vania-janet/multiturn-rag-retrieval-data huggingface dataset:
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Imagine the Universe! Dictionary
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(Note - Greek letters are written out by name - alpha, beta etc.)
A
absorption
The process in which light or other electromagnetic radiation gives up its energy to an atom or molecule.
absorption line spectrum
A spectrum showing dark lines at some narrow color regions (wavelengths). The lines are formed by atoms absorbing light, which lifts their electrons to higher orbits.
accretion
Accumulation of dust and gas onto larger bodies such as stars, planets and moons.
accretion disk
A relatively flat sheet of gas and dust surrounding a newborn star, a black hole, or any massive object growing in size by attracting material.
active galactic nuclei (AGN)
A class of galaxies which spew massive amounts of energy from their centers, far more than ordinary galaxies. Many astronomers believe supermassive black holes may lie at the center of these galaxies and power their explosive energy output.

 Tell me about AGN!
 Tell me more about AGN!

angstrom
A unit of length equal to 0.00000001 centimeters. This may also be written as 1 x 10-8 cm (see scientific notation).
angular momentum
Imagine the Universe!
In addition, nothing can prevent a particle from hitting the singularity in a very short amount of proper time once it has entered the horizon. In this sense, the event horizon is a "point of no return". See Schwarzschild radius.
evolved star
A star near the end of its lifetime when most of its fuel has been used up. This period of the star's life is characterized by loss of mass from its surface in the form of a stellar wind.
EXOSAT
European Space Agency's X-ray Observatory

 Tell me more about EXOSAT.

extragalactic
Outside of, or beyond, our own galaxy.
F
Fast Fourier Transformation (FFT)
A Fourier Transform is the mathematical operation that takes measurements made with a radio interferometer and transforms them into an image of the radio sky. The Fast Fourier Transform is technique used by computer programs that allows the Fourier Transform to be computed very quickly.
Fermi acceleration
In order to explain the origins of cosmic rays, Enrico Fermi (1949) introduced a mechanism of particle acceleration, whereby charged particles bounce off moving interstellar magnetic fields and either gain or lose energy, depending on whether the "magnetic mirror" is approaching or receding. In a typical environment, he argued, the probability of a head-on collision is greater than a head-tail collision, so particles would be accelerated on average. This random process is now called 2nd order Fermi acceleration, because the mean energy gain per "bounce" is dependent on the "mirror" velocity squared.
Bell (1978) and Blandford and Ostriker (1978) independently showed that Fermi acceleration by supernova remnant (SNR) shocks is particularly efficient, because the motions are not random. A charged particle ahead of the shock front can pass through the shock and then be scattered by magnetic inhomogeneities behind the shock. The particle gains energy from this "bounce" and flies back across the shock, where it can be scattered by magnetic inhomogeneities ahead of the shock. This enables the particle to bounce back and forth again and again, gaining energy each time. This process is now called 1st order Fermi acceleration, because the mean energy gain is dependent on the shock velocity only to the first power.
Asteroid or Meteor: What's the Difference? | NASA Space Place – NASA Science for Kids
When they land on Earth, they are called meteorites.

A scientist investigates a meteorite that landed in Sudan's Nubian Desert in 2008. Image credit: NASA
NASA’s Johnson Space Center has a collection of meteorites that have been collected from many different locations on Earth. The collection acts as a meteorite library for scientists. By studying different types of meteorites, scientists can learn more about asteroids, planets and other parts of our solar system.
Because asteroids formed in the early days of our solar system nearly 4.6 billion years ago, meteorites can give scientists information about what the solar system was like way back then!

Related Resources for Educators

Astromaterials 3D: A virtual library for exploration and research of
NASA's space rock collections
Asteroid Resources from NASA JPL Education

 	article last updated June 30, 2021
 

More about asteroids, meteors, and comets!

What Is an Asteroid?

What Is a Meteor Shower?

All About Comets

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What Is a Meteor Shower?

What Is an Asteroid?

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Virtual Vocabulary | NASA eClips
PPE for firefighters includes a fire helmet; fire-resistant pants, jackets and gloves; and steel-toed, waterproof boots. topprecipitation - Precipitation is water in the atmosphere that falls to Earth as rain, snow, hail, sleet, or freezing rain. topprecision - Precision is the condition of being exact and accurate. toppressure - Pressure is the force per unit area. Even though you can't feel it, air has pressure. Air molecules move continuously. The more times they bump into each other or a surface, the greater the pressure. Air pressure is increased by: 1. increasing the number of molecules in the same amount of space (volume); 2. increasing the temperature (it makes the air molecules move faster); or 3. decreasing the volume. topprobability - Probability is the likelihood or chance that something will occur. topprocess - A process is the continuous action or a series of changes taking place in a definite manner. topprojectile - A projectile is any object that is thrown or otherwise launched. It is affected by Earth's gravity. A projectile may start at a given height and move toward the ground in an arc. Regardless of its path, a projectile will follow these rules:Projectiles maintain a constant horizontal velocity (in the absence of air resistance).On Earth, projectiles experience a constant vertical acceleration of 9.8 m/s2 (32 ft/s 2) downward (in the absence of air resistance). topprominence - A prominence is a huge column of relatively cool gas arcing out above the photosphere (the visible surface of the sun) and can be seen from Earth. topproperty - A property is a characteristic that can be observed or measured. topprototype - A prototype is an original or model on which something is based. toppulley - A pulley is a wheel with a rope, chain, or belt passed over it. A load is attached to one end of the rope and the other end is pulled. A single pulley lets you change the direction of the pull. A set of pulleys makes it possible to lift heavy loads with less effort.
What Is La Niña? | NASA Space Place – NASA Science for Kids
Drag the slider tool to see the differences between La Niña conditions and normal conditions in the Pacific Ocean.

Warm water moves west during a La Niña, and so do the clouds. This means that places like Indonesia and Australia can get much more rain than usual. And places like the southwestern United States can be very dry. La Niña weather conditions can also lead to more hurricanes and lightning in other parts of the world.
Thankfully, scientists can predict La Niña weather patterns up to a year before they occur. The GOES-R series of weather satellites can help weather forecasters map the increased lightning and issue earlier and more accurate warnings of severe weather.

What's the difference between El Niño and La Niña?
Both events start in the Pacific Ocean, but they are opposites in almost every other way! La Niña causes water in the eastern Pacific to be colder than usual. In the same region, El Niño can cause the water to be warmer than usual. So, areas that are hit with drought during La Niña years can get lots of rain in El Niño years!

 	article last updated May 29, 2020
 

More About Earth

What is El Niño?

How much water is on Earth?

Why is the sky blue?

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Astrophysics Science Division Colloquium Series Schedule: Spring 2024
The DGB dipole is determined from flux maps in narrow energy bands constructed from 13 yr of observations by the Large Area Telescope (LAT) of the Fermi satellite. The γ-ray maps were clipped iteratively of sources and foregrounds similar to that done for the cosmic infrared background. The clipped narrow energy band maps were then assembled into one broad energy map out to the given energy starting at E = 2.74 GeV, where the LAT beam falls below the sky's pixel resolution. Next we consider cuts in Galactic latitude and longitude to probe residual foreground contaminations from the Galactic plane and center. In the broad energy range 2.74 < E < 115.5 GeV, the measured dipoles are stable with respect to the various Galactic cuts, consistent with an extragalactic origin. The γ-ray sky's dipole/monopole ratio is much greater than that expected from the DGB clustering component and the Compton-Getting effect origin with reasonable velocities. At (6.5-7)% it is similar to the Pierre Auger UHECRs with EUHECR >8 EeV, pointing to a common origin of the two dipoles. However, the DGB flux associated with the found DGB dipole reaches parity with that of the UHECR around EUHECR < 1 EeV, perhaps arguing for a non-cascading mechanism if the DGB dipole were to come from the higher-energy UHECRs. The signal-to-noise ratio of the DGB dipole is largest in the 5-30 GeV range, possibly suggesting the γ-photons at these energies are the ones related to cosmic rays.

Revealing the Lifecycle of Interstellar Dust with Polarimetry
Brandon S. Hensley
JPL/Caltech
Tuesday, Feb 27, 2024

Abstract
Observations of polarized dust emission from the Planck satellite challenged our classical models of interstellar dust grains. In this talk, I will argue that initially distinct populations of carbonaceous and silicate stardust get rapidly homogenized in the ISM into a composite material ("astrodust").
News and Events | Terra
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January 2023: “Antarctica’s Brunt Ice Shelf Finally Breaks“
The long-awaited break of the Chasm 1 rift in the Brunt Ice Shelf in Antarctica occurred on January 22, 2023, spawning Iceberg A-81, approximately 1550 square kilometers in size, as observed by NASA’s Terra satellite on January 24, 2023, marking a culmination of the rift’s growth since the 1970s.

February 2023: “Ex-cell-ent Clouds off Chile’s Coast“
Satellites like Terra have shown that marine stratocumulus clouds, covering about 23% of global oceans, exhibit open-celled and closed-cell formations. Open-celled clouds generate rainfall, while closed-cell clouds produce little rain. Local air quality, influenced by factors like smoke and aerosols, can impact the transition between these cloud types. Recent Terra imagery captured off the coast of Chile highlight the intricate structures of these clouds.

March 2023: “A Surge of Floodwater for Owens Lake“
In March 2023, California’s historically dry Owens Lake experienced an unprecedented rainfall event that led to the collapse of three sections of the Los Angeles Aqueduct, causing floodwaters to flow over the lakebed. The first of its kind, this breach prompted the Los Angeles Department of Water and Power to open floodwater spill gates for repairs. Terra satellite imagery on March 25, 2023, revealed the transformed landscape and highlights the importance of planning for future climate change impacts to water cycle extremes in the region.

April 2023: “A Massive Seaweed Bloom in the Atlantic“
Last spring, the “Great Atlantic Sargassum Belt” witnessed its largest recorded Sargassum bloom, estimated at 13 million tons by University of South Florida researchers using NASA’s Terra and Aqua satellites. The seaweed, vital for ocean health, poses challenges near coasts, affecting marine species and tourism. The ongoing growth trend since 2011, influenced by nutrient inputs and changing ocean patterns, raises concerns for major beaching events along the Caribbean and Florida’s east coast. 

May 2023: “Retreat at Petermann Glacier“
How Do We Launch Things Into Space? | NASA Space Place – NASA Science for Kids
How Do We Launch Things Into Space? | NASA Space Place – NASA Science for Kids

launching-into-space

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How Do We Launch Things Into Space?

The Short Answer:

	We launch things into space by putting them on rockets with enough fuel — called propellant — to boost them above most of Earth’s atmosphere. Once a rocket reaches the right distance from Earth, it releases the satellite or spacecraft.
	

Watch this video about how we launch things into space! Click here to download this video (1920x1080, 48 MB, video/mp4).

We launch satellites and spacecraft into space by putting them on rockets carrying tons of propellants. The propellants give the rocket enough energy to boost away from Earth’s surface. Because of the pull of Earth’s gravity, largest, heaviest spacecraft need the biggest rockets and the most propellent.

The GRACE Follow-On spacecraft launched into orbit in May 2018. Credit: NASA/Bill Ingalls

How does a rocket lift off?
More than 300 years ago, a scientist named Isaac Newton laid out three basic laws that describe the way things move. One of the laws says that for every action, there is an equal and opposite reaction. This is the most important idea behind how rockets work.

Credit: NASA/JPL-Caltech

If you see pictures or videos of a launch, you’ll see exhaust streaming out the bottom of the rocket. Exhaust is the flames, hot gases and smoke that come from burning the rocket’s propellants.
The exhaust pushes out of a rocket’s engine down toward the ground. That’s the action force. In response, the rocket begins moving in the opposite direction, lifting off the ground. That’s the reaction force.

Once a rocket launches, will it keep going?
It’s not that simple. Earth’s gravity is still pulling down on the rocket. When a rocket burns propellants and pushes out exhaust, that creates an upward force called thrust.
Taking a Measure of Sea Level Rise: Ice Height
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Watching the Rivers Flow on Greenland
A summer field campaign examines the hydrology of the water streaming across the top of the ice sheet.

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Astrolabe Glacier and Unbalanced Ice
Located in East Antarctica, Astrolabe Glacier streams out from the interior of Antarctica to dump ice into the sea. 

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Snow and Ice

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HOMEGETTING STARTEDFOR EDUCATORSSPACE WEATHER DATA

Space Weather Action Center

SPACE WEATHER ACTION CENTER

 

Above: This is an example of a Space Weather Report.
Imagine being able to monitor the progress of an entire solar storm from the time it erupts from our sun until it sweeps past our small planet effecting enormous changes in our magnetic field. Now imagine being able to do all of this from your classroom-based Space Weather Action Center (S.W.A.C.)! By following the basic steps in the Instructional Guide your class will soon be on its way to accessing, analyzing and recording NASA satellite and observatory data. You will also want to download the 'step-by-step' Educator's Setup Guide where you will find a variety of recommendations and diagrams showing you how to construct a fully functional SWAC inside your classroom while keeping potential limitations on classroom space and technology in mind.
Once established your class will be ready to move into the second cross-disciplinary phase of the program where they will transform their journal data into real S.W.A.C. news reports! We've made this phase easy by providing an adaptable SWAC script! All they have to do is fill in the missing pieces based on the data collected in their student journals. In the S.W.A.C. Setup Guide we have suggested several very inexpensive alternative methods by which you can produce multimedia Space Weather Action Reports.

Downloadable Materials

Above: This is an example of a Space Weather Action Center that you might set up in your classroom.
We have recently updated all of these materials to Version 4 (V4). Please make sure you have the latest versions.
FLIP CHARTS
With these Flip Charts your students will be able to analyze data and predict a solar storm with ease and accuracy by following the step by step instructions. Each Flip Chart contains introductory space weather information and tips on data analysis and website navigation!

Printable Flip Charts

Sunspot Regions Flip Chart V4 (228K)
Storm Signals Flip Chart V4 (142K)
Magnetosphere Flip Chart V4 (788K)
Growing Beyond Earth Annual Student Research Symposium - NASA Science
It also helped eager aurora chasers get a better view.Article4 days ago 5 min readHow NASA Tracked the Most Intense Solar Storm in DecadesArticle1 week ago 3 min readResearchers Develop ‘Founding Document’ on Synthetic Cell DevelopmentCells are the fundamental units of life, forming the variety of all living things on Earth as individual cells and multi-cellular organisms. To better understand how cells perform the essential functions of life, scientists have begun developing synthetic cells – non-living bits of cellular biochemistry wrapped in a membrane that mimic specific biological processes. The […]Article3 weeks ago Keep ExploringDiscover More Topics From NASAJames Webb Space TelescopePerseverance RoverParker Solar ProbeJunoReturn to topThe National Aeronautics and Space AdministrationNASA explores the unknown in air and space, innovates for the benefit of humanity, and inspires the world through discovery.About NASA's MissionJoin UsHomeNews & EventsMultimediaNASA+MissionsHumans in SpaceEarth & ClimateThe Solar SystemThe UniverseScienceAeronauticsTechnologyLearning ResourcesAbout NASANASA en EspañolFollow NASAMore NASA Social AccountsNASA NewslettersSitemapFor MediaPrivacy PolicyFOIANo FEAR ActOffice of the IGBudget & Annual ReportsAgency Financial ReportsContact NASAAccessibilityPage Last Updated:16 hours agoPage Editor:SMD Content EditorsResponsible NASA Official for Science:Dana Bolles
NASA - Sun-Earth Day 2010
Magnetic fields and electric fields are aspects of a more basic field in nature called the electromagnetic field.
A toy magnet produces more force on a paperclip than the entire mass of Earth through its gravity.

SPACE WEATHER FACTS

Solar flares can sometimes heat the solar surface to temperatures of 80 million F - far hotter that the sun's core!
The fastest coronal mass ejection was recorded on August 4, 1972 and traveled from the sun to earth in 14.6 hours - a speed of nearly 10 million kilometers per hour!
On April 8, 1947, the largest sunspot in modern history reached its maximum size of over 330 times Earth's area.
The most powerful solar flare in the last 500 years occurred on September 2, 1859 and was sighted by two astronomers who happened to be looking at the sun at exactly the right time!
Between May 10-12, 1999, the solar wind nearly vanished, causing Earth's magnetosphere to expand in volume by over 100 times!
A typical CME can be millions of kilometers in size, but have the mass of only a small mountain!
Some sunspots are cool enough that water vapor can form at a temperature of 1,550 C.
The most powerful aurora can generate over 1 trillion watts of power.
The March 13, 1989 Quebec blackout, the result of a major geomagnetic storm, caused a $6 billion loss to the Canadian economy.
During intense solar flares, astronauts see bright flashing streaks of light as a result of high-energy particles zipping through their eyeballs.
The largest, single, challenge for astronauts traveling to Mars will be to overcome exposure to solar storms and radiation.
Space Weather Forecasting costs only $5 million a year, but supports over $500 billion in annual revenue from the satellite and electrical power industries.
Over $2 billion in satellite technology was damaged or destroyed during the last sunspot cycle.
A major solar 'superstorm' such as the one in 1859 could cost $30 billion a day to the US electrical power grid, and up to $70 billion to the satellite industry.
The August 4, 1972 solar flare was so powerful that, by some estimates, a spacesuited astronaut would have received a lethal does of radiation.
Earth Science in Action - NASA Science
Article5 min readNASA Selects New Aircraft-Driven Studies of Earth and Climate ChangeQuantifying Bangladesh’s Vast Water ResourcesBangladesh is a small country with a huge amount of water that moves over its surface. The Ganges, Brahmaputra, and Meghna rivers form the world’s largest river delta as they flow south to the Bay of Bengal and ultimately into the Indian Ocean. Just how much water fills these vast floodplains?Read MoreHow NASA Helps Fight Mosquitoes from SpaceMosquitoes are sometimes hard to spot, even with the human eye. But NASA can help track these disease-spreading insects with satellite data. Earth observations help pinpoint environmental conditions where mosquito populations will thrive.Read MoreEnabling Earth Science at NASAImpacts And BenefitsNASA Applied SciencesThe Applied Sciences Program works with individuals and institutions worldwide to inform decision-making, enhance quality of life and strengthen the economy.Learn MoreNASA and AgricultureIn the satellite era, Earth observing data has increasingly become part of the food farming process. With observations from space and aircraft, combined with high-end computer modeling, NASA scientists work with partner agencies, organizations, farmers, ranchers, fishermen, and decision makers to share our understanding of the relationship between the Earth system and the environments that provide us food.Ensuring Food SecurityNASA promotes the use of Earth observations to strengthen food security, support market stability and protect human livelihoods. Together with partners in the United States and around the world, we help bolster food security, improve agricultural resilience and reduce price volatility for vulnerable communities.Read MoreNASA At Your Table: The Space Agency’s Surprising Role in AgricultureEverybody needs to eat.