One of the reasons for this is because the Earth lies within our sun 's Habitable Zone aka. This means that it is in right spot neither too close nor too far to receive the sun's abundant energy , which includes the light and heat that is essential for chemical reactions. But how exactly does our sun go about producing this energy? What steps are involved, and how does it get to us here on planet Earth? The simple answer is that the sun, like all stars, is able to create energy because it is essentially a massive fusion reaction.
Scientists believe that this began when a huge cloud of gas and particles i. This not only created the big ball of light at the center of our solar system, it also triggered a process whereby hydrogen, collected in the center, began fusing to create solar energy. Technically known as nuclear fusion, this process releases an incredible amount of energy in the form of light and heat. But getting that energy from the center of our sun all the way out to planet Earth and beyond involves a couple of crucial steps.
- Wittgenstein (Blackwell Great Minds);
- Structure of the Solar Chromosphere.
- Layers Of The Sun: Important And Unique Facts;
- Holy Things: A Liturgical Theology!
- Gluck: Her Biography.
In the end, it all comes down to the sun's layers, and the role each of them plays in making sure that solar energy gets to where it can help create and sustain life. It is here, in the core, where energy is produced by hydrogen atoms H being converted into nuclei of helium He. This is possible thanks to the extreme pressure and temperature that exists within the core, which are estimated to be the equivalent of billion atmospheres The net result is the fusion of four protons hydrogen nuclei into one alpha particle — two protons and two neutrons bound together into a particle that is identical to a helium nucleus.
Two positrons are released from this process, as well as two neutrinos which changes two of the protons into neutrons , and energy. The core is the only part of the sun that produces an appreciable amount of heat through fusion. The rest of the sun is heated by the energy that is transferred from the core through the successive layers, eventually reaching the solar photosphere and escaping into space as sunlight or the kinetic energy of particles.
Astronomy Lecture Number 14
The sun releases energy at a mass—energy conversion rate of 4. To put that in perspective, this is the equivalent of about 9. This is the zone immediately next to the core, which extends out to about 0. There is no thermal convection in this layer, but solar material in this layer is hot and dense enough that thermal radiation is all that is needed to transfer the intense heat generated in the core outward. Basically, this involves ions of hydrogen and helium emitting photons that travel a short distance before being reabsorbed by other ions.
Temperatures drop in this layer, going from approximately 7 million kelvin closer to the core to 2 million at the boundary with the convective zone. Density also drops in this layer a hundredfold from 0. Here, the temperature is lower than in the radiative zone and heavier atoms are not fully ionized. As a result, radiative heat transport is less effective, and the density of the plasma is low enough to allow convective currents to develop.
Because of this, rising thermal cells carry the majority of the heat outward to the sun's photosphere. Once these cells rise to just below the photospheric surface, their material cools, causing their density increases. This forces them to sink to the base of the convection zone again — where they pick up more heat and the convective cycle continues. At the surface of the sun, the temperature drops to about 5, K. The turbulent convection of this layer of the sun is also what causes an effect that produces magnetic north and south poles all over the surface of the sun.
It is also on this layer that sunspots occur, which appear as dark patches compared to the surrounding region.
These spots correspond to concentrations in the magnetic flux field that inhibit convection and cause regions on the surface to drop in temperature to compared to the surrounding material. Lastly, there is the photosphere, the visible surface of the sun.
It is here that the sunlight and heat that are radiated and convected to the surface propagate out into space. Because the upper part of the photosphere is cooler than the lower part, an image of the sun appears brighter in the center than on the edge or limb of the solar disk, in a phenomenon known as limb darkening. The photosphere is tens to hundreds of kilometers thick, and is also the region of the sun where it becomes opaque to visible light.
The reasons for this is because of the decreasing amount of negatively charged Hydrogen ions H— , which absorb visible light easily. Skip to main content.
Utah Astronomy Resources
Subscribe Search My Account Login. Abstract THE suggestion of Biermann 1 and Schwarzschild 2 , that the radially increasing temperature of the solar atmosphere is to be ascribed to propagation of non-thermal energy, such as acoustic waves, is now generally accepted. Rent or Buy article Get time limited or full article access on ReadCube. References 1 Biermann, L. Google Scholar 7 Lindsey, R.
FRESH INSIGHTS ON THE STRUCTURE OF THE SOLAR CORE
Google Scholar 8 Ref. Rights and permissions Reprints and Permissions. Further reading Report on the solar physics-plasma physics workshop P. Sturrock , P. Baum , J. Beckers , C.
Newman , E. Priest , H. Rosenberg , D. The chromosphere is about km thick. We only see this layer and the other outer layers during an eclipse.
The Structure and Composition of the Sun
The corona extends outwards for more than a solar radius. Surface temperature of the Sun is the temperature in photosphere - K. Main Q: How can a Spherical Ball of Gas radiate energy over long period of time remaining visibly unchanged?