Questions tagged [orbital-maneuver]
In spaceflight, an orbital maneuver is the use of propulsion systems to change the orbit of a spacecraft.
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Why did MRO have to “both pitch upward and roll hard to the left” to point exactly at Perseverance during the entry, descent and landing phase?
The HiRise camera on the Mars Reconnaissance Orbiter snapped a beautiful photo of Perseverance falling through the Martian atmosphere hanging from its parachute.
This photo is the latest entry in this ...
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1answer
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GEO Satellite Eccentricity Maneuver
The picture above is eccentricity evolution for one year of a GEO satellite. Based on that eccentricity evolution, I want to do maneuvers to correct the eccentricity. But I have problems, I am ...
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Computing a new TLE following a delta-v impulse?
Is there some code or a library out there that can take orbital elements, add a known delta-v component and then compute a new TLE? I found this one https://apps.dtic.mil/dtic/tr/fulltext/u2/a289281....
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What if we launched rockets from space using the slingshot method and centripetal force? Would that be possible?
Would we have to build a orbiting launch station that uses centripetal force to launch the rockets? Or a station that freely floats through space not in a planets orbit? Would something like this ...
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How can firing a Space Shuttle OMS engine below 21 km cause its nozzle to “collapse”?
This answer to Can the space shuttle use OMS engines during landing? says:
No
and quotes Section 3.7 of the Orbital Maneuvering System Workbook; OMS 21002 October 10, 2006, Final version, USA006500 ...
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Why is it so hard to build crewed rockets/spacecraft able to reach escape velocity?
Why are we still not going farther than to Low Earth Orbit? Orbital velocity is about 4.8 mi/s (7.7 km/s) and escape velocity is about 7 mi/s (11.2 km/s), about 45% faster. Why is it so hard to reach ...
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200 views
Simple alternative to Powered Explicit Guidance for orbital insertion?
Say you're playing space ops engineer and want to simulate an orbital insertion---but you're petrified by the calculations needed to get the coefficients of the linear tangent law behind Powered ...
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Orbital Insertion Altitude for Rendevous with ISS
When SpaceX launches a CRS mission to the ISS, what altitude do they target at orbital insertion?
If the ISS is 400 km above ground, do they target 400 km at SECO? Or do they target a lower number---...
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1answer
99 views
How can you calculate a course based on constant acceleration burn and deceleration burn?
In the TV series The Expanse, a sci-fi space-engine called the "Epstein Fusion Drive" is a thruster capable of performing constant acceleration (up to and beyond "20g" (about $200 ...
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Falcon 9: SECO target altitude/speed?
Is there a typical target altitude and speed for SECO on a Falcon 9 CRS launch? SECO precedes orbital insertion but there are multiple orbital adjustments afterward, so I also wonder: does Dragon have ...
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Could artificial magnets orbiting the sun be used to accelerate spacecraft, like a magnetic “gravity” assist?
Say there's a powerful magnet in an orbit between those of Earth and Mars. Could a spacecraft traveling between those planets save propellant by performing a slingshot maneuver using its magnetic ...
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Using the Clohessy-Wiltshire equation, what would be the expression for ' r '?
I'm looking for an expression for r. The difficulty I'm facing is simplifying the C-W equation
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Why doesn't SpaceX know how long orbital maneuver burns will take?
While listening in on today's Crew Dragon 1 rendezvous, I noticed something interesting: the announced duration for the final coelliptic burn was "25 to 35 seconds". And this wasn't just a ...
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Changes in Orbital Parameters Due to Drag
Other than STK, are there any commercially software packages available to model changes in orbital parameters due to increases/decreases in satellite drag. I am trying to figure out if aerodynamic ...
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Analysing a phasing maneuver using GMAT- how do I reliably quantify their “phase difference”
I am trying to recreate a phasing problem that was solved on paper the previous semester, and verify my solutions using GMAT.
Two identical satellites are released on a 550km sun-synchronous orbit by ...
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General Delta V Calculation for Two-Body-Problem
Problem: Given two orbits (e.g. in the 5 keplerian elements excluding true anomaly) A and B calculate the $\Delta v$ necessary to perform a transfer from A to B using instantaneous burns.
Simple ...
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How does MEV use its “ion thruster on a stick” technology?
I was reading Politico's Biden’s space policy: One giant leap for climate change and some algorithm embedded a "Learn more about MEV; Northrop Grumman" advertisement in the story. (...
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How to determine the delta V required in order for the satellite at pt. A to hit the earth at pt. B?
I'm confused about how would I go about obtaining delta-v in this case. I'm aware of orbital transfers such as bi-elliptical but that is not the answer to this. Kindly help
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Main reasons for a 2nd burn of a 2nd stage in Earth orbit?
I have seen that sometimes the second stage of a rocket is turned on and off, then after a while turned on and off again.
What are the main reasons that second burn of a second state is initiated ...
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1answer
178 views
STK 11.2: perform a low-thrust optimal transfer
I'm using STK 11.2 to find a minimum-time finite transfer between two coplanar orbits. The first orbit is circular and has a radius 7000km, the second orbit has a <...
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1answer
269 views
Tools for low-thrust trajectory optimization
I'm performing a transfer between Near-Earth orbits considering J2 perturbation with the low-thrust engine. Orbital parameters:
...
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2answers
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Maneuver in the intersection of 2 orbits
The spacecraft transfers between two co-planar orbits. The initial orbit has the Ra = 2000km, Rp = 600km and ...
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1answer
172 views
Convert the impulsive solution to a low-thrust
The spacecraft transfers from an orbit with the following parameters:
Perigee - 700 km
Apogee - 6000 km
Inclination - 64 deg
Argument of perigee - 250 deg
to and orbit with the parameters:
Perigee -...
4
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1answer
84 views
Optimization of low-thrust in-plane maneuver
I have to build an optimal trajectory between two orbits, which are in one plane, but with different semi-major axis, argument of perigee and eccentricity.
I've read different articles regarding the ...
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Does the short-angle solution of Lambert's Method break down for very Delta-V intensive maneuvers?
Just a (hopefully) quick qualitative question that I'm having a bit of trouble extracting from the literature: I've implemented a universal-variables Lambert's method in python, and it has been ...
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1answer
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Mathematics behind attitude maneuver
I found a paper that says:
"Let's take the task of modifying the orientation of a 700kg mass spacecraft along one of it's principal axes ; a 5 deg rotation is to be performed. It is assumed that ...
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Why is it most efficient to change orbit inclination while crossing the equator?
At T+26:31 into the SpaceX ANASIS-II Mission Livestream, the host mentions that the mission trajectory calls for an orbital inclination change which is performed when the orbit of the second stage and ...
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Why will it take a couple of weeks to complete CRYOSAT 2's orbit raising of a few hundred meters?
The BBC's Esa and Nasa line up satellites to measure Antarctic sea-ice says:
Authorisation was given on Tuesday for Europe's Cryosat-2 spacecraft to raise its orbit by just under one kilometre.
This ...
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1answer
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Why are ICESAT-2 and CRYOSAT 2 both at inclinations of almost exactly 92 degrees?
The BBC's Esa and Nasa line up satellites to measure Antarctic sea-ice says:
Authorisation was given on Tuesday for Europe's Cryosat-2 spacecraft to raise its orbit by just under one kilometre.
This ...
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1answer
191 views
Get dates when a satellite has performed maneuver from historical TLE data (python)?
I have been recently acquainted with orbital mechanics and am trying to do some analysis on the subject. Since I don't have subject matter expertise, I am at a crossroads with trying to decide that ...
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2answers
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Low-thrust space tugs
For my research in the field of orbital maneuvers I consider the orbital transfers with space tugs. For the high-thrust maneuvers I used the parameters of Fregat and Volga space tugs. However, for low-...
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Orbital Rendezvous vs Hohmann Transfer
Let's assume that
a spaceship (capsule) is about to dock to the ISS
the distance between spaceship (capsule) and ISS is 20 meters
the relative velocity between the spaceship (capsule) and ISS is ...
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What happens to orbit after a radial burn?
We know from Hohmann-Transfer or bi elliptic transfer maneuvers that a burn in the tangential direction of an orbit changes the radius of the orbit.
But what happens to an object in orbit, when there ...
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How do Starlink trains spread into separate orbits with equidistant orbital slots?
Starlink satellites are launched in batches of 60. They are released from the launch vehicle, and then have to spread out – not only into equidistant slots along a single orbit ring, but now ...
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When doing an interplanetary Hohmann transfer, are additional escape and capture burns necessary in addition to the two Hohmann Transfer burns?
When doing a Hohmann transfer, it takes a burn to change from a low orbit to the Hohmann Transfer Orbit (HTO), and a second burn to change from the HTO to a high orbit. I know how to find the delta-v ...
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Why the long (19 hour) mission profile for SpaceX's trip to ISS?
As mentioned briefly in this question, The Russian Soyuz has been using a sub-4 hour path to ISS. Why the long ride from Canaveral? Or is the 19-hour timeframe typical of all launches prior to the "...
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How to calculate the wait time for Venus to Earth?
I am trying to calculate the minimum time needed for a return trip to Venus. I have calculated the time taken for the Hohmann transfers to Venus and I need to find the wait time until the return trip ...
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What exactly is a solar gravity well manouver and in what cases would it be helpful?
In this answer to the gedankenexperiment question With current state of technology if we wanted how long would it take for newly launched probe to overtake Voyagers? I've seen the term "solar gravity ...
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How much thrust is “high” thrust (for orbital transfers)
I understand that chemical rockets and nuclear thermal rockets (and possibly very high power electrical thrusters) are considered to provide "high" thrust for orbital transfers, while electrical ...
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1answer
431 views
What do the shaded vertical lines in the animation of Gravity assists of space probes, mean?
Example Animations from Wikipedia —
https://en.wikipedia.org/wiki/Gravity_assist#/media/File:Animation_of_Voyager_1_trajectory.gif
https://en.wikipedia.org/wiki/File:...
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When things land on Mars what fraction of their velocity do they remove propulsively?
Some recent comments have got me wondering about this
What is the distance between one of the mars's satellite revolving near the highest volcano olympus mons and the volcano olympus mons?
comments ...
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1answer
283 views
Station Keeping East-West Maneuver
A GEO satellite spends 14 days in longitude deadband (+/-0.067 deg). At the 14th day, I want to perform an east-west maneuver. But I am uncertain what time I should perform the maneuver at the 14th ...
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How to change RAAN with 250 m/s DV?
I'm performing a transfer between 2 orbits with different RAAN (other orbital parameters are same). The perigee altitude of the orbits is 1000km, the apogee is <...
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2answers
136 views
Lambert method for in-plane transfer
I'm trying to solve the transfer between a circular orbit with 200km radius and an orbit with 200km perigee and 8000km apogee.
The optimal transfer is hoffman, however, izzo.lambert from poliastro ...
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What engine burn/thrust could be used for satellite longitudinal change?
If you wish to change the longitude (but not the inclination) of a satellite in Low Earth Orbit, what kind of maneuvers could you use?
I am no expert, but let's say ISS or Hubble would like to stop "...
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1answer
139 views
Orbit transfer trajectory options to the moon
I am working on a project for a lunar flyby using a CubeSat. I was wondering what kind of trajectory transfer options are present and which one would be best for a CubeSat? I'm aiming for a transfer ...
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1answer
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What space simulators are the most accurate at simulating real world physics?
We've all at least heard of KSP, a popular space flight simulator. its not the best but can teach someone the basics at rocket science, delta V, burntime, basic orbital maneuvers, retrograde, prograde,...
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Aldrin cycler mission to Mars in MATLAB [closed]
I am planning to do a mission project on Aldrin Cycler (Earth to Mars) in MATLAB. Can you please suggest me where to start.
I tried reading few research paper related to this topic, any other advice?
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North-South Satellite Manuever
I am doing North-South manuever for GEO satellite. My purpose is to reduce the inclination. My initial inclination is 0.07 deg, and my target inclination is 0.0002 deg. I have tried the maneuver in ...
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Why do we prefer using the rotating reference frame rather than the Inertial frame in the three-body problem?
As the title says, I wanted to ask why do we prefer using the rotating reference frame rather than the Inertial frame in the three-body problem to place the primaries?
And how is it better for ...
