Orbit Definition and 1000 Threads

First� Length contraction is an accurate phenomenon, and I am not proposing an alteration of views on this observed effect on a fast moving object viewed from reference perpendicular point of trajectory (a slice through simultaneous reference space). This slice of 4-space-time is of utmost...

This is taken from britannica encyclopaedia.The entire Milky Way system rotates around thegalactic centre, but the various constituent objects do not rotate at the same velocity. Stars distant from the centre travel at lower speeds than do those closer to it. The Sun, which is located relatively...

How fast do electrons orbit a nucleus ?

The sun has all the planets in it's orbit just like we have our moon orbiting us. Well O.K not exactly but similar. Well the moon is slowing Earth down and slowly pulling us closer to it. Is it possible that all of our 9 planets can partly pull the sun toward us? and do you think that we can...

I was pondering an idea that recently came to me. Would it be at all conceiveable for several small "planets" (smaller or equal in mass to our moon) to orbit around eachother with no large parent planet. For example and clarification, two or more planets with an unprecedented similarity in mass...

What are they and why only three per orbit?"mmm, sacralicious"- HJS

I have heard that the Earth orbits round the Sun not because of gravity, but massive objects like the Sun warps space-time around it so the Earth will always follow the straight geodesic, so as space-time is curved the Earth will follow that. Is this true?If the information above is correct...

Hi, hopefully any answers to this question will help any physicsforumers with the electron orbiting nucleus mental-image atom model to abandon it in favour of...... what ever is the best mental-image atom model.When a teacher tells a student that the model that electrons orbit the nucleus is...

If our sun goes red giant and engulfs the Earth, how long will the Earth continue to orbit inside the sun? If Sun rotates, will the Earth spiral toward Sun's center or it'll spiral away from it?

I believe I solved this. Is this solution true? Can please anyone just check?

Hi! This is a problem from my physics 1 high school course. I've tried using the first and third equations to determine period (answer of 8326.9544s.), however that was incorrect and I never even touched G. I'm not sure where to go from here at all. Any help is appreciated!

I am pretty confused where to even start with this question, which is not a good thing less than a week before the final :(. One thing in particular that I don't get is that I thought we were using the Clebsch-Gordon coefficients for ##\vert jm \rangle ## states, not for ##\vert J, J_z \rangle...

a) Eg = Gme/r^2 r = √Gme/Eg r = √[(6.67x10^-11 N*m^2*kg^2)(5.98x10^24 kg)]/(4.5 N/kg) r = 9.41x10^6 m h = r2 - r1 h = 9.41x10^6 m - 6.38x10^6 m h = 3.03x10^6 m that's over 3000 km. Did I not use for right equation? Is Eg not 4.5 N/kg? Also for b), isn't the force of gravity the centripetal...

I have yet to decide on values for the mass of the fixed object, M, the mass of the moving celestial body, m, the initial velocity, v, and the distance between the two objects, r. I will most definitely decide on a larger mass M because I would like the celestial body to spiral in towards the...

The exercise is to compare numerical and analytical solution. I have worked out the code from earlier exercise (see code under this text), but I don't understand how the analytical solution works. I have tried to use the equation r(theta) = a(1-e^2)/(1+e*cos(theta)), which is OK but I don't...

I want to understand this topic but I can not understand very well so please suggest any reading for good conceptual grasp of this topic.

The Earth's orbit around the Sun is an elliptical orbit. Why is that so? Does that mean Sun, much like Earth bulged at some points which makes the gravitational force between Earth and Sun stronger at some points and weaker at some comparatively?

Recently i read, that GEO orbit actually isn't enough for a space elevator, since its weight would pull it down, either it needs constant thrust, or build it much taller than 33.000 km, so upper GEO parts pull it up. That further lowers its plausibility level. Any other methods? Build a tall...

Hi, everyone can you help me with this question, please?

Summary: Achieving speed of light with Earth's rotation Excuse my ignorance, but I think of dumb things. If you theoretically built a strong, lightweight cable that traversed over 2.5 billion miles attached to the rotating Earth, the tip would be traveling at or greater than the speed of...

I tried it, but I am not getting no of the given answers According to the statement, it is saying that 3 KE (in the orbit ) = ΔUg So, beeing R the radius of the Earth and R2 the radius of the orbit: 3 (1/2)(GMm/r2) = -GMm/r2 - (-GMm/R) Canceling out the GMm: (3/2)(1/r2)= (-1/r2) + (1/R)...

This is something that one seldom stops to think about, but I suddenly thought of it myself: Why do oceans look deep blue when photographed from orbit? Oceans look blue when looked from the shore because they are reflecting the sky... But the atmosphere doesn't look deep blue when photographed...

In a circular orbit, the 4-velocity is given by (I have already normalized it) $$ u^{\mu} = \left(1-\frac{3M}{r}\right)^{-\frac{1}{2}} (1,0,0,\Omega) $$Now, taking the covariant derivative, the only non vanishing term will be $$ a^{1} = \Gamma^{1}_{00}u^{0}u^{0} + \Gamma^{1}_{33}u^{3}u^{3} $$...

From CNN: These two dead stars zip around each other every seven minutes https://www.cnn.com/profiles/ashley-strickland-profile By Ashley Strickland, CNN Updated 2:48 PM ET, Wed July 24, 2019 (CNN)While searching the skies for brightness and blinking, the California Institute of Technology's...

Good evening, This week I had a discussion/conversation with one of my coworkers about the posibility of a mass from outer spate that could start orbiting the earth. The issue is, I believe you cannot, whithout a proper change of energy (velocity) start orbiting a celestial body just by coming...

first of all, I tried to obtain the energy eigenvalues of the Hamiltonian, by using the equation ##det(\hat H -\lambda \hat I)=0## ##\gamma V\delta(z)(\hat z \times \mathbf{p}) \cdot \sigma=\gamma V\delta(z)(p_x\hat j-p_y\hat i)\cdot(\sigma_x\hat i + \sigma _y \hat j)=\gamma...

Okay, so let's simplify things and look at the ideal case, where the 2 masses are the same. Well, this gives us a sine wave pattern to the orbital velocity. Consequently, the acceleration would follow a cosine wave since the derivative of velocity is acceleration and the derivative of sine is...

Quick question for the people to better understand orbital mechanics. Due to large mass concentrations on the moon's surface, there are only four orbital inclinations that a satellite can be at to maintain an indefinite orbit: 27°, 50°, 76°, and 86°. My question is this: If a satellite was...

How does GR predict the Earth's orbit around the sun? Newtonian mechanics predict a gravitational force that is a function of the two masses. Is the geodesic path of the Earth a function of both the sun's and Earth's curvature of space?

Summary: orbital path of an object Good morning I would like to ask the members of this forum their opinion regarding the object, which path I present in the image. The x-axis is the azimuth (towards me, the observer), and the y-axis the altitude. So it goes up in the trajectory shown (from A...

So using conservation of energy where v0 = 7000 m/s $$ K_{i} + U_{i} = K_{f} + U_{f} $$ $$\frac{1}{2}mv^{2}_{0} - \frac{GMm}{R} = \frac{1}{2}mv^{2} - \frac{GMm}{r}$$ where R = the radius of the Earth and r = the distance from Earth's center plus the height its orbiting $$v =...

Distance is d=1/0.07 = 14.3 parsecs The Doppler shift of one star is, Δλ = 512 - 512.04 = -0.04 So the radical of the velocity of the star is = (-0.04/512) x (3.00 x 10^5 km/s) = 23.4km/s which is the same for both stars because they have the same mass. This is as far as I've got.

If I had an object in an orbit around the Earth that I kept continually shaded from the sun, how cold would it get? Assuming the shade device was not physically connected to and was sufficiently far away from the object to not radiate any heat to it. And if I actively adjusted how much shade...

I've got the start of a plot forming in my mind, and I'm wondering if it's likely to be supported by physics at all. My basic understanding: when astronauts go to the International Space Station, due to the speed at which it is travelling, time passes ever-so-slightly slower for them. This...

I'm reading through a derivation for the energy of a satellite in an elliptical orbit. Shouldn't EO-2 read as: ... and not as shown in the following?

Homework Statement A) By examining the effective potential energy find the radius at which a planet with angular momentum L can orbit the sun in a circular orbit with fixed r (I have done this already) B) Show that the orbit is stable in the sense that a small radial nudge will cause only...

Why do you need a weak spin orbit interactions in individual electrons in order to use the LS coupling? From what I know, we are free to combined angular momentum whenever [L1, L2]=0 and this should be true on the orbital angular momentum (and spin) of the electrons because they are...

A bunch of years ago, I read about a very small object following Earth in the same orbit, but not in any danger of collision with Earth (at least in the next few billion years). Anyone know about the object. I have done a search but cannot find any reference to what I think I read about?

Homework Statement Consider an elliptical orbit of a satellite (of mass m) around the Earth (of mass M >> m). The perigee is at ##r_A## and the apogee at ##r_B##, as measured from the centre of the Earth, itself located at one of the focal points of the ellipse (see Fig. 1). We work in an...

does the Perigee and Apogee of the Earth's orbit relative to the seasons affect the temperature of our summers?

$$V_{HE}=\sqrt{\frac{\mu}{a}}$$ What is the rationale for this formula when we can determine the change in velocity from Earth's orbit to transfer orbit using the vis-viva equation? Likewise, what is the use of defining the radius for the sphere of influence for interplanetary transfer...

Soooo, hi PF, it's been a long time since I needed your help, but here I am again. I've been doing some worldbulding lately and I came up with this idea of a world in which civilisation and life are much, much older than in ours. Yet it isn't as developed due to some kind of natural disaster...

I believe that GR cannot describe exchange of classical intrinsic angular momentum and orbital angular momentum. The exchange of orbital and intrinsic angular momentum requires that the momentum tensor be non-symmetric during the exchange. GR cannot accommodate a non-symmetric momentum tensor...

Assuming it happens and that the Deep Space Gateway happens as a base for Moon landing and further exploration. What sort of orbit would it have in relation to this use? I have I-searched but not found any detail. Thanks.

Homework Statement A Satellite is brought up into a geostationary orbit (altitude 35800km measured from the surface of the earth). Satellite weights 1000.0kg. How much work is required to bring satellite from a surface of the Earth to geostationary orbit? Homework Equations Newton's law of...

Assumptions: 200+ years from now Asteroids have been moved to all Lagrange points, and at least 90, 180, and 270 degrees on Earth's' orbit for mining, and shielding humans and equipment Tech to acceleration/decelerate at 1 gravity without need to carry fuel. (My main fiction.) Direct line of...

Homework Statement A tight pair of stars orbiting with circular paths at a distance a, the weight of the stars is the same: M1=M2=M What period T and frequency f is the pair circulating? Explain the results generally with G, M, a. Homework Equations Kepler's law M1+M2=a^3/T^2 The Attempt at a...

Hi, I'm trying to deduce orbit velocity of a particle with mass from Schwarzschild metric. I know for Newtonian gravity it is: $$v^2=GM\left(\frac{2}{r}-\frac{1}{a}\right)$$ The so called vis-viva equation. Where ##a## is the length of the semi-major axis of the orbit. For Schwarzschild metric...

This is probably a fairly simple question, but I am struggling with it. My question is: Would you experience the effects of gravity if orbiting in a stable or circular orbit close to a black hole? This stems from my mental image of the International Space Station (ISS). There is obviously...