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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What are the temperatures of objects in Low Earth Orbit (LEO)?
What is the temperature of objects in Low Earth Orbit?
Consider LEO to be 600km to 800km.
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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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Given an equation of an elliptical orbit, is it possible to find satellite´s speed at a certain point?
As the heading says: given an equation of an elliptical orbit, is it possible to find satellite´s speed at a certain point? I'm playing a bit with simulations of planets and satellites in the solar ...
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Why are GPS transmitting signals made so weak?
Twice this year, my car's GPS receiver got totally lost. It seemed the cause of this was heavy cloud, (because I can't think of any other reason), and the GPS stayed in "Recalculating" mode, until ...
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Orbital speed in an elliptic orbit [duplicate]
I want to have a general solution for calculating orbits. Wikipedia says how to put object on circle orbit. We must give it speed $v_1 = \sqrt{g(h_o +R)} $ Where $h_o$ - is the orbit height, and $R$ -...
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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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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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Why is a projectile trajectory parabolic while that of a satellite elliptic?
I understand that the parabolic trajectory is an approximation of a more elliptical trajectory, since acceleration due to gravity is taken to be a constant for a projectile. However I'm intrigued to ...
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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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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 relativity is symmetric, do the satellites in the GPS system see the earthbound clocks as running slow due to relativistic time dilation?
If relativity is symmetric, do the satellites in the GPS system see the earthbound clocks as running slow due to relativistic time dilation?
How much slower does the satellite see the earthbound ...
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Getting first and second time derivative of mean motion of spacecraft - without TLE?
The Celestrak website provides information on reading the TLE ( Two-Line Element Set ) format. In Line 1, Column 34-43 & 45-52 give information about ...
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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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Can a satellite have one axis horizontal to its host, and spin about that axis?
Apologies if I'm not getting the terminology quite right with this question. Some natural satellites (e.g., most planets) have orbital position and axial tilt disconnected; that is, they're rotating ...
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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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Acceleration due to gravity?
I was looking into orbitals and found something I haven't been able to understand.
http://www.math.ubc.ca/~cass/courses/m309-01a/hunter/satelliteOrbits.html
There is a part on the page which states ...
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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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Calculate orbital speed of object around earth (SpaceX data)
I am just reading SpaceX rocket data satisfies elementary Hohmann transfer formula, a paper of how to use SpaceX telemetry data in educational physics.
In particular the paper contains the following ...
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Orbital Mechanics - How does space debris damage the ISS?
This question is rather self explanatory so I'll keep I succynct.
A while back Tim Peake photographed a small crack in the cupola of the ISS, which was reportably a paint fleck that collided with ...
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Relative angular velocity of a referential system translating and rotating
I intend to determine the angular velocity of a referential system, $S$, translating and rotating in relation to an inertial referential, $S_o$.
I need to know this concept to determine, for example, ...
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How to calculate orbital eccentricity from the ratio of satellites' velocities?
I have a problem with working out how to calculate the orbital eccentricity from the ratio of two satellites' linear velocities. We know that two satellites encircles the Earth in two elliptical ...
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Acceleration vector for an object moving in a elliptic trajectory
I am interested in deriving what the radial and tangential components of the acceleration vector should be for an object following an elliptical trajectory centered on the origin, in which the ...
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Signal strength drop-off from a geosynchronous satellite as a function of angular pointing error
If we have a compact antenna used to communicate with a satellite in geosynchronous orbit somewhere between the $K_u$ and $K_a$ bands of the spectrum (for high broadband applications where we can't ...
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If most satellites in orbit were destroyed from debris, would we ever be able to recover?
Suppose enough satellites were destroyed in orbit to cause so much debris from the explosions that a chain reaction destroying other satellites took over to generating more and more debris (even ...
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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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Collision of two satellites
In a theoretical situation in which two identical satellites travelling around the Earth in opposite directions collided head on so that there velocities relative to the earth both became 0, would ...
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What is the limit to how many satellites can orbit the earth?
I would like to know how many satellites are physically able to be in place, at the same time, orbiting the earth. Lets ignore which Nations need or use the most satellites (area in space above them) ...
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Why do satellites orbit around the centre of a planet?
Why can satellites not orbit around the North or South Pole, instead of orbiting about the centre of the earth?
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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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In what way has GPS had an impact on our understanding of physics?
I've been reading about the effects GPS has had on our society with the February launch of a IIF Satellite and I was wondering if launching GPS satellites and the actual GPS satellites have lead to ...
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Calculating speed of satellite in vacuum?
Satellite speed is $35\ \mathrm{km/s}$ after burn for $500\ \mathrm{ sec}$ and after some days or months this speed is reduced automatically $34$, $33$, $32$ respectively.
Questions:
How the ...
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Can a satellite remain directly over a city?
Is it possible to put an artificial satellite into an orbit in such a way that it will always remain direct over a city (I mean at any specific place)?
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Does Earth's rotation affect the orbital velocity of its satellites?
We all know about the spin of black holes. That spin and of course it's gravity determines the minimum distance a star can orbit the black hole with a min orbital velocity.
Do we see similar result? ...
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Total work done on a satellite
I have a question about the concept of work in relation to conservative and non-conservative forces. Is Total work done $=$ change in kinetic energy or change in total energy $?$
This question arose ...
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Planetary motion considering natural satellite
Using Kepler's laws of gravitation we can determine the time period of a planet revolving around the sun.
However, this excludes the gravitational effect due to satelite(s) orbiting around the planet. ...
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Can a satellite park between the Earth and Sun?
If you put a satellite at Geostat altitude travelling the wrong way, will it remain between the Earth and Sun?
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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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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 do satellites accelerate in space with thrusters?
In my space exploration topic we are learning about satellites. We need to know a bit about thrusters and what they do. However I don’t know how the thrusters accelerate the satellite in space. It ...
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Why aren't orbits transferred at the perigee?
In example 10.6 titled "Satellite Orbit Transfer 1" of Kleppner and Kolenkow the author says
The most energy-efficient way to put a satellite into circular orbit
is to launch it into an ...
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What is orbit that could place satellite to be always under the Sun?
I just thinking that, if we could place satellite to orbit earth in opposite direction of earth rotation, inverse of geostationary orbit. If we carefully choose a speed to sync with earth rotation, it ...
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Why do satellites settle into elliptical orbits?
When a satellite in a circular orbit around a planet is given a sudden speed boost, it tends to settle into an elliptical orbit, with the planet at one focus.
Why does it settle into an elliptical ...
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What is the difference between kinematically non-rotating and dynamically non-rotating reference frames?
Well the question in the title basically sums everything up but to put it in more context...
I am trying to wrap my head around the relativistic Geocentric Celestial Reference System (GCRS). Reading ...
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Principle of launching satellites into orbit
I was reading in a book about the basic concept of launching satellites into orbit. I came across a paragraph saying,
If we take a body high above the surface of the earth, and then project it with ...
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Does the International Space Station always travels in the same path?
From the 3d visualization http://www.satflare.com/track.asp?q=25544#TOP (the right image with the red line indication the path of the ISS) it looks like always the ISS takes the same path. Is it the ...
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Martian space elevator from the vulcano Olympus Mon to the moon Phobos?
In my fascinating imagination, I am seeing a space elevator from the vulcano Olympus Mon to the moon Phobos. Phobos also seems to keep spaceships - while a smaller shuttle attaches itself to the ...
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How does acceleration affect the orbit?
I want to know what roughly happens if we hit an orbiting body a little. And how is it possible that most of the objects have seemingly circular orbits around. How do they stabilize? I ask because it ...
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Can we make a space elevator/lift?
Is it possible to connect a long rope (excluding the danger of it's breaking) to a geostationary space station and use it to transport food and other necessary item's to the station and then ...
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How does my car acquire satellite signal? [closed]
I just got XM radio again after a brief period without it. A customer service rep said that the satellite needs to beam my signal to me in a six minute time window. How exactly does this happen? How ...
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Will a satellite escape from the bounds of Earth's gravity if its orbital velocity is increased to escape velocity?
If orbital velocity $(v=\omega r)$ is increased to escape velocity at that certain orbit, will it move to infinity? I know that it will skid from that orbit as vehicles do when their velocity is more ...
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