Questions tagged [satellites]
Satellite is a generic descriptor for any body that orbits a much larger body. The term commonly refers to objects orbiting planets, like artificial satellites and moons, but it can sometimes also refer to planets, small stars, satellite galaxies, and other objects.
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Is a satellite revolving in Earth's orbit also affected by the gravity of the Sun or other planets?
The Earth revolves around the Sun and a satellite also revolves around the Earth. The Sun has a gravitational effect on all celestial bodies, so does it also have an effect on the satellite? If so ...
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Is the mass of Satellite + Earth system less than their individual masses?
I understand that when a Earth + Satellite system forms (satellite comes into orbit) the total energy is -ve. If the energy of the system when placed at infinity is 0 (assuming P.E and K.E is 0 at ...
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Disposing of Obsolete Satellites by Propelling to the Sun [migrated]
I'm not scientifically adept, so bear with me. Would it be feasible to retain enough fuel on new satellites/space stations, etc., that we could dispose of them when obsolete by sending them to the ...
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Is it possible for 4 satellites cannot render a position fix on Earth?
I recently learnt about how GPS works and how it uses the intersection of spheres to locate a person which got me thinking whether 4 spheres can always guarantee a position fix. My understanding is ...
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How to calculate losses due to diffraction?
Assume a transmitter with a laser source generating gaussian beams and is transmitted using a telescope with radius of aperture $a_T$. The light is collected at the reciever end using a telescope of ...
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How to use the orbital speed equation for more than one satellite orbitting a planet? [closed]
I am having trouble in applying the orbital speed, $v=\sqrt{\frac{GM}{r}}$ in the following problem stated below.Usually we have one satellite orbitting one planet.But in this case there are two ...
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Will a very long space ship orbiting the Earth appear to have gravity to someone inside?
My friends and I have several disagreements about this scenario:
Imagine a rigid cylinder that is the length of the diameter of the earth. At either end of this cylinder is a capsule with a person ...
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Basic: calculating a satellites height from its angular speed
A few days ago, while loooking at the night sky, I saw a satellite and I wondered if it would be possible to tell how far it is just by looking at it. The only possible naked-eye measurement that I ...
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Question regarding Time dilation of satellites
My name is Shaun Kant.
I was wondering about why the satellite's time is faster with respect to Earth's time. PBS space time mentions that fact. However, Wikipedia mentions that at the ISS (...
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Number of Geostationary Orbits
It is stated that there is only one geostationary orbit whose height can be calculated using:-
$H = [\frac{GM_ET^2}{4π^2}]^{\frac{1}{3}} - R$
But there can be more than one geostationary orbits if I ...
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Acoustic guitar pickups used in satellites: why? [closed]
Some years ago, a weather satellite manufacturer in the SFO bay area was buying small quantities of piezoelectric acoustic guitar pickups from one of the big music supply houses, which greatly puzzled ...
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Why don't we put satellites into an orbit where there is (almost) no time dilation/contraction compared to Earth's surface?
Consider:
On this image, if I understand correctly, the time dilation diagram is shown depending on the height for circular orbits. First in low orbit, time slows down relative to the surface due to ...
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If the Moon suddenly got heavier/lighter, would it crash into/fly away from the Earth, or would it stabilize at a different orbit?
If the Moon became suddenly gained 20% of its mass, would it come crashing down to the Earth, or would it just stabilize at a lower orbit? Similarly, if it suddenly lost 20% of its mass, would it fly ...
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How much does mass center of satellite oscillates about elliptic orbit as its spinning around the Earth?
I would like to know how much the real orbit of satellite can differ to the elliptic one.
Some perturbation of mass center position of the satellite must occur - Earth gravity accelaration changes as ...
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How can people be weightless on space station?
I had read it somewhere that on the space station, people are weightless. even though artificial gravity is created there, people are still weightless. how can this be possible if there is gravity, ...
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Why won't a pen work on the International Space Station?
Today, in my physics class, we were discussing the effect of microgravity (specifically on the ISS) on various objects of everyday value. I learnt that a normal pen wouldn't work in space (So they ...
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Distribution of Earth's mass and its role in the nodal precession of satellites?
From what I have read and understood so far, the nodal precession of a satellite in low Earth orbit is caused by the bulge equatorial of the Earth (caused by its rotation on itself) which moves the ...
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If a satellite is shut down, will it eventually reach the high temperatures of the exosphere?
If a satellite is shut down so that it neither generates additional heat from whatever internal energy source it might have, nor is able to dissipate heat by an active cooling system, will it ...
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Payload ideas for an 1U CubeSat [closed]
I don't know if this is the relevant site for such questions, but I am asking it anyway.
Our school has taken up a project on launching a CubeSat and I am part of the 45 contributing students. We are ...
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What is a 'satellite' in solid state physics?
During a course, my professor talked about satellites. He defined them as an excitation which results in an electron-hole pair, in a system of interacting electrons. So that the energy of the ...
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Orbital period around slowly rotating star in general relativity
I want to compute the general relativity prediction for the difference in period between clockwise and countercloskwise orbits of a planet around a star which has small mass $M$ and small angular ...
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Work needed to orbit earth
In school I have always been told that it's better to launch spacecrafts from around the equator to utilize earth's rotation.
Now, when wanting to theoretically put a large object with a lot of mass ...
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Orbital motions
Suppose two satellites are moving in circular orbits around the earth and then crash into one another.
My Question is this, how do we know that the bodies move in an elliptical orbit after the crash? ...
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How is the potential energy of a satellite/planet in orbit derived?
Recall that for a Hookian spring:
$F(r) = -kr$ (force vector and radius vector point in opposite directions, hence the negative sign)
Since negative work is a positive change in potential energy,
$$U(...
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Orbital height without the gravitational constant and the mass of either object [closed]
Is it possible to calculate the orbital height of an object using only the orbital period T = 93min, radius of the Earth R = 6378km and the gravitational acceleration at the surface of the Earth g = 9,...
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What does a Space radiator/cooler look like exactly? [closed]
I understand the principles of radiating heat to space using heat pipes and whatnot but what exactly do these devices look like in real world applications? The closest example for a space base ...
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Finding rate of change of the distance from an observer on earth to a satellite in orbit
This is a satellite motion related question. To give context, imagine a satellite orbiting Earth at a distance 'R' from the center of the Earth at constant velocity 'v'. An observer on the surface of ...
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Amount of Force to De-orbit a Satellite [closed]
Assume I have a Low Earth Orbit (LEO) satellite of mass $m$ and velocity $v$ that I would like to de-orbit, assuming I have a propulsion unit, how much force do I need to make it de-orbit, and how can ...
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Is it possible to make a satellite orbit Earth, the same way Earth orbits Sun? ( Same orbital path pattern)
Is it possible to make a satellite orbit Earth, the same way Earth orbits Sun? (Same orbital path pattern)
Earth's Orbit
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Would obliquity and precessional changes of Earth affect the accuracy of GPS-based measurement of tectonic movements?
The rate and direction of tectonic movements can be measured by comparing the coordinates of the same GPS receiver over time. The coordinates are obtained using trilateration.
All materials I could ...
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Satellite’s Position and Path on 2D Map [closed]
When the ISS orbit the Earth, its path traced on a 2D Mercator Earth Map is similar to a sinusoidal wave. I am wondering is there any way to determine the trig function of the wave, knowing the ...
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How does one generate a formula(s) for an artificial satellite's location at time $t$ given a set of known locations at discrete times?
Given a set of spatio-temporal points in space {(Lat_1, Lon_1, Alt_1, Time_1), ... (Lat_n, Lon_n, Alt_n, Time_n)}, I need a function (i.e. a formula) that takes these points (or subset of points) as ...
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How fast would a rocket have to go to maintain in the earth orbit without falling down? And how frequent would rocket boosters be needed? [closed]
I was thinking how fast would a rocket have to go to maintain in the in earth orbit? I was thinking of the ISS going 7000kph with rocket boosters every 6 months. What is the most efficient way to ...
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Change in Path of a satellite on changing its velocity
When the speed of a Satellite travelling in a perfectly circular orbit is increased does the path of the satellite remain circular and the radius is increased OR does the path of the satellite follow ...
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How did the electronic components in Parker Solar probe responsible for controlling it and communicating with base station survive high temperatures?
The recent revelations by Nasa that their solar probe had been closer to the Sun by never before distances and aims at getting close to Sun by a mere 6.9 times radius of the Sun around year 2025. ...
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Can I please get the proofs for different trajectories of a satellite when projected at different velocities? [duplicate]
I recently came across a question about the trajectories of satellites, I have tried many resources for the proofs but couldn't find them.
For example, a satellite will have an elliptical orbit if (...
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How does the James Webb Space Telescope avoid stick/slip and creep problems when positioning its mirrors?
The JWST is now positioning its mirrors so they form a single image. How James Webb's Mirrors MUST Work To do this, each mirror must be positioned in 8 nanometer steps in 6 degrees of freedom. Here is ...
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Man pushes a satellite
A man M and a satellite S of comparable mass (say 5M) are revolving round the earth in a fixed orbit.
Now what will happen if man gives a strong jerk to the satellite in opposite direction to their ...
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How to visualize the frequency of a satellite?
For a satellite I know the period T and frequency f = 1/T. For instance, for an earth skimming satellite with period ...
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Could a large panel of LEDs be used for station keeping in earth orbit?
Hall effect and other ion thrusters require propellant to operate and thus have a limited usable lifespan in orbit.
In typical operational use, the force they produce is in the 25mN - 250mN range. It'...
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Accelerations of a Satellite Orbiting Elliptically about the Earth
I seem to be at a standstill on an orbital mechanics problem. My work right up until my roadblock is shown below.
Consider a satellite elliptically orbiting the Earth (the center of the Earth is ...
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Time dissemination in Solar System IAU expression (apparently) not matching General Relativity general result
I have a question about time dissemination around Earth on in the Solar system.
A standard expression for an Earth satellite a proper time shift w.r.t. Earth centered coordinate time (TCG), derived ...
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Determining orbital height of a satellite just by observing angular velocity
A few days ago I obervered a satellite with my telescope. But when I later looked at Stellarium (after adding all available satellite databases), there was no satellite passing the spot that I ...
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Roche limit and satellites orbiting each other
Does the Roche limit apply also to two satellites orbiting each other or only to individual satellites held together by gravity?
For example, I have a tungsten little ball (10 cm in diameter) around ...
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Time dilation inside International Space Station
SR tell us that inside ISS time is running slower than on the earth. But velocity is relative. We can choose to consider either ISS or earth to be at rest. An observer inside ISS sees the earth ...
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Where does the force tangential to Moon's orbit come from?
Not sure if I'm correct, but as far as I know, while moon is revolving around, it is unable to reach the Earth because the Earth's gravitational force isn't strong enough for that. This presumes that ...
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How to avoid Kessler syndrome with human made satellites? [closed]
It has been a year that I am dreaming to find a way to destroy a satellite in a clean way (push out of orbit or reentrance).
I first tought to use the momentum of laser to push a satellite out of ...
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Shadow Time for a Satellite on an Inclined Orbit
I am trying to calculate the shadow time for a satellite on an orbit that is inclined by some positive amount of degrees. I am able to calculate it for a non inlined orbit but i do not know how to go ...
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The accelerate from an elliptical orbit to a circular orbit
If there is a satellite and it is in an elliptical orbit. At the aphelion, it accelerates from its elliptical orbit to a circular orbit.
The thing that confuses me is that when the satellite is at ...
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Increasing the speed of satellite to raise an orbit
Suppose we have a satellite orbiting the Earth in an elliptical-closed orbit. When the satellite reaches the perigee, its velocity is increased in the cross-radial direction. According to all the ...
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