The Sun is an almost perfectly symmetric yellow dwarf star [spectral class G2V] which is at the center of our Solar System.

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Thermal contact burn

My client fell asleep in a bus stop leaning back against 3/16 in clear plate glass For an hour with a tee shirt on. It was about 80 degrees Fahrenheit and the sun was shinning on the glass. He woke up ...
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102 views

Are the electrons at the centre of the Sun degenerate or not?

Trying to find an answer to this question, I came across two different methods of determining whether electrons at the center of the sun are degenerate or not. The first method, used here, calculates ...
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2answers
122 views

Can the Sun's core be treated as an ideal gas?

I know that a gas behaves more like an ideal gas at higher temperature, and that is very well achieved in the Sun's core. But also low pressure is needed for a gas to behave like an ideal gas, and the ...
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2answers
31 views

Is it possible to calculate the relative abundances of elements in the sun based on its line spectrum using a common lab spectroscope?

There are many problems that I feel would hinder the process: atmospheric noise, light pollution etc. Let's assume that I bypass these problems and get an accurate emission line spectrum on the ...
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1answer
76 views

How do solar cells increase the lifespan of the Sun?

While reading "Physics of Solar Cells" by Würfel, I came across an amusing statement: An interesting aspect arises if we had to pay for solar energy, but could also get a refund for energy ...
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63 views

Calculating the Surface Temperature of the Sun with a Metallic Strip from the Surface of Earth

I am trying to calculate the surface temperature of the sun with a copper strip. I have a temperature sensor to calculate the temperature of the strip and that's it. Assuming the rate at which energy ...
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3answers
791 views

How does the heat of Sun come on Earth when there is no medium?

Sun is the most important source for life on Earth which gives sunlight and heat on Earth. But I was wondering like how does the heat of Sun come on Earth when there is no medium out there in space?
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3answers
58 views

Is sunlight truly white?

I recently purchased a book on nuclear astrophysics, with no goal of mastering the topic but merely to read in between exams and hopefully learn something, it is revealed that the sun is composed ...
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1answer
42 views

How close to the surface of the Sun would one have to be to determine an 'upright' position relative to it's surface?

As we stand upon the surface of the earth we're able to establish a relative 'up' and 'down' direction due to gravitational forces. As we leave the confines of the earths gravitational attraction ...
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1k views

Is the Earth the center of the Solar System? [duplicate]

Alright guys, so I attracted you with the title. Now, to preface the question, I am fully aware of the work of Copernicus, as well as the concepts of Heliocentrism and Barycentric Coordinates. I have ...
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23 views

Does sun's geographical(not magnetic) polarity changes?

What i am asking is, do sun's north pole & south pole reverses, resulting rotation change?
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1answer
49 views

Is sunlight like a spotlight? [closed]

It is believed that if earth would have no atmosphere then the sunlight would fall on earth like a spot light. According to this fact the sunlight on moon must fall like a spot light. Does it? Then ...
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3answers
429 views

How hot can metal get in sunlight? [closed]

I will make some 5mm blackened steel letters for a building. Now, in the sunlight in summer, how hot can they get? EDIT: i want to place some LEDs on the back of the letters. now the question is if ...
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1answer
18 views

What causes the twisting of flux loops, leading to coronal mass ejections?

I understand that the loop twisting is the ultimate originator of the CMEs but what causes this twisting? The expansion of the loops is caused by a magnetic pressure differential between the top and ...
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0answers
17 views

What is a magnetic flux rope and how does it differ from magnetic flux tubes?

I am currently taking a course on solar physics and it appears the terminology in solar physics is either needlessly verbose or I am just missing something. What is a flux rope and what is a flux ...
3
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1answer
49 views

Solar Power Fusion

Would it be possible through a clever arrangement of solar dishes, lenses and mirrors etc, to create fusion at the focal point? Imagine you arrange your solar dishes, lenses and mirrors in such a ...
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1answer
24 views

What causes the black shimmering bands on a sun-lit surface?

I can't figure it out. I thought it was the window causing it, but even without it it happened. It seems to be the motion of the air that causes it, but why shimmering black bands? Sometimes this ...
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2answers
264 views

How does the sun's surface conduct thermal energy from the convective zone to the corona?

How does the surface of the photosphere conduct thermal energy from the convective zone to the corona, while remaining at such a relatively low temperature itself? It seems odd to me that the ...
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2answers
125 views

What would happen to a star if a Dyson sphere lined with mirrors reflected a significant portion of the stars light back to the star

I have looked for similar questions here on stack exchange. The closest example to this that I found is Could a Dyson sphere destroy a star. That question assumed less than perfect absorption of ...
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1answer
73 views

Why does the sky look blue rather than violet? [duplicate]

Sky looks blue because because our eyes are sensitive to blue colour. But when viewed through a camera why don't we see violet of the sky even though we can see violet colour of other pictures taken ...
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3answers
80 views

What will be the gravitational pull of the Sun if the Sun contracts to a black hole?

What will be the gravitational pull of the Sun if the Sun contracts to a black hole, and would the Sun be a Schwarzschild black hole or not?
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0answers
57 views

Do solar panels work forever?

Do solar panels generate electricity infinitely? IF YES then how do the electrons in the n-type which go to p-type then how do those electrons restore themselves. I mean in n-type terminal we have the ...
3
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1answer
98 views

Force and lions

Alright. So me and some other people right now need an answer to this. If you have 1 trillion lions traveling at 81 kilometers (top speed of a lion) towards the Sun in a pretty dense ball. (As dense a ...
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1answer
52 views

Have scientists always known that the Sun was not a fuel+air system?

Astronomy is far older than nuclear physics. So there was a long time in which fire was a reasonable explanation for the sun burning. Has any scientist figured out the sun cannot possibly be a normal ...
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2answers
113 views

Why doesn't the Sun appear green to our eyes?

The spectrum of the Sun as seen at sea level can be seen at https://commons.wikimedia.org/wiki/File:Solar_Spectrum.png so we can see that wavelengths around green to yellow are the ones that are the ...
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23 views

Inclination of planets

What is the inclination of each planet with the equator of the Sun? Doesn't this have a relationship with the eccentricity of the planet's orbit?
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Can the Sun capture dark matter gravitationally?

I think my title sums it up. Given that we think the dark matter is pseudo-spherically distributed and orbits in the Galactic potential with everything else, then I assume that its speed with respect ...
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2answers
152 views

Are we feeling the sun's heat?

If I may summarize something I told a friend in a pub... "We don't get heat from the sun at all. Heat requires matter to move through and there's too much vacuum between the sun and us for any heat ...
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36 views

Explanation for strange atmospheric phenomenon

OK, I've seen this strange thing in the sky sometimes. Not all that often, but sometimes. It actually happened tonight. On most nights, at say 9 P.M. it is dark. There might be stars, moon, ...
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2answers
92 views

Which will collide first, the moon and Earth, or Sun and Earth?

As time progresses, which scenario will happen first? The moon colliding with Earth, or the Earth colliding with the Sun? I figure the Moon and Earth will happen first, based on proximity, but the sun ...
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1answer
185 views

How much lux does the sun emit?

I want to know how much lux the sun emits on a bright day - I don't mean when one stares directly at the sun, but rather when one walks casually outside when the sun is shinning brightly. Now the ...
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0answers
12 views

Are there any particles emitted by the sun that can be observed in a Wilson cloud chamber?

Are there any particles emitted by the sun that can be observed in a Wilson cloud chamber? Are there better hours of the day/time of the year to see them? More generally, is there a list of cosmic ...
4
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1answer
62 views

Desynchronised pixels in images of the Sun?

NASA published this wonderfull video of Sun from SDO: https://www.youtube.com/watch?v=GSVv40M2aks And it occurred interesting question: Sun is very big sphere. Its so big that it took light 4,6 ...
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1answer
76 views

What is the total matter equivalent of the Sun's output per year?

Say we can collect all the energy from the sun's output and all the particles from the solar wind. If we had an energy to mass converter and turned everything into say, carbon, how many kilograms of ...
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54 views

Solar plants and energy conservation

I'd like to apologise if this question is stupid or if it was asked ten thousand times - I haven't found an answer to it. Quite possibly due to mediocre English or abominable knowledge of physics. ...
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2answers
172 views

Does the sun have a black hole inside of it?

The Schwarzschild radius of the sun is approx. 3 km. It would be a black hole if all the mass of it were within the 3km. However, even with the mass spread out couldn't the sun technically have a or ...
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5answers
693 views

What makes Sun's light travel as parallel beams towards earth?

Sun's light appear to travel as parallel beams towards earth $_1$. Sun produces electromagnetic radiations through pp chain and other reactions in Photosphere $_2$. I don't see whether these ...
108
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2answers
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Why do sunbeams diverge even though the sun is much more than a few kilometers away?

Consider this picture of sun beams streaming onto the valley through the clouds. Given that the valley is only (at a guess) 3km wide, with simple trigonometry and the angles of the beams, this ...
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5answers
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Why does heat lose its energy as we get further away?

Why does heat lose its energy dramatically as I move back? Say I have a fire around 0.5 meters in front of me, I can clearly feel the heat, however, as I move even very slightly back, say 1 meter ...
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1answer
86 views

Nuclear fusion - Hydrogen isotopes

What is the isotope composition of hydrogen atoms in the sun? Are the ratios of protium:deuterium:tritium similar to those we find on earth? What does the nuclear fusion of hydrogen atoms in the sun ...
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1answer
107 views

What does a sample of the Sun look like? Does it look like fire or gas?

Suppose that in the future a highly resistant spacecraft went to the Sun and collected three samples of the Sun: one from its surface, one from its core, and one midway. The three samples were put ...
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2answers
164 views

Solar spectrum units

Why is intensity $I$ on a graph of the solar spectrum always showed in units of $[\mathrm{W/m^2/nm}]$ instead of simply $[\mathrm{W/m^2}]$? (The y-axis on the graph.) It is apparently shown as ...
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1answer
76 views

Temperature of the surface of the sun? [closed]

I recently had an exam question that asked for the temperature at the surface of the sun. The question is The equation I believe you have to use is The Q/t is the radiant power produced by the ...
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30 views

Different ways of converting solar energy to other forms of energy

Okay so after receiving our Physics papers today I decided to tell the teacher why I lost marks on the last question: "Mention the energy conversions undergone here Sun --> Coal-fired boiler --> ...
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8answers
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Why does the Sun always rise in the East?

Why does the Sun always rise in the East? Earth is rotating on its own axis & also revolves around the Sun, then how come the Sun always rises in the East?
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3answers
305 views

Why can we see white objects as white under the sun if the sunlight is yellow?

I get that the sun is producing white light which is scattered threw our atmosphere so that the light of the sun reaching our eyes is yellow. So how come if I look to a piece of white paper under ...
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2answers
140 views

Why does a photon take less than a week to come out of the convection zone of the sun?

Sun consists of three parts: Radiation zone, Convection zone, Photosphere . When photon is formed at the core, it has high energy equivalent to $\gamma$ ray. When it crosses the radiation zone, it ...
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1answer
202 views

Calculating the Sun's emitted power in a wavelength range?

Is there an equation that describes the Sun's emitted power on the surface [in $\frac{W}{m^2}$] over a selected wavelength range (from $\lambda_1$ to $\lambda_2$) ? I am guessing this can be ...
3
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1answer
129 views

What would a normal thermometer read at the Sun's photosphere?

I was reading about the Earth's Thermosphere, and I quote this: "The highly diluted gas in this layer can reach 2,500 °C (4,530 °F) during the day. Even though the temperature is so high, one would ...
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51 views

Would a giant satellite laser work as a weapon?

If someone built a satellite to float about in space, which used mirrors to focus and magnify energy from the sun directly into one direct spot (like in the James Bond film Die Another Day) would it ...