheres on small, rocky planets like Earth, for instance, to seek potential signs of habitability—astronomers knew they needed what we might call “superhero” space telescopes, each with its own special power to explore our universe. Over the past few decades, a team of now-legendary space telescopes answered the call: Hubble, Chandra, Spitzer, Kepler, and TESS.

Much like scientists, space telescopes don't work alone. Hubble observes in visible light—with some special features (superpowers?)—Chandra has X-ray vision, and TESS discovers planets by looking for tiny dips in the brightness of stars.

Kepler and Spitzer are now retired, but we're still making discoveries in the space telescopes' data. Legends! All were used to tell us more about exoplanets. Spitzer saw beyond visible light into the infrared and was able to make exoplanet weather maps! Kepler discovered more than 3,000 exoplanets.

Three space telescopes studied one fascinating planet and told us different things. Hubble found that the atmosphere of HD 189733 b is a deep blue. Spitzer estimated its temperature at 1,700 degrees Fahrenheit (935 degrees Celsius). Chandra, measuring the planet’s transit using X-rays from its star, showed that the gas giant’s atmosphere is distended by evaporation.

Adding the James Webb Space Telescope to the superhero team will make our science stronger. Its infrared views in increased ranges will make the previously unseen visible.

Soon, Webb will usher in a new era in understanding exoplanets. What will Webb discover when it studies HD 189733 b? We can’t wait to find out! Super, indeed.

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How to Safely Watch the Aug. 21 Solar Eclipse

On Aug. 21, 2017, a solar eclipse will be visible in North America. Throughout the continent, the Moon will cover part – or all – of the Sun’s super-bright face for part of the day.

Since it’s never safe to look at the partially eclipsed or uneclipsed Sun, everyone who plans to watch the eclipse needs a plan to watch it safely. One of the easiest ways to watch an eclipse is solar viewing glasses – but there are a few things to check to make sure your glasses are safe:

 Glasses should have an ISO 12312-2 certification

They should also have the manufacturer’s name and address, and you can check if the manufacturer has been verified by the American Astronomical Society

Make sure they have no scratches or damage

To use solar viewing glasses, make sure you put them on before looking up at the Sun, and look away before you remove them. Proper solar viewing glasses are extremely dark, and the landscape around you will be totally black when you put them on – all you should see is the Sun (and maybe some types of extremely bright lights if you have them nearby).

Never use solar viewing glasses while looking through a telescope, binoculars, camera viewfinder, or any other optical device. The concentrated solar rays will damage the filter and enter your eyes, causing serious injury. But you can use solar viewing glasses on top of your regular eyeglasses, if you use them!

If you don’t have solar viewing glasses, there are still ways to watch, like making your own pinhole projector. You can make a handheld box projector with just a few simple supplies – or simply hold any object with a small hole (like a piece of cardstock with a pinhole, or even a colander) above a piece of paper on the ground to project tiny images of the Sun.

Of course, you can also watch the entire eclipse online with us. Tune into nasa.gov/eclipselive starting at noon ET on Aug. 21! 

For people in the path of totality, there will be a few brief moments when it is safe to look directly at the eclipse. Only once the Moon has completely covered the Sun and there is no light shining through is it safe to look at the eclipse. Make sure you put your eclipse glasses back on or return to indirect viewing before the first flash of sunlight appears around the Moon’s edge.

You can look up the length of the total eclipse in your area to help you set a time for the appropriate length of time. Remember – this only applies to people within the path of totality.

Everyone else will need to use eclipse glasses or indirect viewing throughout the entire eclipse!

Photographing the Eclipse

Whether you’re an amateur photographer or a selfie master, try out these tips for photographing the eclipse.  

#1 — Safety first: Make sure you have the required solar filter to protect your camera.

#2 — Any camera is a good camera, whether it’s a high-end DSLR or a camera phone – a good eye and vision for the image you want to create is most important.

#3 — Look up, down, and all around. As the Moon slips in front of the Sun, the landscape will be bathed in long shadows, creating eerie lighting across the landscape. Light filtering through the overlapping leaves of trees, which creates natural pinholes, will also project mini eclipse replicas on the ground. Everywhere you can point your camera can yield exceptional imagery, so be sure to compose some wide-angle photos that can capture your eclipse experience.

#4 — Practice: Be sure you know the capabilities of your camera before Eclipse Day. Most cameras, and even many camera phones, have adjustable exposures, which can help you darken or lighten your image during the tricky eclipse lighting. Make sure you know how to manually focus the camera for crisp shots.

#5 —Upload your eclipse images to NASA’s Eclipse Flickr Gallery and relive the eclipse through other peoples’ images.

Learn all about the Aug. 21 eclipse at eclipse2017.nasa.gov, and follow @NASASun on Twitter and NASA Sun Science on Facebook for more. Watch the eclipse through the eyes of NASA at nasa.gov/eclipselive starting at 12 PM ET on Aug. 21.

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Do you ever get to work along side people you use to look up to?

I did get a chance to work with some people that I really looked up to, and I was surprised by their generosity and giving me great advice. They’re busy people, and they spent hours giving me great advice. 

Heads-up, Earthlings! The annual Geminid meteor shower has arrived, peaking overnight Dec. 13-14. It's a good time to bundle up! Then, go outside and let the universe blow your mind!

The Geminids are active every December, when Earth passes through a massive trail of dusty debris shed by a weird, rocky object named 3200 Phaethon. The dust and grit burn up when they run into Earth's atmosphere in a flurry of "shooting stars." 

The Geminids can be seen with the naked eye under clear, dark skies over most of the world, though the best view is from the Northern Hemisphere. Observers will see fewer Geminids in the Southern Hemisphere, where the radiant doesn't climb very high over the horizon. Skywatching is easy. Just get away from bright lights and look up in any direction! Give your eyes time to adjust to the dark. Meteors appear all over the sky.

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Stars, Sea, and Smoke from the ISS: Tournament Earth 2021

We started Tournament Earth with 32 photos taken by astronauts from the Interantional Space Station and now we are down to 8. All of the #1 seeds are gone. Two #8 seeds are dominating their groups. Who will win? Let's take a closer look at the competitors still in the game. Then remember to vote for your favorites. The champion will be announced on April 13, 2021.

Stars in Motion vs. Cleveland Volcano

This matchup pits smoke against stars, but both have interesting stories.

The International Space Station (ISS) is constantly in motion. For astronaut photographers on board, that motion has consequences. For one, it makes it challenging to take photos. The same motion makes it possible to shoot spectacular photos like the one above. The image is compiled from a series of photographs taken by astronaut Don Pettit while he was onboard the ISS in April 2012. This composite was made from more than 72 individual long-exposure photographs taken over several minutes as the ISS traveled over the Caribbean Sea, across South America, and over the South Atlantic Ocean.

Astronaut Jeff Williams was the first to witness activity at the Cleveland Volcano on May 3, 2006. The Cleveland Volcano is one of the most active in the Aleutian Islands, which extend west-southwest from the Alaska mainland. It is a stratovolcano composed of alternating layers of hardened lava, compacted volcanic ash, and volcanic rocks. The event proved to be short-lived; two hours later, the plume had completely detached from the volcano. The ash cloud height could have been as high as 6,000 meters (20,000 feet) above sea level.

Stargazing from the ISS vs. Cruising Past the Aurora Borealis

This is the most stellar matchup of the tournament, literally. Two beloved star pictures face off in what will be one of the most difficult choices of the tournament.

An astronaut took this broad, short-lens photograph of Earth’s night lights while looking out over the remote reaches of the central equatorial Pacific Ocean. The ISS was passing over the island nation of Kiribati at the time, about 2600 kilometers (1,600 miles) south of Hawaii. Scientists identified the pattern of stars in the photo as our Milky Way galaxy (looking toward its center). The dark patches are dense dust clouds in an inner spiral arm of our galaxy; such clouds can block our view of stars toward the center. The curvature of the Earth crosses the center of the image and is illuminated by a variety of airglow layers in orange, green, and red.

Commonly known as the northern lights, these colorful ribbons of light appear to dance in the sky over the planet’s high latitudes, attracting sky chasers and photographers. Astronaut Randy “Komrade” Bresnik shot this photograph on September 15, 2017, as the space station passed over Ontario, Canada. Curtains of green—the most familiar color of auroras—dominate the light show, with hints of purple and red.

Rolling Through the Appalachians vs. Castellanus Cloud Tower

The Susquehanna River cuts through the folds of the Valley-and-Ridge province of the Appalachian Mountains in this photograph taken from the International Space Station by astronaut Christina Koch. The Valley-and-Ridge province is a section of the larger Appalachian Mountain Belt between the Appalachian Plateau and the Blue Ridge physiographic provinces. The northeast-southwest trending ridges are composed of Early Paleozoic sedimentary rocks. The valleys between them were made of softer rocks (limestone and shales) that were more susceptible to erosion; they are now occupied by farms.

An astronaut aboard the International Space Station took this photograph of a massive vertical cloud formation—known to meteorologists as cumulus castellanus—above Andros Island. The cloud name castellanus comes from the similarity to the crenellated towers or turrets of medieval castles. These clouds develop due to strong vertical air movement typically associated with thunderstorms.

Lake Van, Turkey vs. Typhoon Maysak from the Space Station

While orbiting on the International Space Station, astronaut Kate Rubins shot this photograph of part of Lake Van in Turkey, the largest soda or alkaline lake on Earth. Generally, soda lakes are distinguished by high concentrations of carbonate species. Lake Van is an endorheic lake—it has no outlet, so its water disappears by evaporation—with a pH of 10 and high salinity levels.

This photograph of super typhoon Maysak was taken by European Space Agency astronaut Samantha Cristoforetti as the International Space Station passed near the storm on March 31, 2015. The category 4 typhoon was headed for a possible landfall in the Philippines by the end of the week. It was unusual for the western Pacific to see such a strong storm so early in the year.

See all of the images and vote HERE. Follow @NASAEarth on social media for updates.

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From Microscopic to Multicellular: Six Stories of Life that We See from Space

Life. It's the one thing that, so far, makes Earth unique among the thousands of other planets we've discovered. Since the fall of 1997, NASA satellites have continuously and globally observed all plant life at the surface of the land and ocean. During the week of Nov. 13-17, we are sharing stories and videos about how this view of life from space is furthering knowledge of our home planet and the search for life on other worlds.

Earth is the only planet with life, as far as we know. From bacteria in the crevices of the deepest oceans to monkeys swinging between trees, Earth hosts life in all different sizes, shapes and colors. Scientists often study Earth from the ground, but some also look to our satellites to understand how life waxes and wanes on our planet.

Over the years, scientists have used this aerial view to study changes in animal habitats, track disease outbreaks, monitor forests and even help discover a new species. While this list is far from comprehensive, these visual stories of bacteria, plants, land animals, sea creatures and birds show what a view from space can reveal.

1. Monitoring the single-celled powerhouses of the sea

Known as the grass of the ocean, phytoplankton are one of the most abundant types of life in the ocean. Usually single-celled, these plant-like organisms are the base of the marine food chain. They are also responsible for the only long-term transfer of carbon dioxide from Earth’s atmosphere to the ocean. 

Even small changes in phytoplankton populations can affect carbon dioxide concentrations in the atmosphere, which could ultimately affect Earth’s global surface temperatures. Scientists have been observing global phytoplankton populations continuously since 1997 starting with the Sea-Viewing Wide Field-of View Sensor (SeaWiFS). They continue to study the small life-forms by satellite, ships and aircrafts.

2. Predicting cholera bacteria outbreaks

Found on the surface of zooplankton and in contaminated water, the bacteria that cause the infectious disease cholera — Vibrio cholerae — affect millions of people every year with severe diarrhea, sometimes leading to death. While our satellite sensors can’t detect the actual bacteria, scientists use various satellite data to look for the environmental conditions that the bacteria thrive in. 

Specifically, microbiologist Rita Colwell at the University of Maryland, College Park, and West Virginia University hydrologist Antar Jutla studied data showing air and ocean temperature, salinity, precipitation, and chlorophyllconcentrations, the latter a marker for zooplankton. Anticipating where the bacteria will bloom helps researchers to mitigate outbreaks.

Recently, Colwell and Jutla have been able to estimate cholera risk after major events, such as severe storms, by looking at satellite precipitation data, air temperature, and population maps. The two maps above show the team's predicted cholera risk in Haiti two weeks after Hurricane Matthew hit over October 1-2, 2016 and the actual reported cholera cases in October 2016.

3. Viewing life on land

From helping preserve forests for chimpanzees to predicting deer population patterns, scientists use our satellites to study wildlife across the world. Satellites can also see the impacts of perhaps the most relatable animal to us: humans. Every day, we impact our planet in many ways including driving cars, constructing buildings and farming – all of which we can see with satellites.

Our Black Marble image provides a unique view of human activity. Looking at trends in our lights at night, scientists can study how cities develop over time, how lighting and activity changes during certain seasons and holidays, and even aid emergency responders during power outages caused by natural disasters.

4. Tracking bird populations

Scientists use our satellite data to study birds in a variety of ways, from understanding their migratory patterns, to spotting potential nests, to tracking populations. In a rather creative application, scientists used satellite imagery to track Antarctica’s emperor penguin populations by looking for their guano – or excrement.

Counting emperor penguins from the ground perspective is challenging because they breed in some of the most remote and cold places in the world, and in colonies too large to easily count manually. With their black and white coats, emperor penguins are also difficult to count from an aerial view as they sometimes blend in with shadows on the ice. Instead, Phil Trathan and his colleagues at the British Antarctic Survey looked through Landsat imagery for brown stains on the sea ice. By looking for penguin droppings, Trathan said his team identified 54 emperor penguin colonies along the Antarctic coast.

5. Parsing out plant life

Just as we see plants grow and wilt on the ground, satellites observe the changes from space. Flourishing vegetation can indicate a lively ecosystem while changes in greenery can sometimes reveal natural disasters, droughts or even agricultural practices. While satellites can observe plant life in our backyards, scientists can also use them to provide a global picture. 

Using data from satellites including SeaWiFS, and instruments including the NASA/NOAA Visible Infrared Imaging Radiometer Suite and the Moderate Resolution Imaging Spectroradiometer, scientists have the most complete view of global biology to date, covering all of the plant life on land and at the surface of the ocean.

6. Studying life under the sea

Our satellites have helped scientists study creatures living in the oceans whether it’s finding suitable waters for oysters or protecting the endangered blue whale. Scientists also use the data to learn more about one of the most vulnerable ecosystems on the planet – coral reefs.

They may look like rocks or plants on the seafloor, but corals are very much living animals. Receiving sustenance from photosynthetic plankton living within their calcium carbonate structures, coral reefs provide food and shelter for many kinds of marine life, protect shorelines from storms and waves, serve as a source for potential medicines, and operate as some of the most diverse ecosystems on the planet.

However, coral reefs are vulnerable to the warming of the ocean and human activity. Our satellites measure the surface temperature of ocean waters. These measurements have revealed rising water temperatures surrounding coral reef systems around the world, which causes a phenomenon known as “coral bleaching.” To add to the satellite data, scientists use measurements gathered by scuba divers as well as instruments flown on planes.

During the week of Nov. 13-17, check out our stories and videos about how this view of life from space is furthering knowledge of our home planet and the search for life on other worlds. Follow at www.nasa.gov/Earth.

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