Questions tagged [artificial-satellite]
Questions about objects in orbit which are human made, such as communications and GPS satellites, orbital observatories and space stations, and other man-made object in permanent or semi-permanent orbits around the Earth, other celestial objects, aside from the Sun, or even other satellites. Not to be confused with non-orbited man-made objects in space, that are usually referred to as "probes", or simply "spacecraft".
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Requirements for small spacecraft attitude determination and control system (ADCS) from the point of view of systems engineering and control [closed]
Are there currently any practical, well-founded basic requirements for small spacecraft orientation systems that can be used as a starting point for mission development?
Explanations: The main purpose ...
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How does the torque transfer from the reaction wheel to the satellite body occur?
Let's imagine a cubic satellite orbiting the Earth. The reaction wheels are located along the $x,y,z$ axes. Let's assume that the sum of the external forces is zero. Then the equation of motion along ...
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How do satellite trackers work when showing a "satellite"?
There are multiple sat trackers online where you can follow spacecraft orbiting Earth such as the ISS or the HST. I wonder how those trackers actually work when showing something near Earth, as the ...
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Are there any video/audio recordings of the launch of Sputnik 1?
I've been researching the launch of Sputnik 1, it is often renowned as the event that started the space age though I cannot find any confirmed videos of the launch or even a countdown/audio recording ...
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What's the theoretical dV of the SNAP-10A satellite?
SNAP-10A, launched in 1965, was the first nuclear reactor tested in orbit. It was intended to produce 500 watts of electricity for a year, but it only lasted 43 days; a voltage regulator in the ...
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Internet satellite constellation at 5,000km [closed]
Imm really disturbed by the large number of Starlink satellites. I know that they have to be like this to reduce latency. But perhaps a moderate increase in latency is tolerable if it leads to a ...
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Why would Starlink launch appear as a blurred line?
I believe that I recently saw a Starlink launch (details below in case I am mistaken); what puzzled me was that it appeared as a blurred, hazy line or streak. I watched it move across the sky and at ...
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Is the angular orbital velocity of a satellite in a circular orbit constant?
I know that the angular orbital velocity of a satellite in a circular orbit is $w_0=\frac{v}{r}$ but I want to know if the angular orbital velocity of a satellite in the circle orbit is constant. I ...
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How do satellites operate below their operating temperature?
As we all know, space is a vacuum and doesn't support "temperature" too well.
However, when a probe is placed away from a star, the temperature is quite enough to damage electronic ...
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Finding satellite visibility with ephemeris state vectors instead of TLE
I have been using Python excellent skyfield module to compute Earth satellite events from a given point (ie. visibility—rise, culmination, and set, as well as ...
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Mean motion as indication for satellite (evasion) maneuvers
I am interested in detecting satellite maneuvers, e.g., to avoid collissions.
As far as I understand the best publicly available data comes from TLEs although they have their own problems.
What is the ...
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What does "Common frequency offset" plot means in gnss raw measurements?
I'm using Google's MATLAB code to analyze raw gnss measurement made with gnsslogger android app. In plots, there is one in particular that I don't understand the meaning, which is "Common ...
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How to determine the number of Multi Layer Insulation layers for a satellite?
I've been learning about Multi Layer Insulation (MLI) blankets for spacecrafts. I'm trying to figure out how to estimate the number of MLI layers that will be required at a particular orbit.
MLI ...
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Why is this satellite's solar panel oscillating?
Watching this video 2024 solar eclipse shadow seen from space by satellites and space station
of a satellite capturing video footage of moon's shadow on Earth during eclipse.
The accelerated footage ...
user19132
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What could cause a satellite to tumble during operation?
Detumbling is a common problem and challenge for satellite operators during Launch and Early Orbit Phase (LEOP), with a common cause being a tip-off rate induced during separation with the launch ...
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Does the dawn-dusk orbit maintain the inclination with respect to the ecliptic plane?
I'm trying to understand the mechanics of sun-synchronous orbits, specifically the dawn-dusk orbit.
If I understand correctly, the RAAN rotates around the plane of reference of the Earth, which is the ...
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How to build an orbit propagator?
I am trying to build my own satellite orbit prapagator in MATLAB with RK4 integrator and force models added to the propagator to give the perturbed orbit in ECI frame. I am a bit confused and just ...
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Why didn't NASA launch communications relay satellites outside the asteroid belt to communicate easily with interstellar satellite?
I came across with nasa's voyager and other interstellar satellite, just thought that if they build a relay satellite which situated outside asteroid belt or nearby to Saturn & Jupiter, to ...
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Is there any satellite that uses LOX as oxidizer?
With Liquid Oxygen being used as an Oxidizer in Starship and some other rocket engines, I was curious if LOX was also used for propelling satellites as well.
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For using the acceleration due to drag formula, which coordinate frame should the satellite's position and velocity vectors be in?
I am working on simulating the space environment for a VLEO satellite. I am working on the atmosphere model where I am using density values from NRLMSISE00 model and plugging them into the drag ...
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Would tidal forces be strong enough to stabilize a configuration where one satellite is being used to tow another satellite?
The scenario that I'm contemplating is one in which there is a first "depleted satellite" that has run out of propellant and a second "rescue satellite" that is designed to rescue ...
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connecting two satellites [closed]
How strong would my bond have to be if I wanted to closely connect (30cm - 1m link) two satellites on the same orbit in LEO? (I can move the satellites however I want to have them close to each other)
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How do other satellite and ICBM clocks interact with GPS satellite clocks
I've read this answer about satellites synchronizing their clocks with the Earth frame with adjustments for special and general relativity for speed and gravity. There are some satellites and ICBMs ...
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How to design a Blowdown or Pressure Regulated pressurization system for a spacecraft?
I am trying to develop a simple tool to size a pressurization system for a spacecraft using either a blowdown pressurization system (BD) or a pressure regulated (PR) pressurization system. Though I ...
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sending a satellite in the right direction
I suspect that the required accuracy of satellite velocity direction is very high. This is especially the case for low earth orbits.
The radius of the earth is 6400 km. The altitude of a low earth ...
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Have there been any Spacewalks to free-flying satellites?
Talks of a new Hubble servicing mission have made me curious:
Has a spacewalk between a crewed craft and a free-flying satellite ever occurred?
As far as I am aware, the Shuttle visited satellites and ...
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Does a country need to announce the parameters of its newly launched satellite to the world?
I am wondering if there is any international organization regulating such things.
Possibly countries do not need to tell anything about their spy satellites, but should tell about their commercial ...
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Typical external temperature profile for a LEO satellite
I bumped into a question regarding LEO orbit.
Is an external temperature profile available in literature as a first approximation for thermal analysis? I bumped into articles mentioning that the ...
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Disposing of Obsolete Satellites by Propelling to the Sun
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 ...
Jim Elmore
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What is the feasibility of High Resolution (< 5m) Hyper spectral Imaging satellite?
Many companies are coming up with claim of less than 5m resolution of hyper spectral imagery, although the payloads of such caliber could be built, I have come to the understanding that SNR would be ...
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What does a "handover" really mean in satellite communications?
I am working on simulating a satellite constellation and I keep coming across the term "handover". My general understanding is that a handover is when a ground station switches its connected ...
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Which satellite is this very bright object? - part 2
A few weeks ago, I asked the same question about a bright object that I observed, initially thinking it wasn't Venus, but was told that it actually was Venus. Oops, fair enough. Here's another bright ...
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How to maintain minimum distance between satellites for duration of their orbits
I am working on a simulation in python that involves propagating hundreds of satellites over time. For simplicity, let's assume I have satellites at only a single inclination separated into multiple ...
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Which satellite is this very bright object?
For the past few years, I've been spotting this "star" periodically in the night sky. Except it's not a star because it doesn't twinkle. And I don't think it's Venus, because I've observed ...
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How I can find the angular orbital velocity of satellite in circle orbit?
I know that we have the angular orbital velocity of a satellite in circle orbit as $w_0=\frac{v}{r}$, but I want another way to find out the angular orbital velocity of a satellite in the circle orbit....
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What network does the Chandra X-ray Observatory satellite use to communicate with Earth while staying in its orbit?
From a NASA fun facts website How do satellites communicate?:
How do satellites communicate?
Satellites communicate by using radio waves to send signals to the
antennas on the Earth. The antennas ...
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How to access satellite & debris data categorised by intended purpose?
I'm working on an art project which requires satellite data (active, inactive, as well as debris), so I was on Space Track. Does the NORAD ID or some other field help retrieve information about the ...
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how to procure a Launch vehicle for injecting a cubesat into LEO at LOW COST?
Me and my team are working on sending Cubesats just beyond the Karmann line. For which we obviously need a launch vehicle and would like to procure one or if possible build one. If any aerospace ...
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Do all artificial satellites have engines?
Novice question. A few days ago I watched a TV documentary about Virgin Orbit’s failed mission earlier this year to send satellites into orbit from Spaceport Cornwall. One of the satellites shown ...
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If the largest spy satellites could take pictures, how detailed would they be?
This question is inspired by the NRO's Orion Satellites. These are surveillance satellites placed near geostationary altitude that measure radio emissions.
Importantly, they have been described as the ...
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Difference Result of Numerical Satellite Propagator
Currently, I am trying to build a numerical propagator platform for satellite that accommodates for all kinds of perturbation. So, for validation purpose, I compare the result of my own program and ...
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How are starlink satellites deployed?
I'm not a science guy, but I did some research and I gathered that the rocket's upper stage spins before releasing the satellites stack in such a way that each satellite is given a slightly different ...
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Sattelite position from TLE
How to get satellite position from TLE without any libraries? Because in Processing there is no libraries like SGP4.
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Predicting the ground path of a satellite's shadow
Given the orbital parameters of a satellite, how can I predict the ground path of its shadow? (The path from where it will appear to transit the Sun).
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Is the full GPS constellation a Walker Delta constellation?
Through the extremely rigorous method of looking at the animation on Wikipedia's article about GPS, if this does indeed accurately represent GPS satellite orbits, then it looks like not all of the ...
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Maximum and minimum surface temperatures of a satellite in GEO?
Just as the title, how could one find out, or simply estimate the maximum and minimum likely surface temperatures of a satellite orbiting in GEO.
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How do engineers measure satellite drag, and how do they track it over time?
I’ve been slowly getting myself familiar with astrodynamics and understanding satellite orbits. I’m familiarizing myself with the concept of drag experienced by the satellites. I am curious about how ...
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Given historical TLE’s, how do I determine the path/orbit/LLA of a satellite for a given historical period?
Im trying to get the historical Lon/Lat/Alt of a starlink satellite. I'm using TLE's from space-track and Skyfield to calculate latitude, longitude and altitude of satellites for a given date range. ...
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How can I get a list of GNSS satellites in view for a given date/time
I need to generate a list of which satellites were in view at a given date/time. I'm specifically interested in the Galileo constellation of GNSS satellites, and I'd like to get a list of when each ...
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How do I calculate the maximum northern and southern latitude a LEO satellite can image?
How do I calculate the maximum northern and southern latitude a LEO satellite can image? What parameters would I need?
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