vania-janet/multiturn-rag-retrieval-data huggingface dataset:
Guidelines for using NASA Images and Media Guidelines
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Hubble Space Telescope - NASA Science
Hubble images captured today, show what the objects looked like years ago!Read MoreNew Messier Catalog ImagesWe have added new images to Hubble's Messier Catalog of celestial objects. Explore the catalog for objects you can see through a small telescope or binoculars from a dark sky site.Explore MoreNature's Boost: Gravitational LensesThe gravity of massive objects warps space and time, creating a lens that provides astronomers with a powerful tool to extend our view into previously unseen regions of the universe.Read MoreWhat Did Hubble See on Your Birthday?Hubble explores the universe 24 hours a day, 7 days a week. That means it has observed some fascinating cosmic wonder every day of the year, including on your birthday.Check Out Your Birthday!More Hubble Online ActivitiesSee AllWhat is Hubble Observing?See the area of sky Hubble is investigating.Name that Nebula!Match nebulae with their namesHubble's SkymapGet a Hubble's-eye-view of cosmic objectsHubble Spacecraft 360 Degree TourVirtually Tour Hubble in orbitHubble Astronaut Fun FactsPlay this trivia game and test your knowledge!Control Center 360-Degree TourTake a virtual tour of Hubble's operations centerUnable to render the provided sourceOverviewImpactScienceObservatoryA New View of the UniverseHow did a telescope become a household name and change how we look at the cosmos forever?With over 1.5 million observations and 20,000+ papers published on its discoveries, Hubble is the most productive science mission in the history of NASA. Yet the story of Hubble’s success starts before NASA even existed. It includes adversity, human ingenuity, heroic spacewalks, risk taking, and discovery. Learn the background of one NASA’s most famous missions.Learn MoreAstronauts aboard Space Shuttle Atlantis snapped a still photo of the Hubble Space Telescope after it was grappled by the shuttle's Canadian-built Remote Manipulator System during Servicing Mission 4.
Virtual Vocabulary | NASA eClips
topgravitational force - Gravitational force is the force of attraction between all masses in the universe. topgravitational pull - Gravitational pull is the attraction that all masses in the universe exert on one another. The gravitational pull of the Moon on Earth's oceans causes tides. topgravity - Gravity is a force between objects based on their masses and the distance between the objects. The force of gravity on the moon is less than the force of gravity on Earth because the moon has only 1/6 the mass of Earth. Earth's gravity is described as 1g. topGreat Salt Lake - The Great Salt Lake, located in several wide basins in Utah, is the largest natural lake west of the Mississippi River. The Great Salt Lake is approximately 75 miles long and about 35 miles wide. Salt is brought in by tributaries. As water in the Lake evaporates, salt is left behind. The salinity of the lake is 270 parts per thousand as compared to the average salinity of the world ocean, which is 35 parts per thousand. topgreenhouse gases - Greenhouse gases are gases that contribute to the warming of the Earth's atmosphere by reflecting solar radiation from Earth's surface. Carbon dioxide, ozone, and water vapor are examples of greenhouse gases. topground truth - Ground truthing is a validation process where a person on the ground (or sometimes in an airplane) makes a measurement of the same phenomenon a satellite is measuring, at the same time the satellite is measuring it. The two answers are compared to evaluate how well the satellite instrument is performing. The actual measurements taken on Earth are called "ground truth." tophhabitat - A habitat is the place where an organism is naturally found in an ecosystem. topheat - Heat is the amount of thermal energy absorbed, released, or transferred by a material. This is typically expressed as q, and is measured in joules (J). topHIAD - (Hypersonic Inflatable Aerodynamic Decelerators) HIADs are inflatable heat shield structures made up of incredibly strong, yet flexible fabric designed to maintain shape and withstand head during atmospheric reentry. tophighlands - Highlands are mountainous regions of land.
Virtual Vocabulary | NASA eClips
topnet force - The net force is the total of all of the forces acting on an object. These forces are vectors, which means they have direction as well as magnitude. topneutron star - A neutron star is the type of star formed when a massive star explodes as a supernova, leaving behind an ultra dense core. topnew Moon - A new Moon is the phase of the Moon in which no part of the Moon is visible from Earth. topNewton's Law of Gravitation - The force of attraction between two masses where its strength depends on their masses and the distance between them. topNewton's Second Law of Motion - Newton's Second Law of Motion states that the acceleration of an object depends on the mass of the object and the amount of force applied. The first part of the law explains why the acceleration of a 3 kg bowling ball would be greater than that of a 7 kg bowling ball. The second part of the law explains why the acceleration of the 7 kg bowling ball will be greater if a larger force is applied to it. topNewtonian fluid - A Newtonian fluid is a fluid that reacts the same way no matter how much stress, or force, is applied to it. topnitrogen - Nitrogen is a naturally occurring colorless, odorless, tasteless gas element. Nitrogen makes up about 78% of the Earth's atmosphere. It makes up proteins and is essential for life. topnon-Newtonian fluid - A non-Newtonian fluid is a fluid that changes behavior depending on the amount of stress, or force, applied to it. topnondestructive evaluation - Nondestructive evaluation (or nondestructive testing) is a variety of analysis techniques used in the science and technology industry to evaluate the properties of a material, component or system without causing damage. topnonliving - Nonliving is not living, inanimate, or no longer alive or characterized by life. topnucleus - The nucleus of the comet is the solid, rocky part of the comet. topnutrients - Nutrients are substances that an organism (plant or animal) needs in order to survive and grow.
Forces - NASA Science
The weak force can turn a down quark in a neutron into an up quark, which would change the neutron into a proton and switch its electric charge from neutral to positive. If that neutron were in the nucleus of an atom, the change to a proton would turn that atom into a different type of element. Such reactions are happening all the time in our Sun, giving it the energy to shine. This type of action also occurs in radioactive decay, which happens when atoms spontaneously shed energy and subatomic particles.The weak force works on the smallest distance scales, another 1,000 times smaller than the strong force. It is about a million times weaker than the strong force, too, though it is still considerably stronger than gravity.Keep ExploringDiscover More Topics From NASAGalaxiesBlack HolesStarsExoplanetsReturn 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:2 weeks agoPage Editor:SMD Content EditorsResponsible NASA Official for Science:Dana Bolles
The Imagine the Universe! Team
The Imagine the Universe! Team

National Aeronautics and Space Administration
Goddard Space Flight Center

Imagine the Universe!

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The Imagine the Universe! Team

 

The Imagine Team

Who Writes this Stuff ??

 The materials found in the Imagine the Universe! web site
are written by a dedicated group of astronomers and
programmers who work at NASA's
Goddard Space Flight Center. Some members of this jolly group spend their
days recovering data from old X-ray and gamma-ray satellites and making it
available to the public for use again. Others spend their time helping
various astronomers plan and interpret observations obtained with current
satellite missions such as
XMM,
INTEGRAL,
Suzaku, 
Swift, Fermi, and the Rossi
X-ray Timing Explorer
(RXTE), and others plan for upcoming missions. All of these activities entail
astronomers
and programmers working together to develop sophisticated computer software
and databases which are made accessible via the web. Since 1996 we have provided educational
materials and resources to a broader
community of students, teachers, and the general public who wish to know more
about the wondrous Universe.

Image Credit: NASA

[Left to Right: (Front Row) Sara Mitchell, Meredith
Gibb, Anita Krishnamurthi;
(Middle Row) Beth Barbier, Mike Arida, Koji Mukai, Jim Lochner, Karen Smale, Barbara
Mattson;
(Back Row) Pat Keeney, Hans Krim, Dave Chuss, George Gliba, Duilia
De Mello]

Contributors (not all are pictured above):

Jim Lochner -- Imagine the Universe's numero uno. He keeps it running
and keeps everyone happy.
Imagine the Universe!
Astronomers often express units for other objects in terms of solar units, which makes the resulting numbers smaller and easier to deal with.
Lagrange, Joseph (1736 - 1813)
A French mathematician of the eighteenth century. His work Mecanique Analytique (Analytical Mechanics; 1788) was a mathematical masterpiece. It contained clear, symmetrical notation and covered almost every area of pure mathematics. Lagrange developed the calculus of variations, established the theory of differential equations, and provided many new solutions and theorems in number theory. His classic Theorie des fonctions analytiques laid some of the foundations of group theory. Lagrange also invented the method of solving differential equations known as variation of parameters.

 Show me a picture of Joseph Lagrange!

Lagrange points
Points in the vicinity of two massive bodies (such as the Earth and the Moon) where each others' respective gravities balance. There are five, labeled L1 through L5. L1, L2, and L3 lie along the centerline between the centers of mass between the two masses; L1 is on the inward side of the secondary, L2 is on the outward side of the secondary; and L3 is on the outward side of the primary. L4 and L5, the so-called Trojan points, lie along the orbit of the secondary around the primary, sixty degrees ahead and behind of the secondary.
L1 through L3 are points of unstable equilibrium; any disturbance will move a test particle there out of the Lagrange point. L4 and L5 are points of stable equilibrium, provided that the mass of the secondary is less than about 1/24.96 the mass of the primary. These points are stable because centrifugal pseudo-forces work against gravity to cancel it out.
laser
Laser is an acronym for Light Amplification by Stimulated Emission of Radiation. It's a device that produces a coherent beam of optical radiation by stimulating electronic, ionic, or molecular transitions to higher levels so that when they return to lower energy levels they emit energy.
LHEA
Laboratory for High Energy Astrophysics, located at NASA's Goddard Space Flight Center.
Forces - NASA Science
Forces - NASA Science

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Imagine the Universe!
Newton's second law of motion
	For an unbalanced force acting on a body, the acceleration produced is proportional to the force impressed; the constant of proportionality is the inertial mass of the body.
	Newton's third law of motion
	In a system where no external forces are present, every action force is always opposed by an equal and opposite reaction.

noise
The random fluctuations that are always associated with a measurement that is repeated many times over. Noise appears in astronomical images as fluctuations in the image background. These fluctuations do not represent any real sources of light in the sky, but rather are caused by the imperfections of the telescope. If the noise is too high, it may obscure the dimmest objects within the field of view.
nova (plural: novae)
A star that experiences a sudden outburst of radiant energy, temporarily increasing its luminosity by hundreds to thousands of times before fading back to its original luminosity.
nuclear fusion
A nuclear process whereby several small nuclei are combined to make a larger one whose mass is slightly smaller than the sum of the small ones. The difference in mass is converted to energy by Einstein's famous equivalence "Energy = Mass times the Speed of Light squared". This is the source of the Sun's energy.
NuSTAR
A hard X-ray mission designed to be sensitive to X-rays with higher energies than Chandra or XMM-Newton can study. It was launched in June 2012.
O
OAO 3
Orbiting Astronomical Observatory 3 - NASA ultraviolet/X-ray mission, also known as Copernicus.

 Tell me more aboutOAO 3.

occultation
The blockage of light by the intervention of another object; a planet can occult (block) the light from a distant star.
opacity
A property of matter that prevents light from passing through it. The opacity or opaqueness of something depends on the frequency of the light. For instance, the atmosphere of Venus is transparent to ultraviolet light, but is opaque to visible light.
orbit
The path of an object that is moving around a second object or point.
OSO 3
Orbiting Solar Observatory 3

 Tell me more about OSO 3

OSO 8
How Do We Weigh Planets? | NASA Space Place – NASA Science for Kids
How Do We Weigh Planets? | NASA Space Place – NASA Science for Kids

planets-weight

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Earth
Sun
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Educators

How Do We Weigh Planets?

The Short Answer:

	To weigh a planet, scientists need to know two things: how long it takes objects to orbit the planet and how far away those objects are from the planet. The time it takes an object to orbit a planet depends on its distance from the planet and the planet’s weight.
	

In real life, we can’t pick up a planet and put it on a scale. However, scientists do have ways to figure out how much a planet weighs. They can calculate how hard the planet pulls on other things. The heavier the planet, the stronger it tugs on nearby objects—like moons or visiting spacecraft. That tug is what we call gravitational pull.

What does gravity have to do with weight?

Earth's gravitational pull is what keeps the Moon in orbit around our planet. Voyager 1 snapped this picture of Earth and the Moon from a distance of 7.25 million miles. Credit: NASA/JPL-Caltech

When you stand on a scale, what it’s actually doing is measuring how hard Earth’s gravity is pulling on you.
If you were to step onto a scale on another planet, it would say something different than it does here. That’s because the planets weigh different amounts, and therefore the force of gravity is different from planet to planet.
For example, if you weigh 100 pounds on Earth, you would weigh only 38 pounds on Mercury. That’s because Mercury weighs less than Earth, and therefore its gravity would pull less on your body. If, on the other hand, you were on heavy Jupiter, you would weigh a whopping 253 pounds!
How do scientists use gravitational pull as a scale?
In order to figure out how heavy a planet is, scientists need to know two things: how long it takes nearby objects to orbit the planet and how far away those objects are from the planet. For example, the closer a moon is to its planet, the stronger the planet will tug on it.
NASA's Hubble Finds that Aging Brown Dwarfs Grow Lonely - NASA Science
Because brown dwarfs are so light, the gravitational hold tying wide binary pairs is very weak, and bypassing stars can easily tear these binaries apart," said Fontanive.The team selected a sample of brown dwarfs previously identified by NASA's Wide-Field Infrared Survey Explorer. It sampled some of the coldest and lowest-mass old brown dwarfs in the solar neighborhood. These old brown dwarfs are so cool (a few hundred degrees warmer than Jupiter in most cases) that their atmospheres contain water vapor that condensed out.To find the coolest companions, the team used two different near-infrared filters, one in which cold brown dwarfs are bright, and another covering specific wavelengths where they appear very faint due to water absorption in their atmospheres.  "This is the best observational evidence to date that brown dwarf pairs drift apart over time," said Fontanive. "We could not have done this kind of survey and confirmed earlier models without Hubble's sharp vision and sensitivity."The Hubble Space Telescope has been operating for over three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. Goddard also conducts mission operations with Lockheed Martin Space based in Denver, Colorado.