Questions tagged [low-earth-orbit]
Questions regarding Low Earth Orbit or LEO, which refers to orbits at an altitude between approximately 160 kilometers / 100 miles and 2,000 kilometers / 1,200 miles.
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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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Definition of "stable orbit"
I often struggle with the term "stable orbit" for objects in earths sphere of influence, since all real orbits are affected by disturbing forces.
Sentences like:
It is not possible to ...
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LEO Satellite Service / Coverage Time Calculation for a Ground User
I want to determine the time interval during which a ground user is in the coverage of a particular LEO satellite. I only have knowledge of the user's geographical location and the satellite's TLE (...
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GMAT LEO spacecraft simulation
I started using GMAT, I have to design an LEO of an AEOLUS Satellite and I have the TLE of the launching. My question is how do I plug the TLE numbers into the spacecraft section (Keplerian element ...
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Ground station : DVB-S2 TBS-6903 Receiver to communicate with a LEO Satellite
I am working on a project to develop a ground station that communicates with a LEO Satellite in X Band via the DVB-S2 communication standard using off-the-shelf components.
It appears that the TBS-...
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How much of the small (1 mm - 10 cm) LEO debris are electrically charged?
Upon investigation of Soliton based LEO debris detection, most research require that the debris is electrically charged. So I would like to know what is causing the debris to be charged and how much ...
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How much of what we see as “satellites” is space junk?
Ground observers using naked eyes see several LEO objects per minute under good observing conditions, and many times more with binoculars. These are usually referred to as “satellites”. Many are, ...
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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 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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Orbit prediction for satellites using the Kepler model
I would like to know how to model the motion of satellites in orbit using Keplerian, i.e. develop a simulation model that tracks paths of satellites using Keplerian orbits in Python?
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Higher density medium tube from sea level to space for travel
Is it theoretically possible to build a strong sealed tube from Earth's sea level all the way to Space, fill it with a medium (such as water) that has a higher density than humans. And then humans ...
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Understanding the difference between pointing knowledge, pointing accuracy and pointing stability?
In terms of specifications for satellite Attitude Determination And Control System (ADCS) hardware, my understanding is that pointing knowledge is for attitude determination, whereas pointing accuracy ...
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Negative elevation angle
What does it mean to have negative values of elevation angle from the low-Earth orbiting (LEO) satellite? Can the negative values of elevation angle be useful?
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Would the reflected sun's radiation melt ice in LEO?
If they tow a big chunk of ice to LEO, shielding from the Sun will be required. My question is, would they have to shield from Earth as well?
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Inter-satellite/Inter-platform communication requirements
I am studying Inter-satellite/Inter-platform links and would like to compute the link budget: Satellite-Satellite or HAP to HAP ( high altitude platform).
For my computation, I am looking for a ...
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TLE along track error to miss a contact opportunity in UHF
Update: (following @GregMiller's comment):
Lets suppose a spacecraft has performed a boost and not all ground stations received the update, lets suppose the difference between the pre and post ...
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Analyse the Doppler effect in non-GEO satellites: calculation of Doppler shift ( frequency)
I want to compute the Doppler frequency for LEO/MEO/GEO satellites. For the calculation I am using the following equations:
$$V= \sqrt{(G \cdot \frac{M}{R+h})}$$ - satellite speed. Height dependent
$...
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Minimum number of satellites to achieve 24 hour coverage at LEO for a single point
If I want to cover one single point on earth with 24 hour coverage using LEO satellites, how many are needed at minimum and what would be their orbit
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What would be the advantages and disadvantages of a LEO Earth observation satellite, carrying both Electro optical and SAR payload be?
An Indian startup, is trying to build a multi- payload satellite having both optical and SAR sensor on the same satellite. The look angles of the these payload are quite different and it is very ...
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Elevation angle for a non-GEO satellite
I want to calculate the elevation angle of a Non-GEO satellite with respect to a ground terminal. The information I have to solve this:
Instantaneous Longitude, Latitude, and Altitude of the non-GEO ...
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Equatorial LEO Satellites
Which satellites orbit in an equatorial LEO ($0^{\circ}$ inclination) around Earth? Or where can I find information regarding this that will give me the exact location of that satellite (longitude and ...
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I'm building a CubeSat for a short 8-day mission in LEO followed by a fairly quick reentry, what range of orbits to consider?
The goal of this CubeSat mission is to demonstrate CubeSat construction, operation, and communication in Low Earth orbit for 8 days or longer.
Why the short mission time? Because the mission lacks ...
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Polarization mismatch between a LEO satellite and ground terminal
Cross-polarization loss between a circularly polarized antenna and vertical or horizontal polarized antenna is known to be -3dB. This is one of the reasons why Circular Polarized antennas are ...
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Determining a suitable 'low orbit' for an arbitrary airless body
A while back, I asked this question here, dealing with finding a standard low orbit for a solar system body. The answer I received was mainly in the context of a body with atmosphere. This answer gave ...
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Space Debris? Gecko toes to the rescue?
Removing orbital debris in a safe, robust, and cost-effective manner is a long-standing challenge, having serious implications for LEO satellite safety and access to space.
Orbital rendezvous is ...
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Problem with ISS state vector (ECEF or ECI ?? rotating frame problem ?)
I have a serious problem with some satellite state vector I use. I got the cartesian coordinates of ISS (X,Y,Z) but do not know in which frame unfortunately. So I tried to plot them in 3D to check if ...
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Implemented analytical orbit propagator
Anybody knows about reliable open source implementation of analytical orbit propagator (for a generic orbit, given the initial state and not TLE)?
Possibly including up to J2 and drag also.
I have ...
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Draper Semianalytical Satellite Theory (DSST) C/C++ version
Anyone knows where one could find the Draper Semianalytical Satellite Theory (DSST) semi-analytical propagator code in C/C++?
I know Orekit includes the Java version inside its code.
An in general if ...
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Optimal numerical method to solve BVP for optimal low thrust control
I need to solve a boundary value problem (BVP) for an optimal control in case of low thrust trajectories optimization. I want to include the J2 perturbations to the Edelbaum solution (multiple ...
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What are the product terms shown here representing an orbit?
I can compute Kepler parameters from a given TLE using Skyfield. I am checking the satellite information from this website and the orbit is represented as
$$
546 \times 548 \text{ km} \times 53.1 \...
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Could a third stage be added to Starship?
SpaceX has predicted that Starship will be able to lift up to 150 tons to LEO. Could some of the payload that it will carry have a third stage? If so could that save another flight of Starship since ...
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Could it be more cost-effective to refuel with on the lunar south pole produced methalox instead of refueling methalox in LEO, on the way to Mars?
In the article Prominent volcanic source of volatiles in the south polar region of the Moon it is calculated that 8 x 109 kg $CO_2$ has been vented billions of years ago by pyroclastic events in the ...
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Revisit time estimation for a SAR constellation
I am studying satellite coverage analysis and I have read something about revisit time I did not understand.
you can increase and increase the number of satellites to further improve the revisit time, ...
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What does LMO mean?
I know that LEO means low Earth orbit. I thought that LMO would mean low Mars orbit, but my friend said it means low Mercury orbit. Does LMO mean low Mars orbit, low Mercury orbit, none of those or ...
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Weaponizing the Starlink constellation
Starlink aims at having tens of thousands of satellites in orbit in a few years. At any given point in time there will be a large number of satellites close by any inhabited places, including the ...
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Would satellites going into a rendez-vous show a difference in potential leading to an arc between the structures?
I'm researching into satellite rendez-vous. I know (NASA-HDBK-4006A) that in space (more precisely LEO) there is a plasma made up with electrons and atomic ions and a 'plasma potential'. I also learnt ...
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Significance of measure of dispersion in Orbit determination output
I am trying to understand the significance of specifying dispersion measure of 3 sigma or ½ sigma along with Orbit determination output. I am assuming a Space Craft in LEO sun-synchronous orbit of ...
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How long can the SpaceX Starlink satellites survive before they deorbit?
Like most Low Earth Orbits (LEOs), the Starlink satellites will eventually have their orbits decay and burn up in the Earth's atmosphere. How long, on average, will this take? I am assuming that there ...
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Draper Labs' Control Moment Gyroscope Spacesuit
Back in 2013/2014 Draper Laboratory announced that they were designing and testing a "spacesuit jetpack" that employed control moment gyroscopes (CMG) to allow astronauts to preform EVAs ...
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Is there any orbital launcher capable of removing the second stage from orbit after inserting the payload satellite into LEO?
The Space Shuttle was able to place a satellite into orbit and to return to Earth.
Is there any second stage that may deliver the payload satellite into LEO and do a deorbit burn after that using its ...
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Repeat ground track with 1 day repetition
I'm struggling with a doubt regarding repeating ground tracks (RGT). I've a satellite in a LEO circular orbit with a predefined non-polar inclination (64°) and I want to determine the needed semi-...
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How much energy would be required to launch a 10km x 10km x 10km cube into LEO?
I know this is a bit of a ridiculous scenario, I am just looking for a very conservative estimate as to how much force would be required to get something orders of magnitude bigger and more awkard ...
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Satellites - predominant apparent motion?
Recently, while foolin’ around with Stellarium, and checking out its simulation capabilities, I recorded some satellite activity.
Sped up ~30x, here are about 12 minutes of simulated sky on March 31, ...
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Using belt drive in LEO spacecraft?
I am designing a concept for a LEO spacecraft and need to transmit mechanical power (0.5Nm @200rpm rotation) over a distance (1-2ft). Chains or belts would be a natural choice for terrestrial ...
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How much will global warming increase the density of debris in LEO? What are predictions currently saying?
After about 08:00 in Scott Manley's hot off the press new release SpaceX Loses 40 Satellites To Solar Storm linked below he drifts away from the solar activity-...
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How much force is required to expedite reentry of space debris?
I'm trying to understand how much a small reduction in orbital velocity can affect the orbital decay rate of space debris. I understand that there are multiple factors to consider, such as debris in ...
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What is the average solar irradiation in low earth orbit?
I am trying to figure out how much power I can expect for a CubeSat in Low Earth Orbit. Is there some dataset or constant that describes the average rate of solar irradiation (per unit of area) in LEO?...
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What fraction of the Kapton thickness on the ISS' solar panels was likely eroded throughout their lifetime? Predictions? Measurements?
Background
@Tristan's answer to How are the silicon PV cells constructed in the ISS's solar panels? Are they as flexible as they appear here? informs us that Kapton is part of the "blanket" ...
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ISS propagation becomes much more accurate with reduced drag. Any ideas why?
I have currently been testing my implementation of a numerical propagator with the ISS. Without going into much details, the propagator considers Earth gravity (with the GGM03S model including zonal, ...
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Which Low-Earth Orbits Spend the Least Time With Access to Sunlight?
Regarding the (maybe completely absurd) possibility of powering a satellite via a ground-based laser, and perhaps (theoretically) also using that same laser to destroy any incoming projectiles or ...
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