More to click Top 10 Facts About Space Shuttles! Making the station pay Drama and Learn Series. Back to top. The calculations of the expected speed using the results of new 3-D models give notably poorer agreement with the observed speeds than do earlier, simpler models. Moreover, the depth of the convection zone calculated under the new abundances is less than that found from the oscillations. Either the models need improving, or the solar oscillation folks have some work to do.
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All the naturally occurring elements came into being thanks to cosmic processes, whether Big Bang nucleosynthesis, stellar fusion, giant star evolution, or supernova nucleosynthesis. In fact, many of the heavier elements come almost exclusively from supernovae. The earliest stars created new, heavier elements than simple hydrogen and helium in their cores, and when they exploded as supernovae they scattered these materials out into the cosmos, as in the case of Cassiopeia A.
The color, energy, and wavelength distance between wave crests of light are all related. Yellow light, for instance, has a shorter wavelength than red light, so it is more energetic.
Convection cells dot the surface of the Sun, giving it a granulated appearance. Each cell, about the size of Texas, has its own cycle of heat and energy transport; the brighter centers are hot gases rising from below, and the darker edges are cooler gases falling back down. It's about miles thick, with temperatures reaching about 10, degrees Fahrenheit 5, degrees Celsius.
That's much cooler than the blazing core, but it's still hot enough to make carbon — like diamonds and graphite — not just melt, but boil. Most of the Sun's radiation escapes outward from the photosphere into space.
Above the photosphere is the chromosphere, the transition zone, and the corona. Not all scientists refer to the transition zone as its own region — it is simply the thin layer where the chromosphere rapidly heats and becomes the corona.
Visible light from these top regions of the Sun is usually too weak to be seen against the brighter photosphere, but during total solar eclipses, when the Moon covers the photosphere, the chromosphere looks like a fine, red rim around the Sun, while the corona forms a beautiful white crown "corona" means crown in Latin and Spanish with plasma streamers narrowing outward, forming shapes that look like flower petals.
Imagine walking away from a bonfire only to get warmer. The source of coronal heating is a major unsolved puzzle in the study of the Sun. The Sun generates magnetic fields that extend out into space to form the interplanetary magnetic field — the magnetic field that pervades our solar system. The field is carried through the solar system by the solar wind — a stream of electrically charged gas blowing outward from the Sun in all directions. Since the Sun rotates, the magnetic field spins out into a large rotating spiral, known as the Parker spiral.
This spiral has a shape something like the pattern of water from a rotating garden sprinkler. The Sun doesn't behave the same way all the time. It goes through phases of high and low activity, which make up the solar cycle. During this cycle, the Sun's photosphere, chromosphere, and corona change from quiet and calm to violently active.
Sunspots, eruptions called solar flares, and coronal mass ejections are common at solar maximum. Solar activity can release huge amounts of energy and particles, some of which impact us here on Earth.
It also can cripple power grids , and corrode pipelines that carry oil and gas. The strongest geomagnetic storm on record is the Carrington Event , named for British astronomer Richard Carrington who observed the Sept. Telegraph systems worldwide went haywire. Spark discharges shocked telegraph operators and set their telegraph paper on fire. Reportedly, the auroras were so brilliant that newspapers could be read as easily as in daylight.
The flare also caused power surges that melted power transformers in New Jersey. In December , X-rays from a solar storm disrupted satellite-to-ground communications and Global Positioning System GPS navigation signals for about 10 minutes.
Our Sun. The outer layers of the sun will expand from this extra energy. The sun will expand to about times its current radius, swallowing Mercury and Venus. As the sun expands, it will spread its energy over a larger surface area, which has an overall cooling effect on the star. When it reaches this temperature, helium will begin fusing to create carbon, a much heavier element.
This will cause intense solar wind and other solar activity, which will eventually throw off the entire outer layers of the sun. The red giant phase will be over. Temperatures in the core exceed The core is the only place where nuclear fusion reactions can happen. Protons of hydrogen atoms violently collide and fuse, or join together, to create a helium atom. This process, known as a PP proton-proton chain reaction, emits an enormous amount of energy.
The energy released during one second of solar fusion is far greater than that released in the explosion of hundreds of thousands of hydrogen bombs. During nuclear fusion in the core, two types of energy are released: photons and neutrinos. These particles carry and emit the light, heat, and energy of the sun. Photons are the smallest particle of light and other forms of electromagnetic radiation. The sun emits both photons and neutrinos in all directions, all the time.
Radiative Zone The radiative zone of the sun starts at about 25 percent of the radius, and extends to about 70 percent of the radius.
In this broad zone, heat from the core cools dramatically, from between seven million K to two million K. In the radiative zone, energy is transferred by a process called thermal radiation.
During this process, photons that were released in the core travel a short distance, are absorbed by a nearby ion, released by that ion, and absorbed again by another. One photon can continue this process for almost , years! Transition Zone : Tachocline Between the radiative zone and the next layer, the convective zone, there is a transition zone called the tachocline. Differential rotation happens when different parts of an object rotate at different velocities.
The sun is made up of gases undergoing different processes at different layers and different latitudes. The rotation rate of the sun changes rapidly in the tachocline. Instead, it transfers heat by thermal convection through thermal columns. When the gases reach the outer limits of the convective zone, they cool down, and plunge back to the base of the convective zone, to be heated again. Photosphere The photosphere is the bright yellow, visible "surface" of the sun.
The thermal columns of the convection zone are visible in the photosphere, bubbling like boiling oatmeal. Through powerful telescopes, the tops of the columns appear as granules crowded across the sun. Each granule has a bright center, which is the hot gas rising through a thermal column. Although the tops of the thermal columns look like small granules, they are usually more than 1, kilometers miles across.
Most thermal columns exist for about eight to 20 minutes before they dissolve and form new columns. Sunspots, solar flares, and solar prominences take form in the photosphere, although they are the result of processes and disruptions in other layers of the sun. Photosphere: Sunspots A sunspot is just what it sounds like—a dark spot on the sun. A sunspot forms when intense magnetic activity in the convective zone ruptures a thermal column.
At the top of the ruptured column visible in the photosphere , temperature is temporarily decreased because hot gases are not reaching it. Solar matter surges out of this opening in formations called solar flares. These explosions are massive: In the period of a few minutes, solar flares release the equivalent of about billion megatons of TNT, or about a sixth of the total energy the sun releases in one second.
Clouds of ions, atoms, and electrons erupt from solar flares, and reach Earth in about two days. CMEs typically form near the active regions of sunspots, the correlation between the two has not been proven. The cause of CMEs is still being studied, and it is hypothesized that disruptions in either the photosphere or corona lead to these violent solar explosions. Photosphere: Solar Prominence Solar prominences are bright loops of solar matter.
They can burst far into the coronal layer of the sun, expanding hundreds of kilometers per second. These curved and twisted features can reach hundreds of thousands of kilometers in height and width, and last anywhere from a few days to a few months. Solar prominences are cooler than the corona, and they appear as darker strands against the sun.
For this reason, they are also known as filaments. Photosphere: Solar Cycle The sun does not constantly emit sunspots and solar ejecta; it goes through a cycle of about 11 years.
During this solar cycle, the frequency of solar flares changes.
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