vania-janet/multiturn-rag-retrieval-data huggingface dataset:
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An international mission launched on June 11, 2008, GLAST studies the universe in the energy range 10 keV - 300 Gev. In August 2008, NASA renamed the mission the Fermi Gamma-ray Space Telescope.

 Tell me more about GLAST.

Gamma Ray Imaging Platform (GRIP)
A balloon-borne gamma-ray telescope made by a group at the California Institute of Technology. It has had many successful flights.
Gamma Ray Imaging Spectrometer (GRIS)
A balloon-borne instrument which uses germanium detectors for high resolution gamma-ray spectroscopy.

 Tell me more about GRIS.

gas
One of the three states of matter, in which atoms, molecules, or ions move freely and are not bound to each other. In astronomy, it usually refers to hydrogen or helium.
general relativity
The geometric theory of gravitation developed by Albert Einstein, incorporating and extending the theory of special relativity to accelerated frames of reference and introducing the principle that gravitational and inertial forces are equivalent. The theory has consequences for the bending of light by massive objects, the nature of black holes, and the fabric of space and time. 
Giant Molecular Cloud (GMC)
Massive clouds of gas in interstellar space composed primarily of hydrogen molecules (two hydrogen atoms bound together), though also containing other molecules observable by radio telescopes. These clouds can contain enough mass to make several million stars like our Sun and are often the sites of star formation.
Ginga
The third Japanese X-ray mission, also known as Astro-C.

 Tell me more about Ginga.

globular cluster
A spherically symmetric collection of stars which shared a common origin. The cluster may contain up to millions of stars spanning up to 50 parsecs. 
gravitational collapse
When a massive body collapses under its own weight. (For example, interstellar clouds collapse to become stars until the onset of nuclear fusion stops the collapse.)
gravitational radius
See event horizon.
gravitational waves
Ripples in space-time caused by the motion of objects in the universe. The most notable sources are orbiting neutron stars, merging black holes, and collapsing stars. Gravitational waves are also thought to emanate from the Big Bang.
Hubble Captures a Bright Spiral in the Queen’s Hair - NASA Science
amp; Dark EnergyThe Solar System The SunMercuryVenusEarthThe MoonMarsJupiterSaturnUranusNeptunePluto &amp; Dwarf PlanetsAsteroids, Comets &amp; MeteorsThe Kuiper BeltThe Oort CloudSkywatchingEspañol CienciaAeronáuticaCiencias TerrestresSistema SolarUniversoScience All NASA ScienceEarth SciencePlanetary ScienceAstrophysics & Space ScienceThe Sun & HeliophysicsBiological & Physical SciencesLunar ScienceCitizen ScienceAstromaterialsAeronautics ResearchHuman Space Travel ResearchExploreSearchSubmitNews & EventsMultimediaNASA+2 min readHubble Captures a Bright Spiral in the Queen’s HairNASA Hubble Mission TeamGoddard Space Flight CenterMay 24, 2024ArticleThis Hubble Space Telescope image showcases the bright spiral galaxy NGC 4689.ESA/Hubble & NASA, D. Thilker, J. Lee, and the PHANGS-HST TeamThis NASA/ESA Hubble Space Telescope image shows the jewel-bright spiral galaxy NGC 4689, which lies 54 million light-years from Earth in the constellation Coma Berenices. This constellation has the distinction of being the only one of the 88 constellations officially recognized by the International Astronomical Union (IAU) as one named after the historical figure, Queen Berenice II of Egypt. The Latin word ‘coma’ references her hair, which means that NGC 4689 lies in the hair of a queen. Some people of Berenice’s time would have meant this quite literally, as the story goes that her court astronomer thought that a missing lock of Berenice’s hair had been catasterised (a word meaning ‘placed amongst the stars’) by the gods: hence the name of the constellation, Coma Berenices.NGC 4689 holds an interesting — albeit less royal — place in modern astronomy. The universe is so incredibly vast that at a distance of 54 million light-years NGC 4689 is relatively nearby for a galaxy. This image includes data from two sets of observations, one made in 2019, the other in 2024 , and both are part of programs that observed multiple ‘nearby’ galaxies.
Galaxies Actively Forming in Early Universe Caught Feeding on Cold Gas - NASA Science
“The next step is to build large statistical samples of galaxies and quantify the prevalence and prominence of their features in detail,” Heintz said.The researchers’ findings were possible thanks to Webb’s Cosmic Evolution Early Release Science (CEERS) Survey, which includes spectra of distant galaxies from the telescope’s NIRSpec (Near-Infrared Spectrograph), and was released immediately to support discoveries like this as part of Webb’s Early Release Science (ERS) program.This work has been published in the May 24, 2024 issue of the journal Science.The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).DownloadsRight click any image to save it or open a larger version in a new tab/window via the browser's popup menu.View/Download full resolution images for this article from the Space Telescope Science Institute.Research Paper: published in the May 24, 2024 issue of the journal Science.Media ContactsLaura Betz - laura.e.betz@nasa.gov, Rob Gutro - rob.gutro@nasa.govNASA’s Goddard Space Flight Center, Greenbelt, Md.Claire Blome cblome@stsci.edu, Christine Pulliam - cpulliam@stsci.eduSpace Telescope Science Institute, Baltimore, Md.Related InformationInfographic: Era of Reionization InfographicArticle: How Webb Can Study the Early UniverseVideo: Galaxies through TimeVideo: Scientists’ Perspective: Science SnippetsArticle: Galaxy BasicsArticle: Galaxy EvolutionMore Webb News - https://science.nasa.gov/mission/webb/latestnews/More Webb Images - https://science.nasa.gov/mission/webb/multimedia/images/Webb Mission Page - https://science.nasa.gov/mission/webb/Related
Are We Alone? - NASA Science
But so far, we have no evidence of life beyond Earth. Is life in the cosmos easily begun, and commonplace? Or is it incredibly rare?How big is the Milky Way galaxy? Make the jump to light-years as we cruise through our galaxy. VideoNASA/JPL-CaltechMore questions than answersIn the thousands of years humanity has been contemplating the cosmos, we are the first people to know one thing for sure: The stars beyond our Sun are teeming with planets. They come in many varieties, and a good chunk of them are around the size of Earth. Like most scientific questions, though, getting an answer to this one just breeds more questions: Which, if any, of these exoplanets harbors some form of life? How quickly does life get its start? And how long does it last?This artist's concept allows us to imagine what it would be like to stand on the surface of the exoplanet TRAPPIST-1f, located in the TRAPPIST-1 system in the constellation Aquarius, as of Feb 2017.Where is everybody?The universe's eerie silence has its own name – the "Fermi paradox." Physicist Enrico Fermi famously posed the question: "Where is everybody?" Even at slow travel speeds, the universe's billions of years of existence allow plenty of time for intelligent, technological lifeforms to traverse the galaxy. Why, then, is the cosmos so quiet?Meanwhile, exoplanet discoveries over the past two decades have filled in a few of the terms in the much-debated Drake Equation – a chain of numbers that might one day tell us how many intelligent civilizations we can expect to find. Most of its terms remain blank – the fraction of planets with life, with intelligent life, with detectable technology – but the equation itself suggests we might one day arrive at an answer. It feels at least a little more hopeful than Fermi's silence.We stand at a crossroads in the search for life. We've found thousands of planets in our Milky Way galaxy, a large fraction of them in Earth's size range and orbiting in their stars' "habitable zones" – the distance from the star at which liquid water could exist on the surface.
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The principle of quantum mechanics which implies that light (and, indeed, all other subatomic particles) sometimes act like a wave, and sometimes act like a particle, depending on the experiment you are performing. For instance, low frequency electromagnetic radiation tends to act more like a wave than a particle; high frequency electromagnetic radiation tends to act more like a particle than a wave.
wavelength
The distance between adjacent peaks in a series of periodic waves. Also see electromagnetic spectrum.
white dwarf
A star that has exhausted most or all of its nuclear fuel and has collapsed to a very small size. Typically, a white dwarf has a radius equal to about 0.01 times that of the Sun, but it has a mass roughly equal to the Sun's. This gives a white dwarf a density about 1 million times that of water!

 Tell me more about white dwarfs

Wien's displacement law
For a blackbody, the product of the wavelength corresponding to the maximum radiancy and the thermodynamic temperature is a constant. As a result, as the temperature rises, the maximum of the radiant energy shifts toward the shorter wavelength (higher frequency and energy) end of the spectrum.
WIMP (weakly interacting massive particle)
Theoretical subatomic particles that do not respond to electromagnetic force or interact through strong nuclear force, but would interact only through weak nuclear force and gravity. Because of these properties, they are difficult to detect, and are therefore considered "dark" — hence, WIMPs are a possible form of dark matter.
WMAP (Wilkinson Microwave Anisotropy Probe)
A NASA satellite designed to detect fluctuations in the cosmic microwave background. From its initial results published in Feb 2003, astronomers pinpointed the age of the universe, its geometry, and when the first stars appeared.

 Tell me more about WMAP

WWW
The World Wide Web -- a loose linkage of Internet sites which provide data and other services from around the world.
X
XMM-Newton
The X-ray Multi-Mirror Mission, launched by the European Space Agency in 1999. Observation targets include quasars, gamma-ray bursts, galaxy clusters and comets.
Dark Matter & Dark Energy - NASA Science
ExoplanetsThe Search for Life in the UniverseStarsGalaxiesBlack HolesThe Big BangDark Matter &amp; Dark EnergyThe Solar System The SunMercuryVenusEarthThe MoonMarsJupiterSaturnUranusNeptunePluto &amp; Dwarf PlanetsAsteroids, Comets &amp; MeteorsThe Kuiper BeltThe Oort CloudSkywatchingEspañol CienciaAeronáuticaCiencias TerrestresSistema SolarUniversoScience All NASA ScienceEarth SciencePlanetary ScienceAstrophysics & Space ScienceThe Sun & HeliophysicsBiological & Physical SciencesLunar ScienceCitizen ScienceAstromaterialsAeronautics ResearchHuman Space Travel ResearchExploreSearchSubmitNews & EventsMultimediaNASA+UniverseCosmic HistoryBuilding BlocksForcesGalaxiesOverviewTypesEvolutionLarge Scale StructuresBlack HolesOverviewTypesAnatomyBlack Hole WeekStarsOverviewTypesMultiple Star SystemsPlanetary SystemsExoplanetsExplorationSensing the UniverseTelescopes 101ObservatoriesMoreNewsDeep DivesQuick ReadsMultimediaGlossaryExplore This SectionUniverseGalaxiesBlack HolesStarsExoplanetsExplorationMoreDark Matter & Dark EnergyDiscover the universe's building blocks – matter, dark matter, and dark energy.OverviewEverything scientists can observe in the universe, from people to planets, is made of matter. Matter is defined as any substance that has mass and occupies space. But there’s more to the universe than the matter we can see.
Types - NASA Science
When observed in the infrared, some reveal bright emission from the donut-shaped torus. Some also emit X-rays. Seyfert galaxies tend to have lower radio luminosities, although some produce radio jets.Scientists divide Seyferts into two classes. Type I Seyfert galaxies display unusual features in their visible light that imply rapid motion near the accretion disk. Type II Seyferts show features that imply much slower motion. However, this distinction may result from different viewing angles into the centers of these galaxies.QuasarsThis Hubble Space Telescope image reveals a bright starlike glow in the center of active galaxy Markarian 231, the nearest quasar to Earth.NASA, ESA, the Hubble Heritage Team (STScI/AURA)-ESA/Hubble Collaboration, and A. Evans (University of Virginia, Charlottesville/NRAO/Stony Brook University)Quasars are the most luminous type of active galaxy. They emit light across the electromagnetic spectrum, produce powerful particle jets, and can radiate thousands of times the energy emitted by a galaxy like the Milky Way. The nearest quasar, called Markarian 231, is located some 600 million light-years away, but we see many more quasars the farther we look.Scientists have identified over 1 million quasars, with the farthest one currently known lying about 13 billion light-years away. Since light takes time to travel, scientists can use light from these galaxies as a way to peer back in time to study black hole growth and galaxy evolution. Merging galaxies in the young universe may provide the fuel to power the enormous energy output of quasars, but when the feeding frenzy ends, the black hole cannot maintain it. It’s thought that quasar activity may be episodic and that this entire phase may last only about 10 million years.BlazarsMarkarian 421, imaged here by the National Science Foundation’s Sloan Digital Sky Survey, is one of the closest blazars to Earth.Sloan Digital Sky SurveyBlazars produce light across the electromagnetic spectrum. Their powerful jets point almost directly at Earth, so they appear brighter than other active galaxies.
Cosmic Times


Cosmic Times

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Gravity bending starlight!
A solar eclipse confirms that Einstein's theory of gravity, not Newton's, correctly predicts the bending of starlight.

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Our expanding universe!
Hubble builds on his earlier discovery that the Milky Way Galaxy is but one of many galaxies in our Universe to find that the Universe is expanding.

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Einstein's death!
The debate rages between whether the Big Bang and Steady State correctly describes the origin of the universe.

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Light from the Big Bang!
Penzias and Wilson discover the Cosmic Microwave Background, the remnant radiation from the very early universe, which makes the case for the Big Bang Theory.

More 1965 News  →

The universe's baby picture!
The COBE mission measures fluctuations in the Cosmic Microwave Background, which explain structure in our universe and confirm the role of inflation.

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Dark energy!
The supernova distance scale leads to the discovery of dark energy in 1997, a puzzling new component of our universe whose nature remains a mystery in 2006.

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Meet the Cosmic Times Team

A service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Andy Ptak (Director), within the Astrophysics Science Division (ASD) at NASA/GSFC

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Printed Product Downloads | NASA Space Place – NASA Science for Kids
Each wavelength reveals something different about the galaxy. The back of poster explains how different telescopes that detect different wavelengths are all necessary in order for us to begin to understand galaxies, stars, planets, and the evolution of the universe. 
 Full-dimension .pdf of poster (33.5 x 26 inches).

The North America Nebula. A stunning image in infrared and visible light shows a region of stars and dusty clouds that are hidden in visible light alone. Back of poster has nine 8-1/2x11-inch panels that explain the electromagnetic spectrum and infrared astronomy, including the importance of infrared for studying galaxies and the distant universe, as well as planets. The famous experiment in which Sir Frederick William Herschel discovered infrared light is included as a classroom activity.
 Full-dimension .pdf of poster (26.5 x 34 inches).

Spitzer poster: Eta Carinae star forming region. Beautiful glowing pillars of dense gas and dust in this Spitzer infrared image clearly reveal areas where new stars are forming. Articles on back of poster explain about the image, about infrared light, and infrared astronomy. It also includes a classroom version of Sir Frederick Herschel's 1800 experiment in which he discovers invisible infrared light.
 Full-dimension .pdf of front (33 x 25.5 inches).
 8-1/2x11 printable .pdf of front.

Spitzer Poster: Multiwavelength Andromeda Galaxy. Three images of the beautiful spiral Andromeda Galaxy demonstrate the discoveries scientists are making by observing galaxies in many different wavelengths of light. The top image is in visible light. The middle image is a composite of wavelengths that are emitted by stars and active star-forming regions. The bottom image is a composite of wavelengths that highlight the gas and dust in the galaxy. Herschel's discovery of infrared light and Ritter's discovery of ultraviolet light are both described as experiments to be done in the classroom.
 Full-dimension .pdf of front (25.5 x 22 inches).
 8-1/2x11 printable .pdf of front.

Spitzer litho: Bubble-blowing stars at the center of the Milky Way

 Spitzer litho: RCW 86, a Supernova Footprint
What Is a Supernova? | NASA Space Place – NASA Science for Kids
When a massive star runs out of fuel, it cools off. This causes the pressure to drop. Gravity wins out, and the star suddenly collapses. Imagine something one million times the mass of Earth collapsing in 15 seconds! The collapse happens so quickly that it creates enormous shock waves that cause the outer part of the star to explode!
Usually a very dense core is left behind, along with an expanding cloud of hot gas called a nebula. A supernova of a star more than about 10 times the size of our sun may leave behind the densest objects in the universe—black holes.

The Crab Nebula is the leftover, or remnant, of a massive star in our Milky Way that died 6,500 light-years away. Astronomers and careful observers saw the supernova in the year 1054. Image credit: NASA, ESA, J. Hester and A. Loll (Arizona State University)
A second type of supernova can happen in systems where two stars orbit one another and at least one of those stars is an Earth-sized white dwarf. A white dwarf is what's left after a star the size of our sun has run out of fuel. If one white dwarf collides with another or pulls too much matter from its nearby star, the white dwarf can explode. Kaboom!

In this illustration, a white dwarf pulls matter from a companion star. Eventually, this will cause the white dwarf to explode. Image credit: STScI
How bright are supernovas?
These spectacular events can be so bright that they outshine their entire galaxies for a few days or even months. They can be seen across the universe.

How common are supernovas?
Not very. Astronomers believe that about two or three supernovas occur each century in galaxies like our own Milky Way. Because the universe contains so many galaxies, astronomers observe a few hundred supernovas per year outside our galaxy. Space dust blocks our view of most of the supernovas within the Milky Way.

What can we learn from supernovas?
Scientists have learned a lot about the universe by studying supernovas.
Hubble Space Telescope - NASA Science
Learn MoreJets emerge from the cocoon of a newly forming star to blast across space, slicing through the gas and dust of a shining nebula.NASA, ESA, and K. Stapelfeldt (NASA JPL); Image Processing: Gladys Kober (NASA/Catholic University of America)Hubble’s Universe121 ImagesGo To GalleryGo To GalleryHubble ImagesView Images of Hubble Science, Servicing Missions, Operations, Spacecraft, Anniversaries, and more. Explore More HubbleOn The Shoulders of a GiantWhat's the same and what's different? Compare these two NASA flagship missions.Read MoreHubble Science HighlightsHubble has affected every area of astronomy. Its most notable scientific discoveries reflect the broad range of research and the breakthroughs it has achieved.Read MoreExplore the Night SkyYour backyard telescope and binoculars may not have the capabilities of Hubble, but you can still see amazing objects. Compare what you see with the images Hubble has taken.Read MoreHubble E-booksInvestigate the mysteries of the universe with Hubble. Learn Hubble's history. E-books dive deeper into Hubble discoveries and more.Read MoreKeep ExploringDiscover More NASA MissionsJames Webb Space TelescopeNASA HistoryParker 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:5 days agoPage Editor:SMD Content EditorsResponsible NASA Official for Science:Dana Bolles
Imagine the Universe!
A keV (or kiloelectron volt) is equal to 1000 electron volts. An MeV is equal to one million electron volts. A GeV is equal to one billion (109) electron volts. A TeV is equal to a million million (1012) electron volts.
elements
The fundamental kinds of atoms that make up the building blocks of matter, which are each shown on the periodic table of the elements. The most abundant elements in the universe are hydrogen and helium. These two elements make up about 80% and 20% of all the matter in the universe respectively. Despite comprising only a very small fraction the universe, the remaining heavy elements can greatly influence astronomical phenomena. About 2% of the Milky Way's disk is comprised of heavy elements.
ellipse
Oval. That the orbits of the planets are ellipses, not circles, was first discovered by Johannes Johannes Kepler the careful observations by Tycho Brahe.
emission
The production of light, or more generally, electromagnetic radiation by an atom or other object.
emission line spectrum
A spectrum consisting of bright lines at certain wavelengths separated by dark regions in which there is no light.
erg/sec
A form of the metric unit for power. It is equal to 10-10 kilowatts (see scientific notation).
EUD
Exploration of the Universe Division, located at NASA's Goddard Space Flight Center. The scientists, programmers and technicians working here study the astrophysics of objects which emit cosmic ray, x-ray and gamma-ray radiation.
event horizon
The distance from a black hole within which nothing can escape. 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