Questions tagged [orbit]
Questions regarding the mechanics or attributes of objects falling 'around' other objects, thereby orbiting them.
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Vis-Viva equation applied to Earth
We know that the Vis-Viva equation is given by:
$v=\sqrt{G M\left(\frac{2}{r}-\frac{1}{a}\right)}$
If I plug-in the values for Earth (the mass is obviously that of the Sun):
$G=6.6743 \times 10^{-11} \...
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Equivalent Vis-Viva equation but for acceleration
I know that thanks to the Vis-Viva equation, knowing the elliptic parameter of a celestial orbiting object we can get its speed on any point of the orbit.
But what about the acceleration? Is there an ...
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In circle orbit, give a delta V to a satellite, how to find final orbit altitude?
I think this is a very very simple question for me, but unfortunately I cant solve it...
A satellite is orbiting in a circular path at an altitude of 600
kilometers. If the satellite is capable of ...
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Converting Keplerian Orbital Elements into 2D State Vectors in Unity C#
I have done an extensive amount of research into this topic, but am really struggling to implement the math necessary to pull this off correctly.
Just for some context: I'm trying to create a semi-...
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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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Would orbital ring platforms affect the orbit of a planet?
If we built an orbiting platform of sufficient mass (let's say, made from harvested asteroids) that was anchored at both poles of the planet it surrounded, would such an addition to the planet's mass ...
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Escaping Earth - how could one attempt to find the best solution to this trajectory optimization problem in practice?
If there is a satellite in low Earth orbit, with a limited delta-v budget (but high enough to escape Earth) and limited delta-v-rate (thrust), how could one find an acceleration schedule and ...
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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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Chemical Problems When Encountering Thin Atmospheric Worlds
Bodies such as Enceladus, Mercury, and Triton, etc... have thin (and often temporary) atmospheres.
When probes or landers encounter the chemicals in such atmospheres in low orbits/landings, they may ...
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Satellite Surface Temperature in Orbit
I am trying to calculate the satellite surface temperature in Orbit for Thermal Tests of our satellite.
Referring "Space Vehicle Design, D.Griffin, Ch.9, the equations of heat transfer on the ...
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In MATLAB, Computing a new TLE/orbit following a delta-v impulse?
I have already worked on this project for a week, and I still can not solve this problem by myself. How can I update data for the SGP4 OrbitPropagator in Matlab's ...
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Why Euclid's orbit is not like Gaia but like JWST?
Euclid, Gaia and JWST are all orbiting Lagrange Point L2. Why is Euclid's orbit similar to JWST but not Gaia's, why is Gaia's orbit different than Euclid and JWST ?
Orbits are shown here for example:
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Would reaching an elliptical orbit with the same mean altitude as that of a circular orbit require the same amount of fuel?
Would a rocket that wanted to reach an elliptical orbit with a perigee of 100 miles (160 km) and an apogee of 300 miles (480 km) burn the same amount of fuel as a rocket that wanted to attain a ...
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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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What's the motion of two connected satellites orbiting the Earth after their separation?
Let's consider the following problem (it's a job interview question): two satellites are orbiting the Earth in a circular orbit; they are rigidly linked by a tether which is always pointing in the ...
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“Parabolic”, suborbital and ballistic trajectories all follow elliptic paths. Is there a generic term for these trajectories?
There are three types of trajectories which produce microgravity but intersect with the surface of the earth:
Reduced Gravity Flights in airplanes. These are sometimes called “parabolic” but are ...
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Finding or calculating orbital velocities of celestial bodies at periapsis/apoapsis?
I'm writing a solar system simulation that uses n-body physics. To plug in the celestial bodies in our solar system, I'm copying orbital values from wikipedia. For one example, the wikipedia page for ...
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Circularization of an orbit on gmat
I'm using Gmat to turn to zero the eccentricity of an orbit around Mars with an electric thruster. I modeled the initial orbit, introduced the engine, the tank and the solar arrays and created the ...
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Calculate position of planet on fictitious orbit each day
I'm a software developer but my degree with in mathematics. I'm trying to develop a game/simulation of a fictitious randomly generated solar system, and trying to work out how to model and calculate ...
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What causes a satellite's orbit to decay?
Why do orbits of satellites orbiting at sufficient speed, far beyond the Earth's atmosphere, decay if there is no atmospheric drag? What drag is applied on the satellites at that altitude?
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What is a Mars 5-sol orbit? [closed]
I need to calculate the delta-v for descent from 5-sol orbit to the surface of Mars and then ascent back to 5-sol orbit from the surface of Mars. What is a "5-sol orbit?"
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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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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, ...
user50049
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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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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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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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