vania-janet/multiturn-rag-retrieval-data huggingface dataset:
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Montgomery Reef Revealed
Large tidal swings expose a plateau-shaped reef around Australia’s Yawajaba island at low tide.
 
Published May 18, 2024

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Shasta Lake Fills Up Again
For the second year in a row, California’s largest reservoir filled to nearly 100 percent capacity.
Published May 17, 2024

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Blue Marble Next Generation
12 months of high-resolution global true color satellite imagery.
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Ocean temperatures can influence weather, such as hurricane formation, and climate patterns, such as El Niño. These maps show the temperature at the surface of the world’s seas and oceans.

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How to Interpret a Satellite Image: Five Tips and Strategies
What do you do when presented with a new satellite image? Here's what the Earth Observatory team does to understand the view.
Published Nov 18, 2013

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Greenness is an important indicator of health for forests, grasslands, and farms. The greenness of a landscape, or vegetation index, depends on the number and type of plants, how leafy they are, and how healthy they are.

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Citizen Scientists Capture Brilliant Photos of the Aurora
Participants in NASA's Aurorasaurus project captured these images during the May 2024 geomagnetic storm. 
Published May 15, 2024

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Colorful Celtic Sea
Satellites captured an expansive blue and green phytoplankton bloom in the waters off France.
Published May 14, 2024

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Smoke and Fire in British Columbia
Unusually early and intense fires are spreading rapidly amid drought and high winds.
Published May 13, 2024

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Sundown and Lights Up Over the U.S. Northeast
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Winter is Coming
This part of Khabarovsk territory often sees average highs in the -30s °C (-20s °F) by December, a month when the area receives just 6 hours of daylight. In October, 10 hours of daylight is the average.
With the Sun low on the horizon, long shadows had spread across the lower slopes of the mountains when the Operational Land Imager (OLI) on Landsat 8 acquired the image. Notice the blue areas, where shadows fall on areas where snow has fallen. With less direct sunlight hitting these patches (and washing out other colors), more blue light from the sky was reflected by the snow.
NASA Earth Observatory image by Joshua Stevens, using Landsat data from the U.S. Geological Survey. Story by Adam Voiland.

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Long blue shadows on the snow portend frigid days ahead in this far eastern corner of Siberia.
Image of the Day for October 21, 2020

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Landsat 8 — OLI

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Oct 20, 2020

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References & Resources

Baird, Christopher (2014, February 10) Why doesn't the outside world appear blue even though so much light comes from the blue sky? Accessed October 20, 2020.
Krestov, P. (2003) Forest Vegetation of Easternmost Russia (Russian Far East). Geobotany, 28.
Russian Nature Biomes and Regions of Northern Eurasia. Accessed October 20, 2020.
UCAR (2020) Is Snow White? Maybe, or Maybe Not. Accessed October 20, 2020.

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Russia’s Golden Autumn
Primorsky Krai, in the Russian Far East, displays some of the planet’s most striking fall color.

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Blizzard in southern Chile

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A Blaze of Yellow
In northern Sweden, bursts of fall color fill valleys before the darkness of winter descends.

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Watching for Color in the Wasatch Back
The water caused leaves to change color later than usual this year, but the color was likely more vibrant, according to news reports.
NASA Earth Observatory images by Wanmei Liang, using Landsat data from the U.S. Geological Survey. Story by Kathryn Hansen.

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The eastern side of the Wasatch Range in autumn displays abundant reds and oranges, followed by vibrant yellows.
Image of the Day for November 13, 2023

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Landsat 8 — OLI
Landsat 9 — OLI-2

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Nov 12, 2023

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References & Resources

The Daily Universe (2023, September 29) Fall colors in Utah set to peak in October. Accessed November 9, 2023.
KPCW (2023, September 26) Vibrant fall colors explode in Wasatch Back thanks to water supply. Accessed November 9, 2023.
ParkRecord (2023, September 23) Autumn returns in red, orange and yellow. Accessed November 9, 2023.
Utah.com Alpine Loop Scenic Drive. Accessed November 9, 2023.
Utah.com Utah’s Wasatch Back Region. Accessed November 9, 2023.
Utah State University Fall Color in Utah. Accessed November 9, 2023.

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Coastal Color in New Zealand
Patchworks and swirls of color adorn the eastern coast of the South Island.

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Fall Color Arrives in the U.S. and Canada
Leaves change from green to orange and brown across the United States and Canada.

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Activity at Kizimen Volcano
Clouds obscured Kizimen Volcano’s plume in this true-color satellite image, but in false-color the plume shows up clearly.

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Phytoplankton off South African Coast
EO Kids
Picturing Earth From the Space Station

Find out what it takes to be a space photographer on the International Space Station (ISS), play a data detective game and build your landform recognition skills like an astronaut.

Smoky Skies and Satellites

Explore how wildfire smoke travels in our sky and find out how NASA satellites track it in "Smoky Skies and Satellites." Plus, create your own data visualization.

Keeping a Close Eye on the Storm: Hurricanes

Learn all about how satellites track storms – from formation, landfall, and the aftermath

Barrier Islands: Sands & Lands in Motion

Explore the shore with EO Kids' Barrier Islands: Sands & Lands in Motion. Learn about Earth’s changing shorelines, especially barrier islands.

Shifting Shapes of Sandy Scapes

Building sand castles is a summer pastime, whether in a sandbox or at the beach. Nature builds with sand, too, using wind to create different shapes.

The Ozone Hole: We Need More Sunscreen

EO Kids is discovering more about Earth’s ozone layer and about what happens when it gets damaged. Plus, create your own ozone hole map in our “Data Viz” activity: “Mapping Ozone.”

Making and Melting Ice at Earth’s Poles

Find out about sea ice and its effects on ecosystems and global climate by looking at how and when it forms on Earth. Plus, learn how different types of water freeze in our “DIY Science” activity: “Saltwater is Cool (Literally).”

Peeking at Penguins: Poop from Space

Did you know that satellites can be used to find penguin populations by looking at what they leave behind? EO Kids is discovering more about penguins by looking at their poop from space.

Night Vision: Learning from City Lights

All those sparkly lights reveal a lot about where and how people live on Earth – everything from population, to disaster recovery, to where people are celebrating.

The Shape of Farming: Water For Crops

Farmers use a number of different methods
to irrigate crops, and some of them result in
pretty interesting shapes.

Cleaning Up Our Air

Take a breath of fresh air. Learn how the air we breathe has become cleaner in the latest issue of EO Kids, Cleaning Up Our Air
What Causes the Seasons? | NASA Space Place – NASA Science for Kids
For those of us who live in the Northern Hemisphere where it's summer in July and winter in January, that seems backwards, doesn't it? That just goes to prove that Earth's distance from the Sun is not the cause of the seasons.

Related Resources for Educators

Seasons (Educator Guide to go with Seasons Spotlite video)
Seasons (Nearpod Lesson to go with Seasons Spotlite video)
Our World: Sun's Position 
Sun's Position (Educator Guide to go with Sun's Position Spotlite video)
Sun's Position (Nearpod Lesson to go with Sun's Position Spotlite video)

 	article last updated July 22, 2021
 

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In Depth - NASA Science
Stars are affected by the gravitational tug of their orbiting planets and, when observed through a telescope, this affects the star's light spectrum. If the star moves in the direction of the observer it will appear to be shifted toward blue. If it is moving away from the observer, it will shift toward the red. Observing this is known as the radial velocity method.NASA’s Exoplanet Space TelescopesThousands of exoplanets have been discovered and confirmed orbiting other stars. The first evidence of exoplanets dates to 1917 when Van Maanen identified the first polluted white dwarf, however, the first confirmed detection of an exoplanet would not come until the 1990s. The discovery of exoplanets grew exponentially in the years to follow with the launch of the Kepler Space Telescope.The Kepler mission was specifically designed to survey our region of the Milky Way galaxy to discover hundreds of Earth-size and smaller planets in or near the habitable zone (also called the “Godilocks zone,” the area around a star where rocky planets could have liquid water on the surface) and determine the fraction of stars that might have such planets around them. After the second of Kepler’s four gyroscope-like wheels failed in 2013, Kepler completed its prime mission that November and began its extended mission, K2. The spacecraft was retired in 2018, but Kepler data are still being used to find exoplanets (more than 2,700 confirmed so far).NASA’s Spitzer Space Telescope (2013-2020) was not designed to search for exoplanets, but its infrared instruments made it an excellent exoplanet explorer. It was used in the notable discovery of the TRAPPIST-1 system. In 2018 the Transiting Exoplanet Survey Satellite (TESS) was launched as a successor to Kepler to discover exoplanets in orbit around the brightest dwarf stars, the most common star type in our galaxy. NASA’s James Webb Space Telescope and the future Nancy Grace Roman Space Telescope hold great promise for what we can learn from exoplanets. Through spectroscopy, reading light signatures for information, astronomers hope to learn more about planet atmospheres and the conditions of the planets themselves.The Milky Way, our own galaxy, stretches across the sky above the La Silla Observatory in Chile.
Glossary | NASA Space Place – NASA Science for Kids
We have one view of stars here on Earth, but from another solar system or galaxy, the constellations would look different. 
Corona: The outer atmosphere of a star. 
Cosmos: The universe seen as an orderly, harmonious whole. 

Crater: A large, bowl-shaped dent in the ground. They can be caused by an explosion or the impact of a meteorite. 
Dwarf planet: Objects that are round and orbit the sun, just like planets do. But unlike planets, dwarf planets are not able to clear their path around the sun. That means there are other objects orbiting at roughly the same distance from the sun. A dwarf planet is much smaller than a planet (smaller even than Earth's moon), but it is not a moon. Pluto is the best known of the dwarf planets.

El Niño: A weather condition that sometimes occurs in the Pacific Ocean. It is so big that it affects weather all over the world. It starts with unusually warm water in the Pacific Ocean near the equator.

Electromagnetic Spectrum: The name for all the different kinds of light and energy in the universe. This includes radio waves, microwaves, infrared radiation, visible light, ultraviolet light, X-rays, and gamma rays. 
Equator: The circle around a planet or moon that is the same distance from its north pole and its south pole.

Exoplanet: A planet that freely floats between stars or one that orbits a star outside our solar system.

Galaxy: A collection of thousands to billions of stars held together by gravity. The galaxy we live in is called the Milky Way.

Gamma rays: Part of the electromagnetic spectrum, also called gamma radiation. These waves have lots of energy. They come from big events like solar flares and exploding stars.
Gas: A loose collection of atoms moving around each other.

GPS: This stands for Global Positioning System. It’s a system that uses satellites, ground stations, and receivers to tell you exactly where you are on Earth.
Gravity: A force that pulls matter together.
Greenhouse gas: Gases in the atmosphere that trap heat from the sun. Some greenhouse gases are carbon dioxide, methane, water vapor, and nitrous oxide.
Faint Glow, Clear Signal from Plants
The maps above show how the solar induced fluorescence signal evolved across the Midwest during a typical growing season (2018) and during the record precipitation and flood conditions of 2019. The third column shows the difference between the two years. Notice that fluorescence in 2018 peaked strongly in July and then declined, which is the typical progression of productivity across Midwest croplands.
The 2019 maps tell a different story. By the end of April 2019, the U.S. had experienced its wettest 12-month period on record. The Midwest was hit particularly hard, with saturated soils and widespread flooding across the Mississippi and Missouri river watersheds. The conditions caused farmers to delay planting by a few weeks in most states and up to five weeks in Illinois. As a result, fluorescence that year was weaker than usual in June and July, when croplands were much less productive. August and September showed higher-than-usual fluorescence, indicating an extended growing season. But the 2019 season as a whole was still not productive as 2018.

2019PNG

“Extreme climate events such as flood, drought, and heatwave are expected to increase with global warming, and have a direct impact on crop productivity and food security,” said Yin, a researcher at Caltech and author of the NASA-funded study. For instance, the agricultural productivity of the U.S. Midwest is being threatened by climate change, as variations in snow and rainfall over the past three decades have reduced farmers’ flexibility in timing their springtime planting.
Cropland productivity also has implications beyond food security; it also influences the amount of carbon dioxide stored in the atmosphere and the land. Around the planet, carbon is constantly exchanged between the land, atmosphere, and oceans as part of the carbon cycle. Plants, trees, and grasses—including farmlands—are an important part of the cycle, converting carbon dioxide into food during photosynthesis. When crops exhibit lower fluorescence values, less photosynthesis is occurring. In turn, those crops are taking up less carbon dioxide.
Based on the TROPOMI SIF data, the researchers estimated that the carbon uptake by Midwest crops in June and July 2019 was reduced by 100 million metric tons compared to the previous year due to the floods and late planting.
Applications | Terra
See Air Quality on the Applied Remote Sensing Education & Training web site.

Volcanic Eruptions
The Federal Aviation Administration (FAA) uses ASTER, MISR, and MODIS for volcanic ash monitoring. Awareness of volcanic eruptions help FAA direct air traffic away from dangerous hot spots.

Fires
The U.S. Forest Service, Department of Agriculture, EPA and other international fire monitoring community use ASTER, MISR, and MODIS for forest fire monitoring.  Near real-time data from the MODIS Rapid Response System are used by federal and regional stakeholders to assess and monitor forest fires.

 Weather Forecast
The National Environmental Satellite, Data, and Information Service use CERES, MISR, and MODIS for weather forecast, which are used by national and international weather agencies to disseminate weather information. Real-time MODIS data such as sea surface temperature and total precipitable water vapor are used by the National Weather Service stations across the United States.

Agriculture
The U.S. Department of Agriculture and Foreign Agriculture Service use CERES, MODIS, and MOPITT for carbon management and crop assessment. The consequences of climate variablity on agriculture is essential in human survival.

Recent large scale natural and man-made disasters where Terra instruments were used for applied and operational uses include:
Oil Spills
In April 2010, off the Gulf of Mexico, a commercially operated oil rig exploded.  This resulted in one of the worse oil spills in the history of the petroleum industry; the event is known as the Deepwater Horizon Oil Spill.  For the duration of the oil spill, Terra instruments (ASTER, MISR, and MODIS) were active in monitoring the spill.  ASTER produced over 200 high-resolution images to help determine the impact to surrounding wetlands; it also showed thermal images of man-made fires.  MISR produced multi-angle view of the oil spill that showed the difference between the oil spill and false sun glint areas.  MODIS provided an image every two days and a bird’s eye view of the oil spill.
Volcanic Eruptions
In April and May 2010, the Eyjafjallajökull volcano in Iceland erupted that caused major distress to the environment and air traffic.
Sun-Earth Days 2013: Articles
Increased exposure to high energy cosmic rays can result in health problems including cancer. Flights over the poles increase this radiation risk. This is why some airlines prohibit pregnant airline attendants from flying.
Power Grids
Remembering that moving magnetic fields generate current, geomagnetic storms around the Earth from CMEs can jar the magnetosphere enough to produce "Geomagnetically Induced Currents" or GICs in electrical power grids. The added current can cause transformers to overload and create large scale power outages. The economic cost of such an outage can be in the $10's of millions. Such an event blacked out much of Quebec in 1989 for over 9 hours.

Figure 18: Degradation in SOHO spacecraft solar cell efficiency over time

Satellite Operations
The sensitive electronics in satellites and spacecraft are particularly vulnerable to the effects of increased solar activity. Particle radiation can compromise IC circuit boards, flipping bits in memory chips from Single Event Upsets (SEUs) and damaging micro circuit junctions. Solar cells are degraded by long term exposure to energetic solar particles / solar proton events as well as cosmic rays. The defense against this is to radiation harden the electronics, reducing their susceptibility to ionizing EM and particle radiation.
Weather And Climate Connection?
 The sun's output is remarkably constant over periods of thousands of years. The "Solar Constant" which is a measure of flux density or the average amount EM radiation at all wavelengths per unit area received by the Earth at its upper atmosphere is measured my Earth orbiting satellites (since 1978) to be 1,361 (kW/m2) and is now known to vary by only 0.1% over a solar cycle which is equal to about 2 watts per square meter, not enough to strongly influence climate. Though small, the solar constant does vary periodically with the 11 year sunspot cycle as well as solar cycles of 88 (Gleisberg Cycle), 208 (DeVries Cycle), and 1,000 years (Eddy Cycle). On much longer time scales, the sun has increased its luminosity by about 30% over its 4.6 billion year life time due to lessoning outward-directed pressure and thus contraction and heating of the core through its thermonuclear fusion process.
Athens at Night
Athens at Night

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Athens at Night

September 17, 2022JPEG

An astronaut aboard the International Space Station took this nighttime photograph of Athens, the capital city of Greece. The city lies on the complex coastline of the Attica Peninsula in Southern Greece. Streets meander through the city like illuminated rivers, and the urban sprawl extends to the coast.
In nighttime photos taken from above, sharp transitions from lit to unlit areas often occur where urban development meets a waterbody or rough, undeveloped terrain. In this photo, illumination cuts off sharply at the southern edge of Athens, where the city meets the Saronic Gulf. The city’s northwestern reaches also display a sharp drop in illumination due to the Párnitha mountains. Likewise, the lack of light between the city and Athens International Airport is due to the rugged terrain of the Hymettus mountains. The range is blanketed with forests that host archaeological sites and recreational areas.
Ancient and modern elements in Athens are also contrasted at night. Yellow and orange-hued lights indicate older, high-pressure sodium lighting. Bright white-toned lighting indicates areas illuminated with more recent LED (light-emitting diode) technology.