Sun Definition and 1000 Threads

Hydrogen atoms are in ionised state in the Sun? So the electrons are in a separate gas state? If, yes, than what is the main properties of that gas: temperature, partial pressure, velocity distribution, etc. Can somebody give me a good reference or answers?

Hello, I would like to ask why if the Earth rotate around the Sun in circle orbit, it must have an kinetic energy equal to negative half of potential energy it has at anytime rotating round the sun, which Ek = -Ep/2 ! If this situation cannot be achieved, our Earth will move in a new ellipse...

Hello! could you help me with this? I´m from biology field and have some difficulties with the following calculation: I want to estimate how much mor UV is coming from a mercury short arc lamp of a fluorescence microscop compared with the sun UV, so that I use the right eye protection for...

Lets take this specific example: Sun is radiating heat and a water tank with a certain surface area S absorbs this heat. Sun rays are perpendicular to this tank. [PLAIN]http://pokit.etf.ba/get/778c2978a453178481d142a891ae07c5.jpg If I know much energy did my tank of water...

Homework Statement This is a past exam question that I am trying to get my head around but keep getting stuck Show that if a white dwarf were at the centre of the solar system instead of the sun, it would have an apparent visual brightness of -18.6mag. Assume that the white dwarf has surface...

Homework Statement [a] find the toal power radiated into space by the sun, assuming it to be a perfect emitter at T=5500 K. The Sun's radius is 7.0x10^8 m. [b] From this determine the power per unit area arriving at the earth, 1.5x10^11 m away. The Attempt at a SolutionHey guys! Sorry for...

Hi Folks, Does anyone have a good source of space pictures in particular pictures of our sun in a few billion years viewed from earth? I tried google, not many good ones. Thanks

Homework Statement If a scuba diver fills his lungs to full capasity of 5.5 L when 8.0 m below the surface, to what volume would his lungs expand if he quickly rose to the surface? Homework EquationsP=pg(H) The Attempt at a SolutionHeyguys! :) I know that P=pgh but I have volume...

Hello all, Does anybody have an idea why the solar spectrum, as measured above the Earth's atmosphere, has such bad agreement with the blackbody curve? I would think that any deviations such as sunspots would be averaged out because of the distance, and that in general (if any deviation)...

Homework Statement temp = 6000k what is the power radiated by the sun per megacycle bandwidth at a wavelength of 2cm? Radius of sun = 7 x 10 10 cmHomework Equations i was asked to use this equation energy density u = ω2kT dω / (π2c3) NOTE: π is pi. not n The Attempt at a Solution but how do...

One of the proposals for harnessing solar energy is to put solar panels in space. Either orbiting the Earth, or stationed on the moon, light waves could be converted into microwaves that pass through the atmosphere without losing any energy, then on to electricity on the ground. What I'm...

A solar model is used to calculate the expected temperature and density at all depths within the Sun. These results are then used to calculate the expected fusion rate within the Sun. We have confidence that the model is correct because it agrees with the observed characteristics of the Sun...

Homework Statement The Earth is approximately 1.5x10^8 km from the sun. what is the Earth's angular momentum about the center of the sun. Note the mass of the Earth is 5.97x10^24. Homework Equations The Attempt at a Solution I got the answer, but my question is, when finding the...

Homework Statement 1. Give a calculation for the approximate temperature needed for nuclear reactions in the sun? 2. Give a calculation for the period of two stars in the shortest possible orbit? The Attempt at a Solution 1. Our class just covered the first chapter of our book 'Stellar...

Because I was curious about this, I read here that, "Our own Sun is part of an open cluster than includes other nearby stars such as Alpha Centauri and Barnard's star." However, I cannot find any other pages claiming this, and the wikipedia entry on star clusters does not mention us being...

1. Question: In one region of a nebula the mean separation of atoms is 2.3x10^-3 m. What volume of the nebula contains enough atoms to make a star, similar to the sun, of radius 7.0x10^8 m within which the mean distance between atoms is 1.0x10^-10m? 2. Volume of sphere 4/3(pi(r^3 ))...

This is a pretty compelling short documentary about how all major religion is based on ancient astrology and sun worship. There are many points in this video that cannot be argued with or debunked. Pt 1. Pt 2. Pt 3. What do you think?

Homework Statement Earth is a satellite of the sun with an orbit radius of approximately 1.5 x 10^11 m. a) What is the Sun's mass? **Answer:** 2.0 x 10^30 kg b) If the Sun's radius is 6.96 x 10^8 m, how does the Sun's density compare with Earth's density? **Answer:** Psun = 1/4 Pearth...

I found this hilarious. This guy makes a pretty amusing argument for why we should destroy the Sun. http://destroythesun.com/" Surely, we should set aside our differences, band together and fight this threat.

I've had a good search through the archives and haven't found an answer to this question. Many apologies if this is old ground. . . Having read the threads on the Pioneer Anomaly a quick question to which I'm sure there is very simple answer (I just don't know what it is !): When...

Last semester in my astronomy class, we tried to find an equation that would fit the path of the sun based on measurements we took, but we realized that due to the change in the tilt of the earth, it wouldn't be a simple sine or cosine graph, and we dropped the subject. I was wondering if there...

Hi there Problem is: if hydrostatic equilibrium were violated by .01% so that 0.01% of the gravitational force were imbalanced by the pressure gradient, estimate how long it would take the sun to change its radius by 10%. My attempts at solving problem: My feeling is that the...

I'm writing an article in a plastic modeling magazine talking about scale weight. Plastic models come in many scales, i.e. 1/72 or 1/48, etc., so my article talks about what weight a model would be if it was also scaled properly for weight. For instance, a 2000 lb car, at 1/72 scale, would...

Gday all, I was just wondering if we would experience a (very small) centrifugal force due to the Earth's rotation around the sun or not. I don't think there would be because the Earth and everything on it is in a state of free fall around the sun, but I have been told there would be a...

Here we have got a very long rod (100 million km length or so) built/placed on the lunar surface (near equator) and directed towards the Sun (imagine that Moon is in synchronous rotation with Sun and therefore that point (where this rod is built) is always looking at the Sun). The distance...

Will the gas planets become solid? Since they are no longer receiving heat from the Sun?

Hi so I am doing a presenation, on the indirect search for the neutralino from the sun at amanda In short: neutralinos are graviationally captured and settle int he sun.. they decay to produce neutrinos.. we detect the neutrinos at the amanda detector through muon productionSo what I am...

I've been reading this evening that the Sun went Dark last night for just about a min. Is this true or are people just blowing smoke?

The history of our understanding of the sun is a very rich area. Ancients believed the sun was a god while we now know the sun is an enormous body of fusion. What I would like to discuss is how the scientists thought the sun worked after the development of the basics of thermodynamics but...

Hello, I'm currently studying general relatively and am trying to plot orbits of planets around the sun using the schwarzchild metric. I've worked out the geodesic equations, working with c=1 to simplify things, and written a MATLAB script to plot trajectories, but I'm struggling to work out...

How much is space bended at the surface of the sun, only due to gravity? And how can it be calculated ?

I am currently researching how the sun's steady increase in luminosity is affecting the four inner planets. It's a fascinating subject. I haven't done any of the calculations yet (mostly because I am not that advanced in math yet), but I was watching a show called, "The Universe." On this...

Would someone please correct my train of thought on this? I understood that the Earth's position in the Solar System is related to the gravitational attraction between the Earth and the Sun. If this thought is correct, then when the Sun enters its Red Giant phase, the Earth should be pushed...

It will be interesting to see if anything comes out of this. Sounds too good to be true. Continued... http://news.yahoo.com/s/ap/20110227/ap_on_bi_ge/us_growing_fuel

Homework Statement if: H = Local Hour Angle Lat = Latitude. Dec = Sun Declination. cos(H) = -sin(a)-sin(Lat)*sin(Dec) / cos(Lat)*cos(Dec) I wand to get The value of Lat . The Attempt at a Solution I Tried to make it simple By : 1 - multiply both sides by the denominator 1-...

If our sun was replaced by a pulsar, would our solar system be sucked into it because of the increased gravity? How long would it take? Would we burn up because of the increased heat? How long would it take? Does it still emit visable light or only x-rays etc..? Would the light on Earth be...

Hi friends! I have recently started a small project where I had hoped to build a simple sun tracker. My initial plan involved 2 Photovoltaic cells mounted at either end of a panel which was attached to a shaft which was then attached to a small DC motor. Both cells were hooked to the motor...

Does sun rotate around itself? Do all of stars rotate around themsilves? If so, what is the origion of this rotation?

For my engineering class, my professor asked us to estimate the total energy output of the sun. The only tools we are allowed to use (for now) are: 1) A thermometer 2) A graduated cylinder 3) A container of water 4) An umbrella We are only allowed to use information that we ask for, or...

Consider a photon of a certain frequency emitted from a distance slightly greater than the event horizon of a black hole. It seems possible that if a certain low frequency photon is not able to escape (due to becoming infinitely red-shifted), then a photon of a higher frequency emitted from the...

How much slower is time ticking inside the Sun, compared to the surface, and how can it be calculated?

I was just wondering why, if the gravitational force exerted on it by the Sun is greater than the one exerted on it by the Earth, the Moon stays in orbit around the Earth? Is it due to angular momentum or are there any other factors?

Homework Statement Knowing that the Earth spins around the Sun for 365 days and the distance Earth->Sun is 1.5x10^11 m, what's the mass of the Sun? Homework Equations F=G Me x Ms/distance^2 where Me - Mass of Earth, and Ms - Mass of Sun In some literature, I noticed that for...

How can one determine the color of another planet's sky from its atmosphere composition and parent star color? Earth's atmosphere is blue for most of the day, then turns red at sunset. Mars is sort of the opposite: it has a red sky which turns to a bluish hue at sunset. Until someone tells me...

I have been doing some study on the theory of relativity and it has got me thinking. We say that the Earth revolves around the Sun but from what reference frame? From the reference frame of Earch, we are stationery and the Sun simply spins. Why is any reference frame more accurate than another...

Homework Statement Estimate the force on Earth due to the pressure of the radiation on Earth by the Sun. (At Earth's orbit, the intensity of sunlight is 1.37 kW/m^2.)Homework Equations Radiation Pressure=I/c Pressure=F/A Using SA of earth=510,072,000 km2 The Attempt at a Solution So I have...

Q. Our present theory of the sun and the mechanism of thermonuclear fusion inside it predicts that the following reactions occur in the sun. 1H + 1H --> 2H + antielectron + neutrino 1H + 1H --> 2H + antielectron + neutrino electron + antielectron --> photon + photon electron +...

Homework Statement Our present theory of the sun and the mechanism of thermonuclear fusion inside it predicts that the following reactions occur in the sun. 1H + 1H --> 2H + antielectron + neutrino 1H + 1H --> 2H + antielectron + neutrino electron + antielectron --> photon + photon...

Homework Statement Assuming that the Earth describes in one year a circle, of 92500000 mile radius, whose center is the sun, how many miles does the Earth travel in a year? The Attempt at a Solution How does knowing the radius of the Earth help me with this problem? I don't need...

I've recreated one of the first experiments I did in Chemistry many times - Water electrolysis to split it into Hydrogen and Oxygen, and prove the existence of hydrogen with a burning splint that goes "pop" in the test tube. The Sun is a massive ball of hydrogen, that uses Nuclear fusion to turn...