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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Problem with relative magnetic reference frames [on hold]

I came across this problem a while ago and I'd like to solve it, but I'm not even sure where to start. I know I need to use the magnetic reference frame to its angular rate of change, then use it to ...
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How does a single satellite like the upcoming BIOMASS use interferometry?

The future satellite BIOMASS, from the ESA, will supposedly use p-band frequency interferometry to detect changes in forests. By itself? How?
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Satellites orbiting around any planet's [on hold]

Suppose a satellite is revolving around a planet with radius r. Now if we increase the value of r then the angular velocity and kinetic energy will decrease, but the total energy & potential ...
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Escape velocity and orbital velocity confusion

If orbital velocity is reduced when we want to put a satellite in a higher orbit, and if to achieve a lower orbit we need to increase it's velocity, then how come by increasing the speed of the ...
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Inextensible filament structure in gravitational field

Let $\gamma$ be a curve lying in a gravitational field with each point moving as an independent point mass. Formally, \begin{equation} \partial^2_t \gamma(u, t) = -\nabla U(\gamma(u, t)), \end{...
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Time dilation in satellites [duplicate]

Is the time dilation suffered by clocks in GPS satellites accurate to what is predicted by special relativity? By "accurate" I mean to ask if the numerical answer given by relativity equations match ...
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Satellite image anomaly

This is a satellite image of somewhere in West Texas: See the localized Red-Green-Blue feature on the road? What could have caused this?
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Geosynchronous satellites with polar orbit?

I know that satellites can go in polar orbits, but as far as I have read, this is only done by LEO satellites. I think it is possible to have geosynchronous satellites with polar orbits (near polar), ...
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Astronauts in spacecraft, they have to circle the earth many times a day, do they also have the illusion of the moon?

Astronauts in spacecraft, they have to circle the earth many times a day, do they also have the illusion of the moon? I don't think they have, because according to the theory, the illusion of the moon ...
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Satallite orbiting the earth [closed]

I need help understanding a question from my physics book. It goes like this: a communications firm wants to place a satellite in orbit so that it is always directly above the earth’s 45th ...
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How does light transfer momentum to a solar sail?

Last month the Planetary Society launched Solar Sail 2. After reading about it a bit I found that its a type of payload carrier that works on the principle of transfer of momentum from light. ...
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Sunlight on an object

I'm not entirely sure how I should be phrasing this question, but it's part of a project I'm working on. It's all about finding reflectivity by way of a telescope. We figured the first way to proceed ...
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Time dilation in a geosynchronous orbit

since gravity slows time, and velocity slows time, would observer A on the equator directly under observer B in a geosynchronous orbit experience time at the same rate? Time would slow on the surface ...
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How does the orbital radius affects the orbital velocity

I have a question says that "If the orbital radius of a satellite increase four times the orbital velocity will be ..." and the answer is that the velocity will be doubled !! We studied that orbital ...
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Change of orbit with tangential impulse

I see a similar question: Change of orbit with a radial impulse. The answer to that question seems fine to me. In the answer, mention is made of this similar question, but it is not fully treated. ...
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Trajectory of a satellite whose velocity is less than circular orbital velocity? [closed]

If the velocity of the satellite orbiting around a planet is reduced somehow...then what would it's trajectory looks like spiral(1) or elliptical(2) Or Does it depends on the  velocity it has(less ...
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Why aren't satellites disintegrated even though they orbit earth within earth's Roche Limits?

I was wondering about the Roche limit and its effects on satellites. Why aren't artificial satellites ripped apart by gravitational tidal forces of the earth? I think it's due to the satellites being ...
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Can satellites stay in orbit when the Earth is being accelerated?

In a TV show I'm watching, the people of Earth have decided to leave the solar system, and take Earth with them, so they've built a large number of powerful rocket engines on one side of the Earth (as ...
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Can we build a superconductor on the Moon and beam energy where needed? [closed]

Should we not build a superconductor facility on the moon ? We find a spot where the rays of the sun don’t provide heat. This should enable a superconductivity facility to operate due to the low ...
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Difference between Critical and orbital velocity

What is the difference between orbital and critical velocity of satallite ? I have read that critical velocity is constant value and it does not depend upon altitude. It only gives the velocity of ...
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Kepler's 3rd law: ratios don't fit data

I have been looking at satellite orbits around the earth, or any object around any planet in fact, and am trying to find the orbital radius, or semi major length of a given satellite. Kepler's third ...
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Kinematics and dynamics of a crashing satellite

A satellite in low, circular orbit around the Earth experiences drag (friction) and slowly spirals into Earth's atmosphere. It then enters the Earth's atmosphere, heats up catastrophically and burns ...
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Friction and satellites

There was this question we did in class. There is a satellite orbiting the Earth. It runs into some particles, and due to friction, the satellite loses speed. We were asked to predict what will happen ...
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How do microwaves communicate with satellites?

If microwaves only penetrate up to a few cm of food in a household appliance before being absorbed and transferring energy to water molecules, than how are microwaves able to communicate through long ...
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Number of GPS satellites required to give 100% coverage

I am a Belgian school student in sixth grade of secondary school (the Belgian equivalent of High school). Together with two class mates we were assigned to write some kind of essay about the Global ...
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Compute a model, based on the satellite velocity at 300 km orbit

I wanna test a special sensor which will be the payload of a satellite. For this, I need to fix a camera (with the sensor inside) at a distance h from a rotative cylinder (radius: r) to model a ...
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Size Reduction in Satellite Television Dishes

I don't know very much about Parabolic Antennas, but I was wondering, What is exactly the purpose of some Satellite Dishes installed in the roof of some houses that are very big compared with ...
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Orbits of satellites

For a satellite orbiting the earth, if there is only gravitational force acting on the satellite, does it mean it can only orbit the earth around the equator or through north and south poles? (only in ...
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Duration of Satellite orbit in the shadow of the Earth (elliptical orbit)

This question here calculated the time a satellite was in the shadow of the earth for a circular orbit. I was wondering if there was a way to do the same thing for an elliptical orbit.
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Orbit such that distance from Earth is always the same as distance from Mars

Would it be possible to place a satellite into an orbit such that its distance from Earth and Mars always remained the same? That is the distance between the satellite and Earth and the satellite and ...
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How come planets with different masses can orbit at the same velocity at the same altitudes?

Angular momentum is equal to r × p and angular momentum is also what gives planets with lower orbits a higher speed (because angular momentum is conserved). So as r decreases either m or v (p=mv) has ...
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gravitation (kinetic energy and angular momentum)

When a satellite in a circular orbit around the earth enters the atmospheric region it encounters small air resistance to its motion. then (1) kinetic energy increases (2) angular momentum decreases ...
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Experimental considerations for measuring the gravitational constant/effects, with two large (1000kg) masses orbiting each other? [closed]

So @uhoh, wanting to get some experimental data to verify Limits on non-Newtonian gravity at length scales larger than 1 meter?, proposed an experiment: Place two large (1000kg) spherical masses in ...
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If a satellite moves towards Earth, is negative work done against the force of gravity?

A bit confused here - if a satellite approaches Earth, its displacement is in the same direction as the gravitational force (towards the centre of rotation). Therefore, gravity is doing positive work? ...
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Do comets and meteors attract artificial satellites while passing by?

What will be effect on artificial satellites when comets or meteors come close or pass by?
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Bad value for sphere of influence with Venus [closed]

I would like to get value of sphere of influence than Wikipedia for Venus: on https://en.wikipedia.org/wiki/Sphere_of_influence_%28astrodynamics%29 It is indicated for Venus: $S_{\text{OI}}=0.616\,\...
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Sci-fi ships falling on planets

I hope the question is suitable for this forum.... Watching Star Trek: The Next Generation, I have found at least a couple cases where a navigation malfunction on a shuttle makes it fall towards the ...
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Satellite radiance measurements in spectral regions

Q: A satellite measures longwave radiation emerging from a planet with uniform surface temperature T1 and uniform atmospheric temperature T2. What values of radiance does the satellite measure in the ...
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Rotational movement of satellite in orbit

I would like to know how a satellite rotates around the Earth in terms of rotational movement. If it matters I'm interested in the helio-synchronous case -where the satellite is always visible from ...
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How is Geo Stationary Rocket placed exactly above the Location after Launch

My Question is bit deeper on the Satellite been put into orbit of GEO . Recently ISRO Launch GSLV Mark 3 to put into GSO . After the Rocket is launched and reached the Perigee ( 190 km ) the ...
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Will space junk handle itself to an extent?

So suppose that two satellites traveling in opposite directions collide and some bolts are hurdled at higher speeds than either of the bodies were traveling before. Since the junk is traveling at a ...
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How would the path of a satellite be affected by the gravitational constant decreasing? [closed]

An artificial satellite is moving around the surface of earth. If the magnitude of the gravitational constant starts decreasing at a constant rate, then what would the effect on the path of the ...
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A man on much faster spinning Earth decides to jump

Imagine that the Earth is spinning much faster than real situation and a man on the Earth's surface feels weightless. Suddenly the man decides to jump vertically with respect to the Earth. What will ...
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Electron distribution in Low Earth Orbit

I have been searching online for some kind of pdf function that describes the charged electron distribution in Low Earth Orbit in regards to their energies. Any ideas on whether something like that ...
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How does a satellite take pictures when the surface seems to be always cloudy/white?

I've just opened ISS video on youtube for the first time, and I must say I'm underwhelmed. There are no oceans/landforms. It's all white everywhere. I'm a bit confused how the satellites can take ...
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What is the orbit of SDO (solar dynamics observatory)? How does it takes images of Sun non-stop?

There is a orbital diagram given in sdo website https://sdo.gsfc.nasa.gov/ It takes images of sun 24hr.
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Gravitation question

I’d like to ask the following doubt that came to me after some exercises: Is it possibile to exactly establish,given a satellite orbiting Earth with a certain $\vec v_{0}$ and distance $\vec R_{1}$ ...
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What happens if the gravitational force on a satellite is greater than the centripetal force needed to keep it in circular motion?

Will the satellite continue to orbit the Earth, albeit not in a circle? Why? I would greatly appreciate it if someone could help me address this query. :) Also, I think someone asked a similar ...
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Total Energy of the ISS orbiting the Earth [duplicate]

I had a bit of confusion earlier about a discussion in astrophysics. I was reading that the ISS orbits the earth at $8 kms^{-1}$ but then when I calculated the total energy that the ISS had, I was ...
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Space Elevator - Could We Do It?

'Elevator to Space' or 'Death-o-Swing'? During one of my ever increasing day-dreams; I remembered something I heard in respect to a theoretical 'Elevator to Space' and I was wondering what you guys ...