Will Perseverance Be Near Any Other Rovers?

What's next for NASA? In 2019, we’re once again preparing for human missions to the Moon. We're keeping the promise by developing new systems and spacecraft, making innovations in flight and technology, living and doing science on the International Space Station, and delivering images and discoveries from our home planet, our solar system and beyond.

Check out What’s Next for NASA: https://www.nasa.gov/next

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Solar System: Things to Know This Week

Jupiter, we've got quite the photoshoot planned for you. Today, our Juno spacecraft is flying directly over the Great Red Spot, kicking off the first-ever close-up study of this iconic storm and passing by at an altitude of only 5,600 miles (9,000 kilometers). In honor of this historic event, below are 10 things to know about the planet's most famous feature.

1. A Storm That Puts Others to Shame

The Great Red Spot is a gigantic, high-pressure, ancient storm at Jupiter's southern hemisphere that's one of the longest lasting in the solar system. It's so large, about 1.3 Earths could fit inside of it. And you can bet you'll get swept away—the storm's tumultuous winds peak at about 400 mph.

2. How Old Is It? 

The Great Red Spot has been swirling wildly over Jupiter's skies for the past 150 years—maybe even much longer. While people saw a big spot on Jupiter when they started stargazing through telescopes in the 1600s, it's still unclear whether they were looking at a different storm. Today, scientists know the Great Red Spot has been there for a while, but they still struggle to learn what causes its swirl of reddish hues.

3. Time for That Close-Up 

Juno will fly over the Great Red Spot about 12 minutes after the spacecraft makes the closest approach to Jupiter of its current orbit at 6:55 p.m. on July 10, PDT (9:55 p.m. on July 10, EDT; 1:55 a.m. on July 11, Universal Time). Juno entered orbit around Jupiter on July 4, 2016.

4. Oh, So Mysterious 

Understanding the Great Red Spot is not easy, and it's mostly Jupiter's fault. The planet a thousand times as big as Earth and consists mostly of gas. A liquid ocean of hydrogen surrounds its core, and the atmosphere consists mostly of hydrogen and helium. That translates into no solid ground (like we have on Earth) to weaken storms. Also, Jupiter's clouds make it hard to gather clear observations of its lower atmosphere. 

This false-color image of Jupiter was taken on May 18, 2017, with a mid-infrared filter centered at a wavelength of 8.8 microns, at the Subaru Telescope in Hawaii, in collaboration with observations of Jupiter by NASA's Juno mission. Credit: NAOJ/NASA/JPL-Caltech

5. Help From Hawaii 

To assist Juno's investigation of the giant planet's atmosphere, Earth-based telescopes lent their helpful eyes. On May 18, 2017, the Gemini North telescope and the Subaru Telescope—both located on Hawaii's Mauna Kea peak—simultaneously examined Jupiter in very high resolutions at different wavelengths. These latest observations helped provide information about the Great Red Spot's atmospheric dynamics at different depths and at other regions of Jupiter.

6. Curious Observations 

Observations from Subaru showed the Great Red Spot "had a cold and cloudy interior increasing toward its center, with a periphery that was warmer and clearer," said Juno science team member Glenn Orton of our Jet Propulsion Laboratory, Pasadena, California. "A region to its northwest was unusually turbulent and chaotic, with bands that were cold and cloudy, alternating with bands that were warm and clear."

This composite, false-color infrared image of Jupiter reveals haze particles over a range of altitudes, as seen in reflected sunlight. It was taken using the Gemini North telescope in Hawaii on May 18, 2017, in collaboration with observations of Jupiter by our Juno mission. Credits: Gemini Observatory/AURA/NSF/NASA/JPL-Caltech

7. Hot in Here 

Scientists were stumped by a particular question: Why were the temperatures in Jupiter's upper atmosphere comparable to those found at Earth, even though Jupiter is more than five times the distance from the sun? If the sun isn't the heat source, then what is? Turns out, the storm in the Great Red Spot produces two kinds of turbulent energy waves that collide and heat the upper atmosphere. Gravity waves are much like how a guitar string moves when plucked, while acoustic waves are compressions of the air (sound waves). Heating in the upper atmosphere 500 miles (800 kilometers) above the Great Red Spot is thought to be caused by a combination of these two wave types "crashing," like ocean waves on a beach.

8. Color Theory 

Scientists don't know exactly how the Great Red Spot's rich colors formed. Studies predict Jupiter's upper atmosphere has clouds consisting of ammonia, ammonium hydrosulfide, and water, but it's still unclear how or even whether these chemicals react. "We're talking about something that only makes up a really tiny portion of the atmosphere," said Amy Simon, an expert in planetary atmospheres at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "That's what makes it so hard to figure out exactly what makes the colors that we see." Over at NASA's Jet Propulsion Laboratory in Pasadena, California, researchers concluded that the ruddy color is likely a product of simple chemicals being broken apart by sunlight in the planet's upper atmosphere. "Our models suggest most of the Great Red Spot is actually pretty bland in color, beneath the upper cloud layer of reddish material," said Kevin Baines, a Cassini scientist at JPL.

9. Been There, Haven't Seen That 

In January and February 1979, NASA's Voyager 1 spacecraft zoomed toward Jupiter, capturing images of the Great Red Spot during its approach. Still, we've never been as close as we're about to get during Juno's flyover on July 10.

10. Simply Beautiful 

This image of a crescent Jupiter and the iconic Great Red Spot was created by a citizen scientist, Roman Tkachenko, using data from Juno's JunoCam instrument. JunoCam's raw images are available here for the public to peruse and enhance.Want to learn more? Read our full list of the 10 things to know this week about the solar system HERE.

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What kind of math is needed to get to Mars? How is the path of the lander calculated?

Navigating Space by the Stars

A sextant is a tool for measuring the angular altitude of a star above the horizon and has helped guide sailors across oceans for centuries. It is now being tested aboard the International Space Station as a potential emergency navigation tool for guiding future spacecraft across the cosmos. The Sextant Navigation investigation will test the use of a hand-held sextant that utilizes star sighting in microgravity. 

Read more about how we’re testing this tool in space!  

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5 Reasons our Space Launch System is the Backbone for Deep Space Exploration

Our Space Launch System (SLS) will be the world’s most powerful rocket, engineered to carry astronauts and cargo farther and faster than any rocket ever built. Here are five reasons it is the backbone of bold, deep space exploration missions.

5. We’re Building This Rocket to Take Humans to the Moon and Beyond

The SLS rocket is a national asset for leading new missions to deep space. More than 1,000 large and small companies in 44 states are building the rocket that will take humans to the Moon. Work on SLS has an economic impact of $5.7 billion and generates 32,000 jobs. Small businesses across the U.S. supply 40 percent of the raw materials for the rocket. An investment in SLS is an investment in human spaceflight and in American industry and will lead to applications beyond NASA.

4. This Rocket is Built for Humans

Modern deep space systems are designed and built to keep humans safe from launch to landing.  SLS provides the power to safely send the Orion spacecraft and astronauts to the Moon. Orion, powered by the European Service Module, keeps the crew safe during the mission. Exploration Ground Systems at NASA’s Kennedy Space Center in Florida, safely launches the SLS with Orion on top and recovers the astronauts and Orion after splashdown.

3. This Rocket is Engineered for a Variety of Exploration Missions

SLS is engineered for decades of human space exploration to come. SLS is not just one rocket but a transportation system that evolves to meet the needs of a variety of missions. The rocket can send more than 26 metric tons (57,000 pounds) to the Moon and can evolve to send up to 45 metric tons (99,000 pounds) to the Moon. NASA has the expertise to meet the challenges of designing and building a new, complex rocket that evolves over time while developing our nation’s capability to extend human existence into deep space.

2. This Rocket can Carry Crews and Cargos Farther, Faster

SLS’s versatile design enables it to carry astronauts their supplies as well as cargo for resupply and send science missions far in the solar system. With its power and unprecedented ability to transport heavy and large volume science payloads in a single mission, SLS can send cargos to Mars or probes even farther out in the solar system, such as to Jupiter’s moon Europa, faster than any other rocket flying today. The rocket’s large cargo volume makes it possible to design planetary probes, telescopes and other scientific instruments with fewer complex mechanical parts.

1. This Rocket Complements International and Commercial Partners

The Space Launch System is the right rocket to enable exploration on and around the Moon and even longer missions away from home. SLS makes it possible for astronauts to bring along supplies and equipment needed to explore, such as pieces of the Gateway, which will be the cornerstone of sustainable lunar exploration. SLS’s ability to launch both people and payloads to deep space in a single mission makes space travel safer and more efficient. With no buildings, hardware or grocery stores on the Moon or Mars, there are plenty of opportunities for support by other rockets. SLS and contributions by international and commercial partners will make it possible to return to the Moon and create a springboard for exploration of other areas in the solar system where we can discover and expand knowledge for the benefit of humanity.

Learn more about the Space Launch System.

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Remember the Women Who Made #Apollo50th Possible

As the world celebrates the 50th anniversary of the historic Moon landing, we remember some of the women whose hard work and ingenuity made it possible. The women featured here represent just a small fraction of the enormous contributions made by women during the Apollo era. 

Margaret Hamilton, Computer Programmer

Margaret Hamilton led the team that developed the building blocks of software engineering — a term that she coined herself. Her systems approach to the Apollo software development and insistence on rigorous testing was critical to the success of Apollo. In fact, the Apollo guidance software was so robust that no software bugs were found on any crewed Apollo missions, and it was adapted for use in Skylab, the Space Shuttle and the first digital fly-by-wire systems in aircraft.

In this photo, Hamilton stands next to a stack of Apollo Guidance Computer source code. As she noted, “There was no second chance. We all knew that.”

Katherine Johnson, Aerospace Technologist

As a very young girl, Katherine Johnson loved to count things. She counted everything, from the number of steps she took to get to the road to the number of forks and plates she washed when doing the dishes.

As an adult, Johnson became a “human computer” for the National Advisory Committee for Aeronautics, which in 1958, became NASA. Her calculations were crucial to syncing Apollo’s Lunar Lander with the Moon-orbiting Command and Service Module. “I went to work every day for 33 years happy. Never did I get up and say I don't want to go to work."

Judy Sullivan, Biomedical Engineer

This fabulous flip belongs to biomedical engineer Judy Sullivan, who monitored the vital signs of the Apollo 11 astronauts throughout their spaceflight training via small sensors attached to their bodies. On July 16, 1969, she was the only woman in the suit lab as the team helped Neil Armstrong suit up for launch.

Sullivan appeared on the game show “To Tell the Truth,” in which a celebrity panel had to guess which of the female contestants was a biomedical engineer. Her choice to wear a short, ruffled skirt stumped everyone and won her a $500 prize. In this photo, Sullivan monitors a console during a training exercise for the first lunar landing mission.

Billie Robertson, Mathematician

Billie Robertson, pictured here in 1972 running a real-time go-no-go simulation for the Apollo 17 mission, originally intended to become a math teacher. Instead, she worked with the Army Ballistic Missile Agency, which later became rolled into NASA. She created the manual for running computer models that were used to simulate launches for the Apollo, Skylab and Apollo Soyuz Test Project programs. 

Robertson regularly visited local schools over the course of her career, empowering young women to pursue careers in STEM and aerospace.

Mary Jackson, Aeronautical Engineer

In 1958, Mary Jackson became NASA’s first African-American female engineer. Her engineering specialty was the extremely complex field of boundary layer effects on aerospace vehicles at supersonic speeds.

In the 1970s, Jackson helped the students at Hampton’s King Street Community center build their own wind tunnel and use it to conduct experiments. “We have to do something like this to get them interested in science," she said for the local newspaper. "Sometimes they are not aware of the number of black scientists, and don't even know of the career opportunities until it is too late."

Ethel Heinecke Bauer, Aerospace Engineer

After watching the launch of Sputnik in October 1957, Ethel Heinecke Bauer changed her major to mathematics. Over her 32 years at NASA, she worked at two different centers in mathematics, aerospace engineering, development and more. 

Bauer planned the lunar trajectories for the Apollo program including the ‘free return’ trajectory which allowed for a safe return in the event of a systems failure  — a trajectory used on Apollo 13, as well as the first three Apollo flights to the Moon. In the above photo, Bauer works on trajectories with the help of an orbital model.

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I've been very curious about the basis on which the landing site is decided! I read that it will land in the Jerezo crater, so is there a particular reason behind choosing that place for the landing?

Solar System: 10 Things to Know This Week...Halloween Edition!

This week, we're getting into the Halloween spirit with 10 spooktacular things to let your imagination run wild. 

It's not Halloween without our favorite scary characters, but what if they could stop bothering us Earthlings and go far, far away? We begin with where Dracula, Frankenstein, and other creepy creatures might choose to live if the galaxy were theirs to claim...

1. The dark (k)night.

The prince of darkness himself, Dracula, can finally seek sweet respite from the Sun. We think he'd love to live on a rocky planet named YZ Ceti d that orbits so close to its red star that it's tidally locked keeping one side of the planet in perpetual nighttime and the other side in perpetual daytime, with a brilliant red sky (though we can guess which side Dracula will prefer). 

2. Where art thou, werewolves? 

Home sweet home for our furry Full Moon friends might just be on Trappist-1, a planetary system with seven planets—and where standing on one planet would mean the other planets look like six moons (some as big as our Moon in the sky). 

3. Left in the dust. 

We couldn't think of anyone better to live on Proxima b than The Mummy. Hopefully this ancient monster can finally rest in peace on an exoplanet that scientists theorize is a desert planet once home to ancient oceans. 

4. Cloudy with a chance of Frankenstein.

One scientific experiment we'd like to conduct: whether Frankenstein would rather live on HAT-P-11b or Kepler-3b, theorized to have fierce thunderstorms and lightning. 

5. The walking dead. 

We're pretty confident that if zombies were to pick a planet, they'd want one that shares their love of death and destruction. We think they'd feel right at home on one of the pulsar planets, which are scorched by radiation because they orbit a dead star. 

6. Rest your weary bones. 

Skeletons need look no further: Osiris, an exoplanet that's so close to a star that it's "losing its flesh" as the star destroys it, seems like a perfect match. 

7. Enough of the scary stuff. 

For kids out there, turn pumpkin decorating into an out-of-this-world activity with space-themed stencils, from Saturn to the Sun. 

8. Spooky sounds. 

Cassini's radio emissions from Saturn could give creaky doors and howling winds a run for their money. Listen to the eerie audio recordings here and find more HERE.

9. Pumpkin-carve like a NASA engineer. 

NASA engineers design and build robots that can fly millions of miles to study other planets for a living—so on Halloween, they can't help but bring that creative thinking to the grand old tradition of pumpkin carving. Take a cue from their creations with these insider tips.

10. Detective for a day. 

From blades of ice on Pluto to a fuzzy, white "bunny" photographed on Mars, become a solar system sleuth and see if you can solve the stellar mysteries in this slideshow (then compare with how scientists cracked the case). 

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10 Questions for Our Chief Scientist

NASA Chief Scientist…pretty cool title, right? The office represents all the scientific endeavors at NASA, ensuring they’re aligned with and fulfilling the administration’s science goals.  

After more than three years as Chief Scientist, Ellen Stofan is departing for new adventures. We caught up with her to ask 10 questions about her role and what she will miss most after she leaves the agency. Take a look…

1) What were some of your expectations coming in as NASA’s chief scientist?

When I started as Chief Scientist, all I knew is that I would be science advisor to the Administrator, Charlie Bolden, overseeing the agency’s science portfolio. What I did not realize at the time was the degree that I would be impressed by him. 

Charlie is an amazing leader who deeply cares about each and every person at this agency. He makes everyone feel valued. That is why NASA has just been voted by our employees for the fifth straight year as the Best Place to Work in the federal government!

2) What do you think it the next big thing for NASA science?

Looking across our science portfolio, I think the most exciting area, which actually connects everything we do, is the search for life beyond Earth. People have long wondered if we are alone, and we are now actually going to answer that question in the next few decades. We are exploring Mars, where it is very likely that life evolved at around the same time life evolved here on Earth. Conditions on Mars deteriorated after about a billion years, so life either went underground, or became extinct. It will likely take future Mars astronauts to find the best evidence of Mars life.

We also are planning to explore the ocean worlds of the outer solar system, like Europa, where we might find life in subsurface oceans. Beyond our solar system, the thousands of planets discovered by the Kepler Space Telescope have made me very optimistic that we are close to finding an Earth 2.0—though that will take us a little longer.

3) NASA science rewrites textbooks all the time. What is something you've seen here that has the potential to occur in the future that will change the textbooks for kids of tomorrow?

For kids 16 and under today, for every day of their life, we have been living and working in space on board the International Space Station. Now we are ready to take that next step in the coming decade, to move humans beyond low-Earth orbit where we have been for such a long time, out to the vicinity of the moon and then on to Mars. 

These kids are the “Mars generation,” and the exploration of Mars will change our outlook in profound ways, from looking back at Earth -- that will just look like another star -- to finding evidence of life beyond Earth. So it will not just change science textbooks, it will change how we look at ourselves when we become a multi-planetary species.

4) Behind every pretty space image is a team of scientists who analyze all the data to make the discovery happen. What do you wish the public knew about the people and work that goes into each of those pretty pictures?

It really does take a team.  When I go out and talk to school kids, I tell them learning how to be a good member of a team is so important in life. You need to learn to be a leader and a follower, and above all a listener. Our teams at NASA are becoming more and more diverse, which is incredibly important. If everyone looks the same and comes from the same background, they are likely to approach problems the same way. And when you are trying to do tough things -- from addressing climate change to sending humans to Mars -- you need the best team, which means a diverse team.

5) We have a lot of opportunities for citizen science. What’s one opportunity you wish everyone knew about that they could get involved with at NASA?

Go to www.nasa.gov/solve where you can find all kinds of great opportunities to join us at NASA in searching for planets around other stars, exploring Mars, helping us gather data about this planet, and tackling technology challenges. We really are stronger together, and getting the public involved in what we do is helping us get more good science every day. Even more importantly, it lets people know that science is fun!

6) What changes did you make at the agency while you were there?

As Chief Scientist, I got to work on a lot of fun challenges, from our strategy on how to get humans to Mars, to learning about and promoting the research we do every day on the International Space Station. But one of the things that I am most proud of is that, working with my team, NASA now collects voluntary demographic data on all of our grant proposals. Implicit or unconscious bias is all around us; we may act on deep-seated biases that we don’t even know we have. The first step in dealing with bias is seeing if you have a problem, and that is what the data collection will tell us.

7) You worked a lot with kids as the agency’s Chief Scientist. How important do you feel STEM education is for NASA?

We need the next generation of scientists, doctors, computer programmers, technologists and engineers, and NASA provides the inspiration and hands-on activities that help get kids interested in science. Because of climate change, we are facing rising sea levels, changing patterns of agriculture, and changing weather. We need good engineers and scientists to help us mitigate the effects of climate change and reduce carbon emissions.

On top of that, we live in a society that is dependent on technology; I don’t think most of us can go very long without checking our smartphones. But as technology becomes more complex, we need everyone in society to have at least a basic understanding of it, and that’s where the importance of STEM education comes in. We are ALL consumers of science and technology. We all need to be informed consumers.

8) What solar system destination are you still most excited/eager for NASA to still go explore?

As a planetary geologist, I am most excited by one of the ocean worlds of the outer solar system. Titan, one of Saturn’s moons, is an amazing little world where it rains, and the liquid forms rivers, lakes and seas. But this liquid is actually liquid methane and ethane --basically gasoline, rather than water -- due to the extremely cold temperatures out by Saturn. 

Titan is an excellent place to explore to help us better understand how oceans and atmospheres interact, and maybe even understand more about the limits of life. We think water is critical to the evolution of life, but Titan may tell us that having a liquid is the most important factor.

9) What will you miss most?

It’s the people of NASA whom I will miss the most. Everyone I work with is so committed to the mission of this agency—pushing back the frontiers of science and technology to accomplish great things for the nation. NASA represents the best of this country. We demonstrate that with hard work and determination, we can explore the universe, our galaxy, our solar system and our home planet. 

Our partnerships with other space agencies from around the world and with the private sector here have shown me that great teams accomplish great things. I like to say that NASA is the keeper of the future—we don’t just wait for the future to happen. We work to create it every day.

10) In your opinion, after seeing everything you've seen here, why should people care about the science at NASA?

At NASA, we gather the data to help answer the most fundamental and profound questions: Where did we come from? How does our planet and our universe work? What is the fate of our planet? It is only by exploring, by making measurements, by answering scientific questions that we can move forward as a society. And in doing so, we push technology and engineering in ways that benefit us every day right here on Earth. 

NASA makes measurements that show how the sea level is rising, how Arctic ice is melting, and how weather patterns are changing. We also gather data to help farmers grow more crops using less water, help understand our water resources, and do the research to improve forecasting. These data keep us secure and improve the quality of life on Earth every day.

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21 Years of Amazing Earth Imagery

On April 29, 1999, NASA Earth Observatory started delivering science stories and imagery to the public through the Internet. Today, we turn 21! So much has changed in the past two decades... 

One of the most notable changes is the way we view our home planet. Check out some of the beautiful imagery of our planet over the past 21 years.

2000: Pine Island Glacier

Most people will never see Pine Island Glacier in person. Located near the base of the Antarctic Peninsula—the “thumb” of the continent—the glacier lies more than 2,600 kilometers (1,600 miles) from the tip of South America. That’s shorter than a cross-country flight from New York to Los Angeles, but there are no runways on the glacier and no infrastructure. Only a handful of scientists have ever set foot on its ice.

This animation shows a wide view of Pine Island Glacier and the long-term retreat of its ice front. Images were acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) on our Terra satellite from 2000 to 2019. Notice that there are times when the front appears to stay in the same place or even advance, though the overall trend is toward retreat. Read more.

2002: The Blue Marble

In February 2002, Earth Observatory published this “blue marble” image based on the most detailed collection of true-color imagery of the entire Earth at that time. Using a collection of satellite-based observations, scientists and visualizers stitched together months of observations of the land surface, oceans, sea ice and clouds into a seamless, true-color mosaic of every square kilometer (.386 square mile) of our planet. Most of the information contained in this image came from Moderate Resolution Imaging Spectrometer (MODIS), illustrating the instrument's outstanding capacity to act as an integrated tool for observing a variety of terrestrial, oceanic and atmospheric features of the Earth. Read more.

2009: Tsauchab River Bed

The Tsauchab River is a famous landmark for the people of Namibia and tourists. Yet few people have ever seen the river flowing with water. In December 2009, an astronaut on the International Space Station caught this glimpse of the Tsauchab River bed jutting into the sea of red dunes. It ends in a series of light-colored, silty mud holes on the dry lake floor.

Like several other rivers around the Namib Desert, the Tsauchab brings sediment down from the hinterland toward the coastal lowland. This sediment is then blown from the river beds, and over tens of millions of years it has accumulated as the red dunes of the Namib Sand Sea. Read more. 

2012: Manning Island and Foxe Basin, Canada

Although it may look like a microscope’s view of a thin slice of mineral-speckled rock, this image was actually acquired in space by the Earth Observing-1 satellite in July 2012. It shows a small set of islands and a rich mixture of ice in Foxe Basin, the shallow northern reaches of Hudson Bay.

The small and diverse sizes of the ice floes indicate that they were melting. The darkest colors in the image are open water. Snow-free ice appears gray, while snow-covered ice appears white. The small, dark features on many of the floes are likely melt ponds. Read more.

2013: A Lava Lamp Look at the Atlantic

Stretching from tropical Florida to the doorstep of Europe, this river of water carries a lot of heat, salt, and history. The Gulf Stream is an important part of the global ocean conveyor belt that moves water and heat across the North Atlantic from the equator toward the poles. It is one of the strongest currents on Earth, and one of the most studied.

This image shows a small portion of the Gulf Stream as it appears in infrared imagery. Data for this image was acquired on April 9, 2013, by the Thermal Infrared Sensor (TIRS) on the Landsat 8 satellite. TIRS observes in wavelengths of 10.9 micrometers and 12.0 micrometers. The image above is centered at 33.06° North latitude, 73.86° West longitude, about 500 kilometers (300 miles) east of Charleston, South Carolina. Read more.

2016: Curious Ensemble of Wonderful Features

When John Wesley Powell explored the Colorado River in 1869, he made the first thorough survey of one of the last blank spots on the map. The expedition began in May at Green River, Wyoming, and ended three months later at the confluence of the Colorado and Virgin Rivers in present-day Nevada.

About two months into their journey, the nine men of the expedition found themselves in Glen Canyon. As the men traveled along the serpentine river channel, they encountered what Powell later described in Canyons of Colorado as a “curious ensemble of wonderful features.”

From above, the view of Glen Canyon is equally arresting. In 2016, an astronaut aboard the International Space Station took several photographs that were combined to make a long mosaic. The water has an unnatural shade of blue because of sunglint, an optical phenomenon that occurs when sunlight reflects off the surface of water at the same angle that a camera views it. Click here to see the long mosaic.

2019: Lena Delta Shakes Off Water

For most of the year, the Lena River Delta—a vast wetland fanning out from northeast Siberia into the Arctic Ocean—is either frozen over and barren or thawed out and lush. Only briefly will you see it like this.

After seven months encased in snow and ice, the delta emerges for the short Arctic summer. The transition happens fast. The animation above, composed of images from the Moderate Resolution Imaging Spectroradiometer (MODIS) on our Aqua satellite, shows the transformation from June 3-10, 2019. Read more.

2020: Making Waves in the Andaman Sea

When tides, currents and gravity move water masses over seafloor features, they can create wave actions within the ocean. Oceanographers began studying these internal waves from ships in the 1960s, and the modern era of satellites has made it possible to see them on a grand scale. The Operational Land Imager (OLI) on Landsat 8 captured these images of the Andaman Sea on November 29, 2019. The reflection of the Sun on the ocean—sunglint—helps make the internal waves visible.

Internal waves form because the ocean is layered. Deep water tends to be colder, denser and saltier, while shallower water is often warmer, lighter and fresher. The differences in density and salinity cause layers of the ocean to behave like different fluids. When tides, currents, gravity and Earth’s rotation move these different water masses over seafloor formations (such as ridges or canyons), they create waves within the sea. Read more.

These images were taken from NASA Earth Observatory! 

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