Questions tagged [orbit]
Questions regarding the mechanics or attributes of objects falling 'around' other objects, thereby orbiting them.
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How do "halo orbits" save on propellent (delta-v)?
I am trying to understand what advantage the satellite's 'Halo Orbit' has compared to LEO or Geostationary orbits.
"Lagrange points have proven to be very useful indeed since a spacecraft can be ...
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STK: How to create an access report between an antenna and moon? [closed]
I am looking at how to go about designing an access/visibility report between a ground stations on Earth and the moon. I would like to have the coverage run for a couple of years and outline on the ...
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What is the relationship between the radius of the Hill sphere and escape velocity?
I'm currently working on a video game that will make use of a heavily simplified patched-conic model of the Solar System.
I was wondering about some discrepancies between my own calculations as well ...
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How much of a rocket energy is needed to overcome aerodynamic drag?
this question
How much of a rocket's energy is used to achieve altitude vs horizontal velocity? addresses the energy split of kinetic vs. potential energy to get to space - and to stay there.
We ...
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Does every celestial body orbits something? [closed]
Pretty much the title is the question. Lets take the massive blackhole of our milky way does this black hole orbit something?
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A black cube 1 mile per side appears in geosynchronous orbit around the earth. Who would spot it and how would they do it? How easy would it be?
This is not intended to be a math question, so much as an understanding of how the current technology and techniques would view this problem.
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Why is 51.8° inclination standard for Soyuz?
Soyuz flights are mostly around 51.8° inclination, and the Soyuz manual gives this as a reference value. Why is 51.8° the standard inclination? That's not the latitude of Baikonur, and I couldn't find ...
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How can I calculate GPS satellite's Latitude and Longitude if I have the elevation and the azimuth
Please tell me how I can calculate a GPS satellite's latitude and longitude if I have the elevation and the azimuth angles.
I am using a septentrio GPS receiver.
Thanks
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What is the simplest rocket design that can reach orbit
I am curious on what the simplest possible rocket design that have been proposed which could reach orbit.
My first thoughts would be earlier rockets like the Atlas LV-3B, but then I consider the ...
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Could we by ordinary mining activities, affect the Lunar orbit?
In The Time Machine (Guy Pearce version), they manage to literally break up the Earth's moon with obviously disastrous results and I believe they were just building underground structures.
I am ...
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AU Semimajor axis accuracy
I have used Kepler's 3rd law to calculate the Semi-Major axis of the Earth I have given it the mass of the objects i.e. the sun (1 solar mass) and the Earth and time taken to orbit (365 days, 6 hours, ...
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Using 2023 technology, how low can a satellite orbit earth?
With the technology available today, 01-01-2023, what is the lowest altitude at which we can orbit a satellite around earth?
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Eccentricity changes of an orbit during out-of-plane burns
I am learning about Space exploration and I have the following question:
Does the eccentricity of the orbit remain unchanged during a manoeuvre that is perpendicular to the orbital plane?
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Is the critical inclination the same on every planet in the solar system?
I am learning about Space exploration.
Is the critical inclination the same on every planet (in the solar system) or does it depend on the planet?
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GMAT Get States of Propagation
I am failing with the most simple thing ever:
I want to store the SC states of a Propagation over 1 day inside an array!
So the basic script would look like this:
...
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Delta-V vs Time equation for interplanetary transfers
I'm working on a project for my high school math class and my research question is about time vs delta-v budgets for an interplanetary transfer (e.g. earth to mars). I understand this is a relatively ...
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How to find the SMA starting from a given repetition factor?
I need a help for an orbit design problem.
My constraint is that the height is 480 km, the repetition factor has to be Q = 245/16 and the orbit must be sun-synchronous. I would like to find the SMA ...
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GMAT Orbit View with Spacecraft at centre
Is it possible to have an orbit view with the camera always centred on the spacecraft?
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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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Major axis larger than total of apogee and perigee?
I am trying to calculate the apogee and perigee using the orbital elements. I am checking my results against CALSPHERE 1 (https://www.n2yo.com/satellite/?s=900).
I am getting 7363599.5m as the semi ...
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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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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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How to calculate Local Time of Ascending Node (LTAN)
I have a time series of satellite position, $\mathbf{r}(t_i) = (r_i,\theta_i,\phi_i)$ representing geocentric radius, colatitude and longtiude at universal times $t_i$. I want to compute the Local ...
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Questions about Orbital Propagation
I am a beginner in the field of aerospace. Recently, I wanted to use the extended Kalman filter to improve the orbit.
My idea is to use TLE data as observations values, the ...
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How many collisions are possible to eradicate all already existing satellites? [closed]
If earth lost all contact with satellites, how many collisions would it take to be left with 0 satellites orbiting in their normal path?
Deep-space objects are not considered like James Web Telescope.
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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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How did the Lunar module reached orbit speed?
How does the lunar module of Apollo 11 reached an orbit speed of 1600 meter/second in order to rejoin the CSM (Command/Service Module)?
Additional question, Where are the Oxygen & Fuel tanks of ...
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GN&C and more examples for 42 NASA tool
Anyone knows where to find some further examples about 42 applications and examples, mainly relative to GN&C and small satellite Earth missions ( also constellations in case...)?
In the repo ...
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Is a geosynchronous (SSO-like) polar orbit around the Moon possible? [duplicate]
Imagine the equivalent of a sun-synchronous Earth orbit, just substituting the Moon for Earth and Earth for Sun. Such an orbit would have to have the following properties:
It would be a polar or near-...
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What is the distance between Mars and the lagrange point L2 Mars Sun? [duplicate]
I am writing a science fiction novel that is more soft that hard sci fi but I would like to know at least an estimat of the distances between L2 Mars Sun and Mars. I know that asking for an exact ...
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Keplerian Orbital Elements to Cartesian Coordinates issue with inclination, and possibly other stuff
this is the first time I am asking for help on this site, so if I format badly, or need to add/change something, let me know.
I am currently trying to make a game using python (python powered board ...
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What military satellites are passing over Antarctica
I need to know what satellites pass over the South Pole (Antarctica) especially military.
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How can I get longitude of ascending node from satellite TLEs with Right Ascension of Ascending Node (RAAN)?
As the title says, the TLEs contains RAAN, from which I want to get the longitude of ascending node, as defined in the STK help file as shown in the figure. Is there an open source tool for python to ...
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How to calculate earth's precession using JPL Horizons System?
I'm new to JPL Horizons and understanding how to use the tool efficiently.
I'm looking to extract earth's precession data and understand where we are in the current cycle. I understand we progress 1 ...
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What size are the typical keep-inside boxes of geostationary telco satellites?
Geo sats need station-keeping and the size of their keep-inside box is a design parameter. A smaller box implies more manoeuvres to stay inside the box. All depending on the various orbit ...
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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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Will Roadster ever encounter Mars?
During it first closest approach to Mars, it was a mere 5 million miles away from the red planet. According to observer.com, it's ultimate fate will be to crash into the Earth or Venus. However, since ...
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Where do I find ECEF coordinates of a satellite?
I am taking a university course named 'satellite navigation' as a part of my master degree in aerospace engineering. For the exam we are required to elaborate the coordinates of a LEO satellite (it ...
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Why is my C++ code for an orbit propagator wrong?
I tried making an orbit propagator C++ code. Its values seem to be propagating evenly but still I get a straight line orbit instead of an elliptical one. Why?
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How far is the solar system's center of mass from the sun? [duplicate]
We often say that the planets orbit the sun. But, in reality, they orbit the solar system's collective center of mass. How far is that point from the center of the sun?
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How do I correctly convert State Vectors to Orbital Elements to State Vectors at t (sec since epoch) in 2D?
I am following Rene Schwarz' formulas and I've verified my calculations work using the converter by Tony Dunn.
State Vectors to Orbital Elements
Orbital Elements to State Vectors
Convert between ...
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Is escape from earth, hyperbolic in reality?
I have been reading on orbital mechanics and its strewn everywhere that beyond the escape velocity from any orbit around the earth, the trajectory is a hyperbola that approaches V_infinity and with ...
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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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Were analog cameras been used in orbital space during an EVA after Apollo?
Analog cameras have been used intensively on the Moon and inside orbital space stations or ships.
Were analog cameras ever used during an EVA outside Spacelab, Mir, ISS or Space Shuttle? In zero ...
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What is the furthest from Earth that a military spacecraft is thought to have been intentionally deployed or moved to?
Space.com's Space Force plans to send a patrol probe out past the moon includes a quote from the new AFResearchLab video Cislunar Highway Patrol System (CHPS).
"Until now, the United States ...
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How can I find the true anomaly of satellites in elliptic orbits?
I want to find the true anomaly of satellites in elliptic orbits. How can I do that with following
information about elliptic orbit:
Altitude, km 543.8832
Period, sec 6114
Eccentricity 0.0727
Semi-...
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What type of galactic orbit will the Voyager probes have?
I know that they will eventually get close (within 10,000 light years) of our solar system, but will the orbit be circular or elliptical, around how much eccentricity, what would be a reasonable ...
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What's the highest latitude for a human spaceflight?
There are obviously many satellites in polar orbits or in orbits that extend to very high latitudes. There are obvious reasons to do this in terms of Earth observations, but there is probabably much ...
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Could astronauts jump from a spaceship onto a spacestation and how would it be like if yes?
I saw it happen in the videogame Alien:Isolation but not sure how realistic it was. I need help understanding some orbital mechanics for a sci-fi story that I am trying to write.
The scenario I ...
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How did India get to the Mars?
A few years back ISRO sent their orbiter to the Mars, It is known to be the biggest feat achieved by Indian Space Research Organization over the years.
It special because ISRO manage to pull this out ...
