Sun Definition and 1000 Threads

I believe that I have compiled compelling evidence from the TRACE, SOHO and YOHKOH satellite programs to suggest that the sun has a solid, electrically conductive surface that lies underneath the photosphere. You can find my website with lots of video and photographic evidence to support this...

is the sun moving simple harmonically up and down also?

ok... So, we see the sun everyday, right? So let's say you are standing on one point of the Earth looking at the sun rise... At where must you point a laser cannon in order to hit the sun dead centre? and why? :confused:

My Professor posed a riddle in class today. He said "Question: Name two things that signify a trip around the sun". I not very good at riddles, but I know that Earth travels around the sun once a year. Thus the changing of seasons could be argued as signifiers (earth rotates on it's axis as...

The problem is this: Given sun of mass M and a body of mass m (M>>m) a distance r from the sun, find the time for the body to 'fall' into the sun (initially ignoring the radius of the sun). Our first equation is therefore \ddot{r} = \frac {GM}{r^2} . I am able to integrate this...

I am beyond lost with the question, so any help would be greatly appreciated. Consider a solid, rigid spherical shell with a thickness of 100 m and a density of 3900 kg/m^3. The sphere is centered around the sun so that its inner surface is at a distance of 1.5×1011 m from the center of the...

It appears that Linus Torvalds has joined the OpenSolaris Community Advisory Board (CAB). http://richteer.blogspot.com/2005/04/opensolaris-community-advisory-board.html In the meanwhile, rumors are circulating the CAB that Linus will be announcing a fork of the Linux kernel to Sun's CDDL...

Orbits What does our galaxy orbit? more questions will follow once previous ones are answered

I have a question for you all. I asked my Physics teacher this in school not so long ago. I made an animation of it on a little art thing (which rocks btw, I suggest you all use it for your examples or theoreys) http://artpad.art.com/gallery/?idilmbnxbps In a nut shell: You're on a...

i have a feeling this was answered a while ago. however, my problem is, a shere of water (as it is in space) is launched into the sun from here, assuming it hits no graviational fields and continues on it's path into the sun, the following will happen: 1. the water, frozen from its trip...

A comet moves in an elliptical orbit around the sun. It's closest approach to the sun is 0.59 AU and its greatest distance form the sun is 35AU. If the comet's speed at its closest approach is 54 km/s what is the speed when it is farthest away? Angular momentum is conserved and the gravitational...

Could it be that all the stars we see in the sky no longer exist?

We all know that stars, for example the sun, are made up of particles such as hydrogen, but a friend challenged me recenlty asking HOW we know this, and I was forced to admit that I didn't know the answer... so how do we know? probably a simple question, but my so-called "expertise" is more...

Hello, does anyone know of any good resources for solar path data? Like what angle in the sky the sun is at for different parts of the year. Thanks, AL

I need Help! I've got this question which I can't Answer : If the mass of the Sun is reduced by 1% and the Earth's velocity is also reduced by 1%, what will be the trajectory of the Earth?

Can somebody explain how to calculate the sun's angle in the sky at a certain time of day? It is wanted to calculate the length of an object by it's shadow.

Was the sun ever a blue star in the early stages of its life? does this mean for a proportion of the time of the 5 initial billion years of the suns lifetime, the planets were cooking because of the suns initial powerful (blue) heat?

Hi everyone, I am fairly new to PF. So I start off with a rather strange idea, derived from SR. According to the first postulate of Special Relativity, it would be more accurate to say that the sun revolves around the earth, because we are stationary relevant to the earth, right? Correct...

It is said that the moon's tidal forces on the Earth create differential torque which causes a slowing of the Earth rotation. It is said that this causes the moon to increase its radius of orbit. The remarkable result is that rotational energy of the Earth is transferred to the moon to increase...

Alright. Now, I understand that the Sun is 1/2 way through its complete H-He fusion cycle, and I realize that after this fusion cycle, it will pass through all the elements until Fe, (i don't know whether it passes through each element in 7 seconds, or it takes 7 seconds for each element). My...

I can't seem to obtain the right answer using the escape velocity formula. I think my problem is with the gravitational constant. I would like to find the escape velocity of the sun. v_e=\sqrt{\frac{2GM}{r}} or v_e=\sqrt{\frac{2\mu}{r}} v_e_\odot=617.54(km/s)...

Hi ! first, excuse my english, I'm just a poor french student... and we are so bad in languages here... anyway.. I'm trying to make a little program which could calculate the motion (and some other little things) of n bodies linked with gravitationnal interaction. (my final aim will be to...

Hi, I have a question that and I am unable to come up with a consistent and simple answer to. If we consider a coordinate system centered at the earth, then all planets, the sun and indeed the rest of the universe is rotating around the Earth in a very complicated way (as measured in this...

New question: centripetal force? I can't seem to get the right answer... R = 1.50 x 10^11 and I figure that 1 day/rev = 86400 sec/rev So: \frac {2 \pi 1.50 * 10^{11}}{86400} is the velocity, and then plug that into \frac {v^2}{r} but I keep on getting 700 something..what am I doing...

Why isn't there a more pronounced effect from the Sun on tides? The distance from the Earth to the Sun seems negligible considering the mass of the Sun. While typing this out and thinking about it, the most reasonable explanation I can come up with is that the Sun has so much mass that the...

Why does a bight object like the sun have negative magnitude? TY

I was going to make a poll including each sign, but there are only 10 options. Just post your sign (and Moon's sign or Ascendant if you know it). The only thing I'd anticipate is an absence of Taurus and Capricorn. Unsure, born on the cusp? Be sure Sagittarius (Aquarius Moon)

If the Sun is 98.4 % Hydrogen and Helium by mass, and 99.8% by number of atoms, why does it radiate a continuous spectrum of light? Why doesn't it radiate a bright emission line spectrum only at the Hydrogen alpha, beta, gamma, etc. lines plus the Helium lines, and little or no lines at...

Could someone help me start this problem. My mind it in the angular momentum mode and I am having trouble seeing where to start on this one. :confused: The sun's radius is 6.96E8m and it rotates with a period of 25.3d. Estimate the new period of rotation of the sun if it collapses with no...

The Earth has an orbit of radius 148 million km around the sun. What is the speed of the Earth on this orbit? dont know how to do it i have used a couple of different formulas and haven't gotten it right can anyone help?

hey there, i am having trouble with what should be a really easy question! ********* calculate the mass of the sun assuming that the Earth's orbit is circular and with a radius of 1.5 * 10^8 km i got the period of the Earth's orbit around the sun in seconds: 60*60*24*365.25 then used...

What do members think of this: http://arxiv.org/abs/astro-ph/0411163 ? Garth

What is the acceleration due to gravity of the sun at the distance of the Earth's orbit? i have no idea where to begin. Help

Ok, I keep trying to do the following problem: ----The asteroid Icarus orbits the Sun like the other planets. Its period is about 410 days. What is its mean distance from the Sun? (Hint: You can derive the mean distance with the paramters known for the Earth: Period of the Earth = 365 days...

Does anyone know or is it possible to know how much percent of Earth's motion is due to the effect of suns gravity? I am thinking very close to 100%, but not exactly 100%. If it were 100%, the Earth's orbit would be a perfect circle; not to mention the orbits or the other planets. So what causes...

The following site shows that when a sail is orientated so that it faces away from the sun, the net force is pushing outwards from the sun and is also opposing the orbit. http://solarsail.jpl.nasa.gov/introduction/how-sails-work.html It makes sense that the craft should slow down, but why...

I fear that I am way out of my depth here, being a mere mathematics student but anyway... We have been asked by our mathematical modelling lecturer to calculate the quantity of water required to extinguish the sun. I'm pretty sure that the exact physics and processes of the sun are not...

Well, i know that sun transit time is when the center of the sun crosses an imaginary line (the meridian) in the sky of the observer (or the given city). But, what I'm not understanding is why the sun transit time is different when we compare Toronto and Boston. They are both relatively close...

We're asked how long would it take for the sun to cool down if nuclear energy production suddenly came to a hault This is the question asked in one of my lecture courses given that the radius of the sun is ~ 10^9m, mass ~ 10^30 kg, luminosity ~ 10^26, and G = 6.7x10^-11 Am i correct in...

Concerning this issue, I would like to introduce to you the architectonic approach on the structure of the celestial systems. It shows how an architect observes the laws of the cosmos. I am revitalizing an ancient but moral concept that was proposed by Pythagoras and Plato, about two and half...

Stuck again with this "not so informational" astronomy book, and we need help with a question. What produced the helium in the Suns atmosphere, Jupiters atmosphere, and the suns core? :cry: can anyone help us?

Dear reader, here is a neat problem, but kindof over the edge. when it is about the same distance from the Sun as is Jupiter, a spacecraft on a mission to the outer planets has a speed that is 1.5 times the speed of Jupiter in its orbit. Which of the following describes the orbit of the...

Why do all the planets orbit in the same direction around the sun?

Global warming on retreat. The British press is usually in the top scaremongers when it’s about the potential disasters of Anthropogenic Global Warming. It’s about finished by now. See how elegant the retreat is: http://news.telegraph.co.uk/news/main.jhtml?xml=/news/2004/07/18/wsun18.xml

I know that when your skin is exposed to a lot of sunlight it turns darker in order to try to absorb some of the light's energy, which can help avoid burns, but why does your hair become blonde?

Through nuclear fusion the Sun slowly losses mass as it is converted to energy. The Sun also losses mass through coronal mass ejections. So after a large amount of time would this change in mass of the sun create a measurable change in the gravitational influence the Sun has on bodies in the...

is it possible to make a sun ? coz if we do , than we don't need things like fossil fuels to produce heat

Seeing "The Chronicles of Riddick" there is described a planet subject to melting distruction should one be caught out in the sunlight during its sun-star passover. Apparently things are O.K. if one stays in the shade. This has been thought not too scientific even by Ebert, a movie critic...

The photosphere is 4500 K The chromosphere is 10000 K The corona is 1,000,000 K The temperature increases as the distance from the core increases. This makes no sense to me. Any ideas? Thanks Nautica

Hi, how can I measure? I have'nt got any advanced tools (I have got a telescope only)! I think it is possible, because it was done in past. Thanks