vania-janet/multiturn-rag-retrieval-data huggingface dataset:
How do planets form? – Exoplanet Exploration: Planets Beyond our Solar System
Gravity and other forces cause material within the disk to collide. If the collision is gentle enough, the material fuses, growing like rolling snowballs. Over time, dust particles combine to form pebbles, which evolve into mile-sized rocks. As these planetesimals orbit their star, they clear material from their path, leaving tracks of space empty but for fine dust. At the same time, the star gobbles up nearby gas and pushes more distant material farther away. After billions of years, the disk will have totally transformed, much of it now in the form of new worlds. Watch the video to see this process unfold.

Where the disk is colder, far enough from the star that water can freeze, tiny fragments of ice hitch a ride with dust. Dirty snowballs can amass into giant planetary cores. These colder regions also allow gas molecules to slow down enough to be drawn onto a planet. This is how Jupiter, Saturn, Uranus and Neptune, the gas giants of our solar system, are thought to have formed. Jupiter and Saturn are thought to have formed first and quickly within the first 10 million years of the solar system.
In the warmer parts of the disk, closer to the star, rocky planets begin to form. After the icy giants form there’s not a lot of gas left for the terrestrial planets to accrete. Planets that are rocky like Mercury, Venus, Earth and Mars may take tens of millions of years to form after the birth of the star. The details of exactly where planets prefer to form in disks is still a mystery and an ongoing area of research.
Once planets form around a star they are referred to as planetary systems, which are defined as sets of gravitationally bound objects that orbit a star. They can consist of one or more planets, but may also include dwarf planets, asteroids, natural satellites, meteoroids, and comets. The Sun and its planets, including Earth, is known as the solar system. The term "extrasolar" system and "exoplanet" system refer to planetary systems other than our own.

Life and Death of a Planetary System

How did we get here? How do stars and planets come into being?
Facts About Earth - NASA Science
That means 30 Earth-sized planets could fit in between Earth and its Moon.RingsEarth has no rings.FormationWhen the solar system settled into its current layout about 4.5 billion years ago, Earth formed when gravity pulled swirling gas and dust in to become the third planet from the Sun. Like its fellow terrestrial planets, Earth has a central core, a rocky mantle, and a solid crust.StructureEarth is composed of four main layers, starting with an inner core at the planet's center, enveloped by the outer core, mantle, and crust.The inner core is a solid sphere made of iron and nickel metals about 759 miles (1,221 kilometers) in radius. There the temperature is as high as 9,800 degrees Fahrenheit (5,400 degrees Celsius). Surrounding the inner core is the outer core. This layer is about 1,400 miles (2,300 kilometers) thick, made of iron and nickel fluids.In between the outer core and crust is the mantle, the thickest layer. This hot, viscous mixture of molten rock is about 1,800 miles (2,900 kilometers) thick and has the consistency of caramel. The outermost layer, Earth's crust, goes about 19 miles (30 kilometers) deep on average on land. At the bottom of the ocean, the crust is thinner and extends about 3 miles (5 kilometers) from the seafloor to the top of the mantle.SurfaceLike Mars and Venus, Earth has volcanoes, mountains, and valleys. Earth's lithosphere, which includes the crust (both continental and oceanic) and the upper mantle, is divided into huge plates that are constantly moving. For example, the North American plate moves west over the Pacific Ocean basin, roughly at a rate equal to the growth of our fingernails. Earthquakes result when plates grind past one another, ride up over one another, collide to make mountains, or split and separate.Earth's global ocean, which covers nearly 70% of the planet's surface, has an average depth of about 2.5 miles (4 kilometers) and contains 97% of Earth's water. Almost all of Earth's volcanoes are hidden under these oceans.
How Did the Solar System Form? | NASA Space Place – NASA Science for Kids
How Did the Solar System Form? | NASA Space Place – NASA Science for Kids

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How Did the Solar System Form?

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The solar system is a pretty busy place. It’s got all kinds of planets, moons, asteroids, and comets zipping around our Sun.
But how did this busy stellar neighborhood come to be?
Our story starts about 4.6 billion years ago, with a wispy cloud of stellar dust.
This cloud was part of a bigger cloud called a nebula.
At some point, the cloud collapsed—possibly because the shockwave of a nearby exploding star caused it to compress.
When it collapsed, it fell in on itself, creating a disk of material surrounding it.
Finally the pressure caused by the material was so great that hydrogen atoms began to fuse into helium, releasing a tremendous amount of energy. Our Sun was born!
Even though the Sun gobbled up more than 99% of all the stuff in this disk, there was still some material left over.
Bits of this material clumped together because of gravity. Big objects collided with bigger objects, forming still bigger objects. Finally some of these objects became big enough to be spheres—these spheres became planets and dwarf planets.
Rocky planets, like Earth, formed near the Sun, because icy and gaseous material couldn’t survive close to all that heat.
Gas and icy stuff collected further away, creating the gas and ice giants.
And like that, the solar system as we know it today was formed.
There are still leftover remains of the early days though.
Asteroids in the asteroid belt are the bits and pieces of the early solar system that could never quite form a planet.
Way off in the outer reaches of the solar system are comets.
Transit of Venus, Sun-Earth Days 2013
During a severe solar storm, Earth loses about 100 tons of its atmosphere into space.
Toy 'rare-earth' magnets can be 5 times stronger than a sunspot magnetic field.

Magnetism Facts

All magnetic fields are produced by moving or spinning charged particles...somewhere
Lines of magnetic force do not actually exist.
Magnetic poles always come in pairs.
The strongest magnetic field in nature is from the magnetar star SGR 1806-20, which has been estimated as 800 trillion Gauss.
A typical galaxy like the Milky Way has a magnetic field strength of about 0.000003 Gauss.
A refrigerator magnet has a strength of 100 Gauss.
A sunspot can have a magnetic field with a strength up to 10,000 Gauss, but they live very short lives!
Most magnetic storms on Earth happen during the Equinoxes in March and September
The sun's magnetic poles flip their location on the sun every 22 years, called the Hale Magnetic Cycle.
Earth's magnetic poles reverse their geographic locations every 300,000 years. The last event happened 780,000 years ago.
Magnetic pole 'reversals' have no effect on the rotational poles of a star or planet.
The geographic location of Earth's North Magnetic Pole is currently moving nearly due-North at a speed of 100 meters per day.
Earth's magnetic field is declining in strength by 5% every century.
Depending on your rate and direction of motion, a pure magnetic field can be turned into an electric field and vice versa.
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.

 
 
 

 
 
 
 

 


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Earth - NASA Science
Therefore, NASA remains steadfast in leading the way in oceanic research.Images of the DayMore Earth Observatory Images of the DayAntarctic Ice Shelf Spawns Iceberg A-83The Brunt Ice Shelf lost a large wedge of floating ice, the third sizeable iceberg to calve from the shelf in recent years.Read MoreDerecho Darkens HoustonDestructive winds left many people in the most populous city in Texas without power.Read MoreWhite and Black Volcanoes of Saudi ArabiaContrasting colors of lava and ash reveal the geologic origins of Harrat Khaybar’s volcanic cones.Read MoreDusty Spring in the Tarim BasinStrong winds kicked up sand and dust from China’s vast Taklimakan Desert.Read MoreOrce’s Archaeological WonderlandAncient hominin fossils lie beneath the sandy soils on the outskirts of this village in southern Spain. Read MoreFarming on Fertile Land in FranceFarmers grow a variety of crops along river floodplains near Lyon.Read MoreMontgomery Reef RevealedLarge tidal swings expose a plateau-shaped reef around Australia’s Yawajaba island at low tide.  Read MoreExplore EarthAir QualityAir pollution is a significant threat to human health and our environment. Instruments on NASA satellites, along with airborne and ground-based sensors, are constantly collecting data on major pollutants in our atmosphere.Learn MoreNASA has a unique vantage point for observing the beauty and wonder of Earth and for making sense of it. Looking back from space, astronaut Edgar Mitchell once called Earth “a sparkling blue and white jewel,” and it does dazzle the eye.Earth: a photo-essay.Earth Information CenterFor more than 50 years, NASA satellites have provided data on Earth's land, water, air, temperature, and climate.
How Did the Solar System Form? | NASA Space Place – NASA Science for Kids
Rocky planets, like Earth, formed near the Sun, because icy and gaseous material couldn’t survive close to all that heat.
Gas and icy stuff collected further away, creating the gas and ice giants.
And like that, the solar system as we know it today was formed.
There are still leftover remains of the early days though.
Asteroids in the asteroid belt are the bits and pieces of the early solar system that could never quite form a planet.
Way off in the outer reaches of the solar system are comets. These icy bits haven’t changed much at all since the solar systems formation.
In fact, it is the study of asteroids and comets that allows scientists to piece together this whole long story.

 	article last updated August 29, 2022
 

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Sun-Earth Days 2013: Articles
The sun is a moderate sized (1,400,000 km in diameter), G spectral type, variable star in a vast collection of an estimated 200-400 billion stars in a barred spiral galaxy called the Milky Way. Though it is a smallish star, most stars in our galaxy are smaller, and less massive. Our sun is, like most stars in our galaxy and probably most stars, a main sequence star which means it generates its energy by thermonuclear fusion resulting in the release of gamma ray photons during a process in the core where hydrogen nuclei (protons) are fused together to form helium nuclei. This process, converting hydrogen to helium, driven by the enormous internal pressure of the sun's mass (2x1030 kg or over 300,000 times the mass of the Earth!) is what makes a star a star. Since everything forms from a roughly basic and somewhat consistent cosmic menu of elements (75% H, 24% He,...) the variable that determines whether you get an asteroid, a planet, or a star is mass. Enough mass creates enough pressure to start this fusion process and create a star. Not enough mass and you have a failed star or planet (even less mass and you get an object that is not round at all). It's that simple. The sun formed around the same time that the planets formed, from a molecular cloud - remnant of a super nova explosion. The sun is very old, by human standards but only middle aged by stellar standards, about 4.6 billion years old and it should be around in a more or less similar form for maybe another 5 billion years.
It might be interesting to note that considering only classical (or Newtonian) physics, the physics that you learned in high school, the physics that defined reality for around 400 years, since Isaac Newton gave his three laws of motion, the sun and all the stars cannot shine. Classical physics does not allow two similarly charged protons to bond. In addition, matter - energy equivalency (E=mc2) was not known until the early 1900's. So before Einstein and before quantum physics, there was no plausible explanation for how the sun generated its energy. Want to know more? Read "On the age of mostly everything".
What Causes the Seasons? | NASA Space Place – NASA Science for Kids
Earth has seasons because its axis doesn't stand up straight. 
But what caused Earth to tilt?

Long, long ago, when Earth was young, it is thought that something big hit Earth and knocked it off-kilter. So instead of rotating with its axis straight up and down, it leans over a bit.
By the way, that big thing that hit Earth is called Theia. It also blasted a big hole in the surface. That big hit sent a huge amount of dust and rubble into orbit. Most scientists think that that rubble, in time, became our Moon.
As Earth orbits the Sun, its tilted axis always points in the same direction. So, throughout the year, different parts of Earth get the Sun’s direct rays.

Sometimes it is the North Pole tilting toward the Sun (around June) and sometimes it is the South Pole tilting toward the Sun (around December). 
It is summer in June in the Northern Hemisphere because the Sun's rays hit that part of Earth more directly than at any other time of the year. It is winter in December in the Northern Hemisphere, because that is when it is the South Pole's turn to be tilted toward the Sun.

Earth's lopsided orbit
Earth's perihelion (point closest to Sun) = 91,400,000 miles from Sun
Earth's aphelion (point farthest from Sun) = 94,500,000 miles from Sun
While that is a difference of over 3 million miles, relative to the entire distance, it isn’t much.

And, believe it or not, aphelion (when Earth is farthest from the Sun) occurs in July, and perihelion (when we are closest) occurs in January. 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
NASA - Sun-Earth Day 2010
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Magnetism Facts

All magnetic fields are produced by moving or spinning charged particles...somewhere
Lines of magnetic force do not actually exist.
Magnetic poles always come in pairs.
The strongest magnetic field in nature is from the magnetar star SGR 1806-20, which has been estimated as 800 trillion Gauss.
A typical galaxy like the Milky Way has a magnetic field strength of about 0.000003 Gauss.
A refrigerator magnet has a strength of 100 Gauss.
A sunspot can have a magnetic field with a strength up to 10,000 Gauss, but they live very short lives!
Most magnetic storms on Earth happen during the Equinoxes in March and September
The sun's magnetic poles flip their location on the sun every 22 years, called the Hale Magnetic Cycle.
Earth's magnetic poles reverse their geographic locations every 300,000 years. The last event happened 780,000 years ago.
Magnetic pole 'reversals' have no effect on the rotational poles of a star or planet.
The geographic location of Earth's North Magnetic Pole is currently moving nearly due-North at a speed of 100 meters per day.
Earth's magnetic field is declining in strength by 5% every century.
Depending on your rate and direction of motion, a pure magnetic field can be turned into an electric field and vice versa.
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!
Sun-Earth Days 2013: Articles
Now remembering Michael Faraday's discovery that moving charge generates a magnetic field, this is how the sun's magnetic field is generated - electromagnetic induction within a star. When this process operates within a star or planet, we call it a dynamo. Because the sun is composed of plasma and not solid material, its rotation rate is not constant. Therefor, the motion of ionized gas around the sun is not constant. The sun rotates slower at high latitudes (near the poles) than at the equator. This differential motion causes stretching and twisting of the sun's magnetic field creating a complex field that is the sun's magnetosphere. The complexity of the field increases from solar minimum to solar maximum, as lines of magnetic force are wound together and distorted. As field lines, generated deep within the sun emerge above the sun's surface or "photosphere", they create a strong local magnetic field that prevents deeper and hotter, convecting plasma from rising to the surface. The area around this field then appears cooler than the surrounding photosphere and so darker. These dark regions are called sunspots. Since magnets and so magnetic fields always have a north and a south pole, the highly magnetic sunspots often occur in pairs (e.g. north and south poles) and can be seen channeling hot plasma gases between them in structures called prominences.

Figure 9: Starspot cycle of 40 Eridani

This occurs because the electrically charged particles comprising the plasma are attracted to magnetic fields or lines of magnetic force and so are pulled along field lines from one pole to another. Other stars have sunspots too! We have both direct visual evidence of this as well as inferred evidence from periodic increases and decreases in a star's brightness. Other evidence includes Zeeman line splitting and Doppler imaging. Since sunspots require a magnetic field, differential rotation, and a convective stellar envelope, we can see visual evidence that other stars are similar to the sun. Massive stars have convective cores and radiative envelopes. This generally produces a weaker magnetic field and fewer sunspots.
What Is El Niño? | NASA Space Place – NASA Science for Kids
What Is El Niño? | NASA Space Place – NASA Science for Kids

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What Is El Niño?

The Short Answer:

	El Niño is a weather pattern. In El Niño years, ocean waters along South America and California warm above normal temperatures. Many rain clouds form over this warm part of the ocean and move inland, dumping more rain than usual in South and Central America and in the United States.
	

What is El Niño anyway?
El Niño is a condition that sometimes occurs in the Pacific Ocean, but it is so big that it affects weather all over the world.
Weather depends a lot on ocean temperatures. Where the ocean is warm, more clouds form, and more rain falls in that part of the world. In the Pacific Ocean, near the equator, the Sun makes the water especially warm on the surface.
Normally, strong winds along the equator push the warm surface water near South America westward toward Indonesia. When this happens, the cooler water underneath rises up toward the surface of the ocean near South America.

However, in the fall and winter of some years, these winds are much weaker than usual. They actually blow the other way (toward South America instead of Indonesia) in October. So the warm surface water along the equator piles up along the coast of South America and then moves north towards California and south toward Chile.
Many fish that live in the normally cooler waters off the coast of South America move away or die. The fishermen call this condition of warm coastal waters and poor fishing "El Niño" meaning "the Christ Child," because in the occasional years it comes, it comes at Christmas time.

In El Niño years, lots of rain clouds forms over this warm part of the ocean. These clouds move inland and dump much more rain than usual in South and Central America and in the United States. Meanwhile, other parts of the world can suffer drought. Weather patterns all over the world may be unusual, making lakes out of deserts and charcoal heaps out of rain forests.
Forces - NASA Science
Two negative or positive charges repel each other; one of each attracts.While electromagnetism is stronger than gravity, it is often balanced out in large objects by the equal numbers of positive and negative charges that form neutral atoms. For example, Earth has a magnetic field due to electric currents in its liquid core; however, Earth itself is electrically neutral.Strong Nuclear ForceNASANuclear forces affect our daily lives, but they work on distances smaller than atoms.The strong nuclear force, or strong force for short, holds together the building blocks of atoms. It always attracts and works at two different size scales in atoms. At the level of an atomic nucleus, the strong force holds together the protons and neutrons that form the essence of the elements. On an even smaller scale, the strong force holds together the oppositely charged quarks that make up the neutrons and protons themselves.As suggested by its name, the strong force is the strongest of the fundamental forces. It is about 100 times stronger than electromagnetism and 100 trillion trillion trillion times stronger than gravity.However, the strong force only has influence over very, very small distances. For anything larger than the nucleus of a medium-sized atom (about 100 million times smaller than the width of a human hair), its influence quickly drops, and other forces will be stronger.Weak Nuclear ForceNASAThe weak force is responsible for interactions between subatomic particles – the tiny particles that are the building blocks for matter, like protons, neutrons, and electrons.In particular, the weak force can change one quark type into another. Protons and neutrons are made of two quark varieties, up and down. 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.