Orbit Definition and 1000 Threads

Quick question that maybe someone here could answer. I could probably dig up a bunch of math equations and answer it too, but I'm guessing someone here already has a good idea about the answer. Placing the Sun at the center of a sphere whose radius is equal to the distance of the Sun to...

Let be a photon in a circular orbit (r=3M). I want to know the period measured by a stationary observer at this radius. Because we are working with a photon we cannot 'talk' about proper time, that's why I don't understand how can I calculate this. If I had a massive particle I could do...

Homework Statement Homework Equations F = G(m1m2/r2) The Attempt at a Solution Well the height of Mt. Everest is 8,848 m. And I'm guessing the no atmosphere and not turning on an axis is just to setup the ideal problem. But from there I don't know how to set up the equation so...

I know that the generators of the Poncaire group that are associated with *orbital* angular momentum belong to an infinite dimensional representation, i.e. \begin{equation} L = \frac{\partial}{\partial \theta} \end{equation} Also the spin generators are associated with some finite...

Homework Statement Show that a satellite in low-Earth orbit is approximately P = C(1 + 3h/2R_E) where h is the height of the satellite, C is a constant, and R_E is the radius of the earth) Homework Equations p=C(1+3H/2R_E) p2 = (4∏2)/(GM) * a3. (G - gravitational constant, M - mass of the...

Just curious, does anyone know what are the equations for the displacement-time graph of a Keplerian orbit? The horizontal displacement-time graph should be somewhat sinusoidal, the vertical one cosinusoidal, or vice versa.

Homework Statement Communications satellites are placed in a circular orbit where they stay directly over a fixed point on the equator as the Earth rotates. These are called geosynchronous orbits. The altitude of a geosynchronous orbit is 3.58e7 m. Homework Equations v=2∏r/T...

A comet orbits a star. At its closest approach (r=4*10^10 km) it has a speed of v=50 km/s. How fast is the comet at its maximum distance (R=10*10^10 km)? Could someone verify my results? F=GMm/r^2=mv^2/r f=GMm/R^2=mV^2/R F/f = R^2/r^2 = Rv^2/rV^2 -> R/r = v^2/V^2 R=2.5r -> 2.5r/r...

Homework Statement A 320kg satellite experiences a gravitational force 800N. What is the radius of the satellite's orbit? Homework Equations G m1m2 / d^2 The Attempt at a Solution I started with 800N = (G(320kg)(5.98(10^24)kg) / d^2 After some algebra and rounding I ended up...

Homework Statement You may assume circular planetary orbits. a. Calculate the velocity (relative to Earth) at Earth's orbit of the Hohmann transfer orbit that is tangent to both Earth's orbit and Jupiter's orbit. b. calculate the minimum velocity necessary to launch a spacecraft from...

Hi, I am completely stuck on this problem that has been given to us. I must solve a set of 2nd order differential equations using Euler's method. It is for a geosychronous orbit of a satellite, meaning the orbit is circular and the velocity vector is perpendicular to the radius vector...

If an asteroid was moving in the opposite direction of the moon, could it slow it down enough when it hit it to cause it to crash into the earth. and vice versa, could it be going the same direction and acceleration it enough to excape the Earth's gravitational pull? If so, about how large would...

2 closely orbiting massive objects are predicted to deserve the fabric of spacetime so much that they will release a ripple of gravitational waves. When geavitational waves are released, they slowly loose velocity energy and spiral into one another. 2 pulsars were discovered orbiting each other...

Einstein predicted a slightly quicker orbit for planets very close to the sun that will deviate from Newton’s gravitational laws very slightly. Later observations, as we know, have proved correct and General Relativity holds up. But what is the perceived reason as to why this is? What is the...

Using iteration I've got a satellite flying around two gravity sources. (See picture) When using the iteration over a 100 times I see that TE, total energy slowly sinks so I need to make a correction after each iteration to insure that TE is constant. Trouble is I have several...

I'm world-building for a SF-story and need some help figuring out what the ocean tides would look like. My planet orbits a close binary star system; it does not have any satellites itself. The mass of the binary is 5/3 Mo [solar masses]. The orbit is closer than that of Earth and is highly...

Homework Statement Consider a satellite in a circular, low-Earth orbit; that is, its elevation above the Earth’s surface is h ≪ R⊕. Show that the orbital period P for such a satellite is approximately P=C(1+ 3h/[2R⊕]). Homework Equations P2 = (4pi2)/(GM) * a^3. (G - gravitational...

Hey, I was trying to prove to myself an expression for the total energy, and I got stuck Here is the picture (it's transparent, so I won't embed it here). The problem I seem to be having is when I observe these two points where the speed is in its highest and its lowest. Since in these...

Pretty straight forward. The same generally holds true with moons belonging to the same planet. If we don't have concrete reason why this occurs, are their any strong theories?

Hi, Would the difference in the distance between the Earth and the sun when the Earth is in perihelion and when it is in aphelion be considered a parallax? Thanks,

Homework Statement How much charge would the Earth and Sun need to knock the Earth out of orbit. Then, assuming the distance from one proton to another and the length of one electron to another is 197 pm, find out how large of a block you would need of protium located on Earth and how large...

Under the influence of the coulomb field of charge +Q, a charge −q is moving around it in an elliptical orbit. Find out the correct statement(s). (A) The angular momentum of the charge −q is constant (B) The linear momentum of the charge −q is constant (C) The angular velocity of the charge...

Homework Statement Find the eccentricity of an orbit given the masses, cartesian position components, and cartesian velocity components for particles 1 and 2. The case is reduced to the xy plane. Homework Equations I am attempting this problem using reduced mass from the center of mass...

1. How fast are stars orbit speed in elliptical galaxies (from and to) 2. How big differences are there typical between Perigalacticon and Apogalacticon in a. elliptical galaxies and b. spiral galaxies?

A comet near the sun whose orbit is________ would never be near the sun again is called what? My options are elliptical (I know its not this one), circular, hyperbolic, apogee, and following an inverse square law.

When a satellite is affected by resistance against orbit motion, for example from thin atmosphere or solar wind, it will as a result of this decelerates - but in that process it will decrease slightly toward the earth, and therefore following accelerate too. How can the new orbit speed be...

Hello. I read from a calculus book (Larson) that shape of comet's orbit is determined by its velocity in following way. Ellipse if v < sqrt(2GM/p) Parabola if v = sqrt(2GM/p) Hyperbola if v > sqrt(2GM/p) where p is the distance between one vertex and one focus of the comet's orbit...

Is it that faster we move through space, the slower we move through time? Is it that we're moving slower through time than if the Earth wasn't orbiting anything? And on a wider scale like, the Sun orbiting the centre of our galaxy, and our galaxy moving through space. How would time be...

The Earth has at times been struck by very large asteroids but this has not knocked our planet out of it's orbit. Why not? Does the Earth have some method of 'self correction'? Or is it not a very 'fine tuned' system so that a few impacts really won't make any difference? Alternatively have...

I was looking at JP Aerospace's Airship to Orbit project: http://www.jpaerospace.com/atohandout.pdf I was with it until the third phase: What is the mechanism of electric propulsion? Is it simply a propeller? (I was under the assumption that a propeller would be fairly useless at that...

Homework Statement A satellite orbits the Earth once every 120 minutes. The satellite is in a state of free fall. What is meant by the term free fall? How can the height of the satellite stay constant if the satellite is in free fall? [3 marks]Homework Equations none The Attempt at a Solution...

Is it possible to calculate the historical whereabouts of the asteroid belt, as it seems to be moving ever outward due to the radiometer effect? Can it be calculated, for instance, where it was 1,000 years ago? 100,000 years ago? Etc. In particular, I'm curious as to whether the science is...

Has an amateur rocket ever made it into orbit?

It is said in the literature, I believe, one needs several nights of observations to calculate an orbit for, say,an asteroid. Using celestial mechanics mathematics and methodology, one produces the six orbital elements. It seems to me that most introductory texts on the subject, talk about...

Hi, folks. I'm new here and came looking for some expert input on this odd question that came up as a friend and I were considering a hypothetical. Suppose a hand grenade were orbiting the sun---say, half way between the orbits of Mars and Jupiter. And to make things easy, suppose that the...

Suppose we have a satellite in an elliptical orbit around the Earth with the major axis pointed towards some fixed point in the heavens. What is the minimum number of rocket burns so that the major axis is rotated 90 degrees and the final and initial energy are the same. Is the number 2? At...

I came across the following at Ned Wrights website and wondered [a] What does the boldface statement mean? [b] What is thought about the statement that "Cosmological expansion of the Earth orbit around the sun is negligible but not zero" instead of "its not been determined"...

Hi, I am having difficulty understanding the following: \int^{2π}_{0}(x+y)\,dθ = \int^{2π}_{0} 2a\,dθ = \textbf{4}πa where x and y are the generator lines of an elipse, a is the semimajor axis and θ is the angle formed by x and the major axis. I understand that x+y = 2a. However I...

Homework Statement I'm trying to write a program with three bodies, two in orbit around a large central object. The main object orbits fine, that was dealt with earlier. I'm having trouble making a smaller object that is the only object whose position is dependent on the position of both of...

Homework Statement How much work is done moving a 1500 kg spacecraft from the Earth's surface into a fixed orbit at a height of 300 km above the Earth's surface? Homework Equations Eg = -Gm1m2/r Ek = 1\2mv^2 mass of earth: 5.98 x 10^24 kg radius of earth: 6.38 x 10^6 m The...

Homework Statement Our teacher gave us a formula and ask us to proof it, when I asked him for more detail he told I'm looking for radius equation in this formula. The formula is: G.Me.m/r*2=m.d*2r/dt*2 . means Multiply / means Divide * means Power, r to the power of 2 is r*2 I believe target...

Homework Statement A)Calculate the magnitude of the angular momentum of the Earth in a circular orbit around the sun. B) Is it reasonable to model it as a particle? Yes, considering the size of the Earth in comparison of its orbit around the sun it is reasonable to model it is a particle...

From what I understand (and also assuming that the mass of one body is much greater than the other), if we had a body performing a circular orbit, and we put more (or less?) energy into the orbit by changing the speed of the body, the orbit will become more eccentric, i.e. elliptical. My...

Homework Statement A comet of mass m moves in a parabolic orbit in the ecliptic plane (the plane of Earth’s orbit), so its perihelion distance ρ (its closest distance to the Sun) is less than Ro (the orbital distance of the Earth around the Sun) and occurs when θ = 0 for the comet. (The...

Homework Statement A particle of mass m is acted upon by two forces. P(t) in the x direction with magnitude p(sinkt) and Q(t) acting on the line y=x with magnitude qsinkt. At t=0 it starts at (b,0,0) and velocity p/(mk) moving toward the origin. Prove the particle is in an elliptical orbit...

Homework Statement Comet Halley approaches the Sun to within 0.570 AU, and its orbital period is 75.6 years. (AU is the symbol for astronomical unit, where 1 AU = 1.50 x 1011 m is the mean Earth‐Sun distance.) How far from the Sun will Halleyʹs comet travel before it starts its return...

Homework Statement The problem deals with a sports player being able to hit a golf ball at a speed of 92 m/s. The first part says to find the size of an asteroid that would have that speed as an escape velocity. The second part says that if he hits the ball at 80 m/s, what will the...

Hi, I've got a problem here, that I'd like to discuss before trying to implement any sort of solution. Basically I've got a planetarium simulation, in which I'd like to plot a patched conic trajectory ahead of a spacecraft . The planetarium only simulates two-body gravity, and switches...

I know it has something to do with gravitational pull, but I don't know why.

Is it because of their different masses?